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Why are Young Women Less Likely to Breastfeed? Evidence From an Australian Population-Based Survey Mary Anne Biro, PhD, MPH, BA, RM, Jane Susanne Yelland, PhD, BAppSc, and Stephanie Janne Brown, PhD, BA (Hons) ABSTRACT: Background: Younger mothers are less likely to continue breastfeeding compared with older mothers. However, few studies have explored this finding. The aim of this study was to investigate breastfeeding initiation and duration among women aged under 25 and 25 years or older, and assess the extent to which any differences associated with maternal age were explained by other factors. Methods: All women who gave birth in September and October 2007 in two Australian states were mailed questionnaires 6 months after the birth. Women were asked about infant feeding, maternity care experiences, sociodemographic characteristics, and exposure to stressful life events and social health issues. We examined the association between maternal age, breastfeeding initiation, and breastfeeding at 6 months, while adjusting for a range of social and obstetric risk factors. Results: While younger women were just as likely to initiate breastfeeding as older women (AdjOR 1.13; 95% CI 0.63–2.05), they had almost twice the odds of not breastfeeding at 6 months (AdjOR 1.76; 95% CI 1.34– 2.33). Several psychosocial factors may explain why young women are less likely to breastfeed for longer periods. Conclusions: Given the complexity of young childbearing women’s lives, supporting them to breastfeed will require a multisectorial approach that addresses social disadvantage and resulting health inequalities. (BIRTH 41:3 September 2014)
Key words: breastfeeding, social disadvantage, young women
Introduction Recent Australian data indicate that breastfeeding is initiated for 96.0 percent of infants aged 0–2 years, and by 6 months of age around 60 percent are still receiving breastmilk (1). While these rates have increased compared with the last national survey (2), marked discrepancies in breastfeeding duration continue to exist among specific groups of mothers. Younger mothers, women who smoke in pregnancy, women who are less Mary Anne Biro, PhD, MPH, BA, RM, is a Senior Lecturer at the School of Nursing & Midwifery, Monash University, Clayton, Vic., Australia, and Honorary Senior Research Fellow, Healthy Mothers Healthy Families Group at Murdoch Childrens Research Institute, Melbourne, Vic., Australia; Jane Susanne Yelland, PhD, BAppSc, is a Senior Research Fellow at Murdoch Childrens Research Institute, Parkville, Vic., Australia; Stephanie Janne Brown, PhD, BA (Hons), is a Principal Research Fellow and Group Leader, Healthy Mothers Healthy Families Group at Murdoch Childrens Research Institute, Parkville, Victoria, Australia, and Honorary Principal Research Fellow, General Practice & Primary Health Care Academic Centre and
educated, and women of lower socioeconomic status are less likely to be breastfeeding at 6 months (1). The age profile of women giving birth in Australia has changed in the previous decade. The average age of mothers has increased from 29.2 years in 2001 to 30 years in 2010 with the proportion of women giving birth aged 35 years increasing from 17.5 percent to 23.0 percent. In contrast, the proportion of mothers aged 20–24 years declined from 15.5 percent to 14.2 percent and the proportion of teenage mothers (younger School of Population Health, University of Melbourne, Parkville, Vic., Australia. Address correspondence to Dr. Mary Anne Biro, Senior Lecturer, School of Nursing & Midwifery, Monash University, Vic. 3800, Australia. Accepted February 13, 2014 © 2014 Wiley Periodicals, Inc.
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246 than 20 years) also declined from 5.0 percent to 3.9 percent (3) during this same time period. The typical age at which women now give birth is between 25 and 34 years (3). In a study examining socioeconomic status and rates of breastfeeding in Australia, Amir and Donath (4) found that mothers living in the most deprived neighborhoods were less likely to be breastfeeding at 6 months compared with mothers living in more advantaged areas. In a review of the literature on the factors associated with breastfeeding at 6 months, Forster, McLachlan and Lumley (5) found that lower income, returning to work, perception of lack of breastfeeding support, lower infant birthweight, cesarean section, and admission to special care nursery were negatively associated with breastfeeding duration. Factors positively associated with breastfeeding at 6 months included higher maternal education, not smoking, being married, or not being single. A consistent finding is that younger maternal age is associated with shorter duration of breastfeeding (5). Although this observation is frequently reported, few studies have explored what lies beneath this finding, in particular, the extent to which the association between breastfeeding and maternal age is explained by the greater likelihood of younger mothers experiencing significant social disadvantage. This paper draws on data collected in an Australian population-based survey of women giving birth in South Australia and Victoria to: (1) investigate initiation and duration of breastfeeding among women aged under 25 years and women aged 25 years or older, and (2) assess the extent to which differences in patterns of initiation and duration of breastfeeding associated with maternal age are explained by other social and obstetric risk factors, including exposure to stressful life events and social health issues during and after pregnancy. We hypothesized that women exposed to a greater number of stressful life events and social health issues would be less likely to initiate breastfeeding or to continue breastfeeding at 6 months postpartum, and that the greater likelihood of younger women experiencing multiple social health issues would partially explain the association between maternal age and breastfeeding initiation and duration.
Methods Sample Questionnaires together with an invitation to participate were mailed to all women who gave birth in Victoria and South Australia in September/October 2007, excluding those who had a stillbirth, or whose
baby was known to have died. Births in Victoria and South Australia accounted for 31.3 percent of all births in Australia in 2007. All public and private hospitals with births in the study period (n = 110) and home birth practitioners in both states agreed to participate by mailing questionnaires to women at five to 6 months postpartum. One small hospital later withdrew. The invitation package included an explanation of the study in six community languages (Arabic, Vietnamese, Cantonese, Mandarin, Somali, and Turkish). Two reminders were sent at 2-week intervals; the second of these included a repeat copy of the questionnaire. Research ethics approval was obtained from the ethics committee of the Victorian Department of Human Services, the South Australian Department of Health, the University of South Australia, the Royal Children’s Hospital, and 10 hospitals.
Questionnaire The questionnaire was designed to explore women’s views and experiences of care during pregnancy, labor, birth, and the first 6 months after birth, and included detailed questions about women’s experiences of postnatal care, maternal sociodemographic characteristics, exposure to stressful life events and social health issues, and maternal and infant health outcomes. Initiation and duration of breastfeeding was assessed based on responses to a series of questions which asked: “While you were in hospital, did you ever breastfeed or give your baby expressed breastmilk?”; “During your first week at home did you breastfeed your baby (please include expressed breastmilk)?”; “Are you continuing to breastfeed your baby (or giving expressed breastmilk)?” and “If you started to breastfeed, and have stopped, how old was your baby when you stopped?” It was not possible to determine if women were exclusively breastfeeding beyond the first week at home after the birth. Babies having some formula feeds and some breastmilk feeds were categorized as breastfed for the purposes of analysis. Measures of socioeconomic status included maternal relationship status, educational attainment (completion of secondary school), total family income before tax, possession of a current health care concession card (an indicator of financial hardship), and health insurance status (private cover/Medicare only). Maternal prepregnant body mass index (BMI) was calculated as the ratio of body weight in kilograms divided by the square of height in meters. Smoking during pregnancy was assessed using a multiple response question to
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determine if women had never smoked, quit before their pregnancy, quit when they found out they were pregnant, or continued to smoke during pregnancy (6). Women who said they had quit before pregnancy or who had never smoked were categorized as not smoking. The questionnaire also included a 23-item inventory for assessing stressful life events and social health issues in the 12 months before the birth, and during the first 6 months postpartum. This inventory drew on items from the Pregnancy Risk Assessment and Monitoring Study (PRAMS) (7), a review of relevant literature, community consultations with Aboriginal organizations and communities in both states, and feedback from women participating in the pilot phase of the study. The 23-item inventory included major life events such as separation and divorce, death of a family member or close friend, moving house, and social health issues such as serious family conflict, having a lot of bills you could not pay, not having enough money to buy food, and legal problems. Further details about this measure are published elsewhere (8). Information was also collected on mode of birth, infant birthweight, length of postnatal hospital stay, infant admissions to neonatal or special care nursery, and whether or not the hospital where women gave birth was accredited with the Baby Friendly Hospital Initiative (BFHI). A measure of women’s overall satisfaction with postnatal care in hospital was obtained by asking: “Overall, how would describe the care you and your baby received in hospital after the birth?” with the following five response options: “very good,” “good,” “mixed,” “poor,” or “very poor.”
Statistical Analysis Data on breastfeeding were analyzed to identify the proportions of women who (1) initiated breastfeeding, (2) continued to breastfeed at 6 weeks postpartum, and (3) continued to breastfeed at 6 months postpartum comparing younger and older women (< 25 years/ ≥ 25 years). Maternal sociodemographic and other factors associated with breastfeeding initiation and duration were analyzed using logistic regression. Covariates were specified a priori and included those that have been found to be significantly associated with the main exposure of interest (age) and the primary outcome (any breastfeeding). Multivariable logistic regression was used to examine the association between maternal age, breastfeeding initiation and breastfeeding at 6 months postpartum adjusting for maternal smoking, measures of socioeconomic status, exposure to social adversity, parity, mode of birth, postnatal length of stay in hospital, and other organizational factors. Compari-
sons are presented using odds ratios and 95 percent confidence intervals. Data were analyzed using STATA version 11.0 (9).
Results Participating hospitals and home birth practitioners identified 8,597 eligible women giving birth in the study period. Excluding questionnaires returned to sender, duplicate responses, and women inadvertently mailed questionnaires who gave birth outside the study period, we conservatively estimate that the response fraction was 51.6 percent (4,366/8,468). However, it is likely to have been higher as several hospitals had problems completing mailouts.
Characteristics of the Sample Women taking part in the survey were largely representative in terms of parity, method of birth, and infant birthweight compared with records for births in the study period collected by the Perinatal Data Collection Unit in Victoria (10) and the Pregnancy Outcome Unit in South Australia (11). However, the following groups were underrepresented when compared with all women who gave birth in Victoria and South Australia during the study period. Younger women (under 25 years) comprised 9.5 percent (416/4,366) of the sample, compared with 16.0 percent of all women giving birth in the study period. In addition, single women (3.3% vs 11.3%), women born overseas of non-English speaking background (12.2% vs 18.1%), and Aboriginal and Torres Strait Islander women were underrepresented (0.8% vs 1.3%). The mean age of women in the sample was 31.7 years (range: 16.0– 46.3 years). The sociodemographic, obstetric, and other characteristics of younger and older women in the sample are shown in Table 1. Compared with older women, younger women were more likely to be unmarried, not to have completed secondary school, have a health care concession card, and not have private health insurance indicating relative social disadvantage. They were also more likely to smoke in pregnancy and to report three or more stressful life events and social issues in the 12 months before their baby was born, and in the first 6 months after the birth. Fewer young women had a cesarean section (23.5 vs 33.7% of older women) and more younger women left hospital within 48 hours of giving birth (31.9 vs 21.5% of older women). Younger women were more likely to have given birth in a BFHI accredited hospital. No differences existed in the proportion of infants admitted to neonatal intensive care/
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248 Table 1. Sociodemographic, Obstetric, and Other Characteristics of Younger and Older Women (n = 4,366)
Characteristic
< 25 years
Relationship status Married 175 Living with partner 184 Divorced/separated/ 49 widowed/single Maternal country of birth Australia 340 Overseas-English 14 speaking Overseas-Non52 English speaking Maternal education Completed secondary 228 school Did not complete 180 secondary school Health care concession card Yes 224 No 184 Private health insurance Yes 46 No 360 Household Income (AUD) < $30,000 pa 88 $30,000–$50,000 pa 120 $51,000–$70,000 pa 86 > $70,000 pa 46 Smoking in pregnancy Did not smoke in 261 pregnancy Quit in pregnancy 54 Smoked in pregnancy 92 Parity Primiparous 286 Multiparous 124 BMI before pregnancy < 20 76 20–25 159 > 25 to < 30 80 ≥ 30 55 Method of birth Spontaneous vaginal 256 Operative vaginal 56 Cesarean section (not 30 in labor) Cesarean section (in 66 labor)
≥ 25 years
p*
(42.9) (45.1) (12.0)
3,009 (80.3) < 0.001 630 (16.8) 107 (2.9)
(83.7) (3.5)
3,084 (81.7) < 0.05 248 (6.7)
(12.8)
(55.9) (44.1)
435 (11.7)
3,056 (81.9) < 0.001 676 (18.1)
(54.9) (45.1)
665 (17.8) < 0.001 3,074 (82.2)
(11.3) (88.7)
1,971 (52.7) < 0.001 1,769 (47.3)
(25.9) (35.3) (25.3) (13.5)
254 482 735 1,933
(64.1)
3,100 (84.5) < 0.001
(13.3) (22.6)
(7.5) < 0.001 (14.2) (21.6) (56.8)
278 (7.6) 290 (7.9)
(69.8) (30.2)
1,552 (41.4) < 0.001 2,200 (58.6)
(20.5) (43.0) (21.6) (14.9)
489 1,746 783 509
(62.8) (13.7) (7.4)
1,964 (52.4) < 0.001 518 (13.8) 735 (19.6)
(16.2)
(13.9) < 0.01 (49.5) (22.2) (14.4)
529 (14.1)
(continued)
Table 1. Continued
Characteristic
< 25 years
≥ 25 years
Infant birthweight (grams) < 2,500 17 (4.4) 148 (4.1) 2,500–2,999 59 (15.2) 454 (12.7) 3,000–3,499 140 (36.1) 1,294 (36.2) 3,500–3,999 114 (29.4) 1,219 (34.1) > 4,000 58 (15.0) 464 (13.0) Baby admitted to SCN Yes 80 (19.6) 637 (17.0) No 328 (80.4) 3,103 (83.0) Length of stay in hospital ≤ 24 hr 43 (10.7) 251 (6.8) 25–48 hr 85 (21.2) 542 (14.7) 3 days 101 (25.2) 612 (20.5) 4 days 60 (15.0) 758 (20.5) 5 days 75 (18.70) 1,012 (27.4) 6 days 37 (6.6) 525 (14.2) Gave birth in BFHI hospital Yes 154 (37.8) 817 (21.9) No 254 (62.3) 2,915 (78.1) Stressful life events/social issues in pregnancy None 84 (20.6) 1,309 (35.0) 1–2 issues 165 (40.4) 1,873 (50.0) 3 issues 159 (39.0) 563 (15.0) Stressful life events/social issues in postnatal period None 139 (33.9) 2,047 (54.6) 1–2 issues 176 (42.9) 1,396 (37.2) 3 issues 95 (23.2) 306 (8.2)
p* 0.28
0.19
< 0.001
< 0.001
< 0.001
< 0.001
Denominators vary because of missing values. *Chi-square tests for statistical significance. BMI = Body Mass Index; BFHI = Baby Friendly Hospital Initiative; SCN = special care nursery.
special care nursery or with a low birthweight (< 2,500 grams) comparing younger and older women.
Breastfeeding We analyzed the number of women who initiated and were breastfeeding at 1 week, 6 weeks, and 6 months to examine the rates for younger women compared with older women over these time periods. The denominators used to derive these proportions were the total number of younger and older women in the sample for whom we had both age and infant feeding data. Figure 1 shows the proportions of younger and older women in the total sample who were breastfeeding (any) at each time point. The figure illustrates a widening gap in breastfeeding discontinuation between younger and older women from 1 week after the birth.
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Younger Women and Breastfeeding Complete data are available for breastfeeding initiation for 3,514 participants, and for breastfeeding at 6 months for 3,245 participants. These women did not differ in terms of their sociodemographic characteristics when compared with those who were excluded because of incomplete data. In addition to maternal age as the exposure of main interest, 13 variables, specified a priori, were fitted in a multivariable logistic regression model with breastfeeding initiation as the outcome variable (Table 2). On examining the association between age and breastfeeding initiation, we found that younger women were just as likely to initiate breastfeeding as older women, while adjusting for social and obstetric risk factors, including exposure to stressful life events and social health issues during and after pregnancy (Table 2).
Young Women and Breastfeeding Continuation The same 13 variables with the addition of satisfaction with postnatal care were fitted in a multivariable logistic regression model with maternal age as the exposure 100 90 80 70 60 % 50 40 30 20 10 0
< 25 years ≥ 25 years
In hospital (n = 4154)
1st week (n=4146)
Six weeks (n=3805)
Six months (n=3805)
Fig. 1. Any breastfeeding for young (< 25 years) versus older women (≥ 25 years).
Table 2. Association Between Age and Breastfeeding Initiation (n = 3,514)
Age < 25 years ≥ 25 years (ref)
Initiated BFa
Did not initiate BF
Adjusted OR* (95% CI)
312 (94.8) 3,032 (95.2)
17 (5.2) 153 (4.8)
1.13 (0.63–2.05) 1.00
*Adjusted for relationship status, maternal education, health concession card, private insurance, smoking status, parity, body mass index, method of birth, infant birthweight, admission to special care nursery, length of stay, Baby Friendly Hospital Initiative status of hospital, stressful life events/social issues in pregnancy. aBF = breastfeeding.
of main interest and breastfeeding at 6 months as the outcome variable (Table 3). Younger women had significantly raised odds of not breastfeeding at 6 months postpartum, which were only moderately attenuated by taking other sociodemographic, obstetric, and organizational factors into account (Table 3). After adjusting for other variables in the model, women had raised odds of not breastfeeding at 6 months if they: were aged 25 years or younger; quit smoking or continued to smoke in pregnancy; did not complete secondary school; had a BMI greater than 25 (overweight or obese); gave birth operatively; or rated their hospital postnatal care as less than “very good.”
Discussion Improving breastfeeding duration and exclusivity are global health priorities. Despite Australian government and WHO recommendations for exclusive breastfeeding up to 6 months (12,13), there are marked inequalities in breastfeeding duration. Our findings show that young women were less likely to be breastfeeding at 1 week, 6 weeks, and 6 months postpartum. While young women were just as likely to initiate breastfeeding compared with their older counterparts, a decline in breastfeeding was seen in this group as early as the first week after birth. By 6 months, young women were almost twice as likely to have stopped breastfeeding compared with the older age cohort. The study reveals several factors that may explain why young women are less likely to breastfeed for longer periods. Young women were more likely to be single, on a health care concession card, not to have completed secondary schooling, more likely to smoke, and more likely to be having their first baby. In addition, the regression analysis revealed that not completing secondary schooling and smoking in pregnancy were significantly associated with the discontinuation of breastfeeding at 6 months. Although younger women were significantly more likely to experience multiple stressful life events and social health issues in pregnancy and the postpartum period compared with their older counterparts, there was no association between stressful life events and social health issues in pregnancy and breastfeeding cessation. Yelland et al suggest that pregnant women experiencing complex life events are at a double disadvantage in that they are more likely to receive care that is not matched to their needs. This analogy of double disadvantage could be applied equally to younger women’s experience of advice and support with regard to breastfeeding. These authors recommend the development of tailored approaches to perinatal care that specifically address the needs of vulnerable women. Young women
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250 Table 3. Factors Associated with Not Breastfeeding at 6 Months (n = 3,245)
Age < 25 years ≥ 25 years (ref) Relationship status Married (ref) Partner/defacto Not partnered Maternal education Completed Year 12 (ref) Did not complete year 12 Health care concession card No (ref) Yes Private health insurance Yes (ref) No Smoking in pregnancy No (ref) Quit in pregnancy Smoked in pregnancy Parity Primiparous (ref) Multiparous BMI before pregnancy < 20 20–25 (ref) > 25 to < 30 ≥ 30 Method of birth Spontaneous vaginal (ref) Operative vaginal Cesarean (not in labor) Cesarean (in labor) Infant birthweight (grams) < 2,500 2,500–2,999 3,000–3,499 (ref) 3,500–3,999 4,000+ Baby admitted to SCN No (ref) Yes Length of stay in hospital < 24 hr 2 days
Breastfeeding (n = 2,036)
Not breastfeeding (n = 1,209)
125 (43.0) 1,911 (64.7)
166 (57.0) 1,043 (35.3)
1.76 (1.34–2.33) 1.00
1,656 (65.2) 335 (54.8) 45 (48.4)
885 (34.8) 276 (45.2) 48 (51.6)
1.00 1.06 (0.87–1.30) 1.11 (0.69–1.78)
1,741 (65.9) 295 (49.0)
902 (34.1) 307 (51.0)
1.00 1.54 (1.27–1.88)
1,699 (64.7) 337 (54.5)
928 (35.3) 281 (45.5)
1.00 1.02 (0.83 to 1.26)
1,105 (67.0) 931 (58.3)
544 (33.0) 665 (41.7)
1.00 1.08 (0.90–1.30)
1,805 (65.9) 125 (50.6) 106 (40.9)
934 (34.1) 122 (49.4) 153 (59.1)
1.00 1.59 (1.20–2.09) 1.97 (1.48–2.62)
867 (60.0) 1,169 (65.0)
579 (40.0) 630 (35.0)
1.00 0.90 (0.76–1.07)
308 1,088 414 226
(65.3) (68.0) (57.0) (50.5)
164 511 312 222
(34.8) (32.0) (43.0) (49.6)
1.06 (0.84–1.32) 1.00 1.55 (1.28–1.87) 1.87 (1.50–2.34)
1,171 256 338 271
(66.6) (56.9) (59.0) (58.5)
588 194 235 192
(33.4) (43.1) (41.0) (41.5)
1.00 1.51 (1.20–1.91) 1.40 (1.12–1.76) 1.26 (0.98–1.61)
67 250 733 705 281
(51.9) (59.7) (62.3) (65.3) (63.9)
62 169 444 375 159
(48.1) (40.3) (37.7) (34.7) (36.1)
1.25 1.06 1.00 0.89 0.83
Adjusted OR (95% CI)
(0.83–1.88) (0.83–1.34) (0.74–1.06) (0.65–1.06)
1,720 (64.0) 316 (56.5)
966 (36.0) 243 (43.5)
1.00 1.11 (0.90–1.37)
142 (64.8) 303 (60.0)
77 (35.2) 202 (40.0)
0.98 (0.69–1.38) 1.17 (0.90–1.52) (continued)
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Table 3. Continued
Breastfeeding (n = 2,036) 3 days (ref) 346 (63.4) 4 days 421 (64.8) 5 days 567 (64.2) 6+ days 257 (58.1) Gave birth in BFHI hospital Yes 420 (56.2) No (ref) 1,616 (64.7) Stressful life events/social issues in the postnatal period None (ref) 1,139 (66.0) 1–2 736 (60.2) 3 or more 161 (54.6) Overall rating of hospital postnatal care “Very good” (ref) 1,266 (65.3) Less than “very good” 673 (34.7)
Not breastfeeding (n = 1,209) 200 229 316 185
Adjusted OR (95% CI)
(36.6) (35.2) (35.8) (41.9)
1.00 1.06 (0.82–1.37) 1.05 (0.82–1.36) 1.17 (0.86–1.59)
327 (43.8) 882 (35.3)
0.84 (0.70–1.01) 1.00
588 (34.1) 487 (39.8) 134 (45.4)
1.00 1.12 (0.96–1.32) 1.08 (0.82–1.42)
770 (60.0) 536 (41.0)
1.00 1.19 (1.02–1.39)
BMI = Body Mass Index; BFHI = Baby Friendly Hospital Initiative; SCN = special care nursery.
experiencing multiple stressful life events and social health issues are one such group who may benefit from individualized breastfeeding advice and support (14). In a systematic review examining the nature of effective breastfeeding support for adolescents, Hall Moran and colleagues (15) found evidence that specific and targeted education programs for adolescents may improve breastfeeding initiation and continuation rates. In addition, Hall Moran et al identified five types of support, and of these, adolescents found emotional, network, and esteem support the most helpful. Biro suggests that midwives may be well-placed to help establish breastfeeding support programs, which have shown some promise in areas where breastfeeding initiation and duration are not high (16,17). Others have suggested working with groups (including younger women) at greater risk of breastfeeding cessation and testing interventions that have been shown to be successful elsewhere (5). In a paper on the inequalities and inequities in breastfeeding, Cattaneo challenges health professionals that they are failing in their responsibilities if they do not act to remove the barriers for all mothers in accessing good quality breastfeeding support (18). Cattaneo also suggests breastfeeding inequities will only be reduced if strategies to support women to breastfeed actively target women from socially disadvantaged backgrounds more so than the general population, that is, care and support should be proportionate to need (18). He reports on several systematic reviews of interventions which have been shown to be effective at increasing breastfeeding rates, including professional and peer support and what constitutes effective support from the mother’s perspective. Similarly, Amir and
Donath (4) suggest that breastfeeding support and promotion should focus on groups with low rates of breastfeeding. Meedya, Fahy and Kable (19) also recommend that midwives focus their education and support on young mothers and those from low socioeconomic backgrounds. Viner et al suggest that improving adolescent health generally requires structural changes to improve education and employment together with supportive families, peers, and school environments (20). Amir and Donath in their critique of breastfeeding and socioeconomic factors also suggest a policy approach to acting on increasing health inequalities (4). Although health care professionals have a significant role to play, they cannot reduce breastfeeding inequalities alone. As Viner et al point out, youth health and wellbeing should be policy priorities across all government sectors (20). In a report to the National Youth Affairs Research Scheme, Loxton and colleagues propose several evidence-based strategies to address service delivery barriers for young pregnant women and mothers (21). They recommend among other things locating care in local communities, developing accessible “one-stop” shops or hubs with a variety of services, and follow-up care incorporating home visits, telephone calls, and SMS communication technology. In addition, they recommend addressing young women’s health literacy needs, the establishment of formal peer support programs and specialized in-school programs, and the development and implementation of a set of best practice principles for working with young pregnant women and mothers. The survey provided an opportunity to examine aspects of the organization of postnatal care and care
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252 provision. Young women were more likely to leave hospital within 48 hours of birth when compared with women aged 25 years or older. However, a shorter postnatal hospital stay was not associated with breastfeeding cessation, supporting the findings of three previous Victorian population-based surveys of recent mothers (22), and a systematic review of randomized trials evaluating early postnatal discharge for healthy mothers of term infants (23). Younger women were also far more likely to give birth in a BFHI hospital yet no association existed between birth hospital accreditation and duration of breastfeeding. In a recent Australian population-based study, Brodribb et al found that evidence-based supportive breastfeeding practices rather than BFHI accreditation per se positively influenced breastfeeding rates at one and 4 months (24). How women experienced the care they received in hospital after birth was associated with breastfeeding duration, with those rating their care as less than “very good” more likely to have stopped breastfeeding by 6 months.
collection (30). Potential misclassification of infant feeding at particular time points cannot be overlooked. However, while Li, Scanlon and Serdula (31) found that validity and reliability of maternal recall for the age at introduction of food and fluids other than breastmilk was less accurate, women’s recall for breastfeeding initiation and duration has been found to be accurate (31). Although we acknowledge that much of the literature we have referred to focuses on adolescent mothers and interventions that may increase breastfeeding duration in this group, our study suggests that similar factors are operating in the group of mothers we defined as young (i.e., < 25 years). In the context of the increasing age profile of childbearing women, it is important to recognize that even women giving birth in their early twenties may have different ideas, beliefs, and behaviors compared with their older counterparts, and may need additional support tailored to their particular circumstances to achieve rates of breastfeeding comparable to older women.
Strengths and Limitations
Conclusions
Although the response fraction of 51.6 percent was less than that in previous population-based surveys of recent mothers in Victoria (25–27), participants were representative in terms of important obstetric characteristics such as parity, method of birth, and infant birthweight. However, young women, single women, Aboriginal and Torres Strait Islander women, and those from a nonEnglish-speaking background were underrepresented. Prevalence estimates for breastfeeding initiation and duration must be considered in the light of the underrepresentation of these groups, and especially the underrepresentation of young women. It is possible that the young women who did respond to the survey differ from those who did not and therefore possible that the prevalence of breastfeeding was overestimated for young women specifically. Based on the results of the Australian National Infant Feeding survey (1), the proportion of women giving any breastmilk to their infants at 6 months was 39.1 percent. In our study, the proportion of young women reporting that they were giving any breastmilk at 6 months was 43.0 percent. Although the response fraction was lower than anticipated, this is unlikely to have had a marked effect on estimates of association. Two recent studies provide robust evidence to support the assumption that estimates of association between variables remain reliable in studies with much lower response fractions than in the current study (28,29). To address some of the methodological limitations of surveying women about infant feeding practices, Tomeo and colleagues have advocated for prospective data
Although young women in Australia are as likely to initiate breastfeeding compared with their older counterparts, they are more likely to cease breastfeeding earlier with the decline occurring as early as 1 week postpartum. Although health care professionals have a significant role to play, they cannot reduce breastfeeding inequalities alone. Given the complexity of young childbearing women’s lives, supporting younger women to breastfeed will require a multisectorial approach that addresses social disadvantage and resulting health inequalities.
Funding We acknowledge the funding provided by the National Health and Medical Research Council (ID: 433012), the Victorian Department of Human Services, the South Australian Department of Health, and the Victorian Government’s Operational Infrastructure Support Program. SB was supported by a National Health and Medical Research Council Career Development Fellowship (ID: 491205, 2008–2011) and currently holds an Australian Research Council Future Fellowship.
Acknowledgments We are most grateful to the thousands of women who participated in the survey at a particularly busy time of their lives, and to the hospitals in South Australia and
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Victoria who helped in mailing out questionnaires. We are grateful to the following large team of study investigators who have contributed to the development of the research protocol and conduct of the study: Peter Baghurst, Jane Gunn, Jeffrey Robinson, Georgie Stamp, Euan Wallace; and acknowledge with gratitude the significant contribution of the following staff in the conduct of the study: Georgina Sutherland, Katherine Chisholm, Maggie Flood, Monique Keel, Jenny Kelly, Penny Marlowe, Renee Paxton, and Jan Wiebe. We thank the other members of the Healthy Mothers Healthy Families Research group for their ongoing support of the study.
14.
15.
16.
17.
18.
References 1. Australian Institute of Health and Welfare. 2010 Australian National Infant Feeding Survey: Indicator results 2011. Canberra, Australia: AIHW. Accessed August 1, 2013. Available at: http:// www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=10737420925. 2. Australian Bureau of Statistics. National Health Survey; users’ guide, 2004–2005. Canberra, Australia: ABS, 2006. (ABS Cat. No. 4363.055.001). 3. Li Z, Zeki R, Hilder L, Sullivan EA 2012. Australia’s mothers and babies 2010. Perinatal statistics series no. 27. Cat. no. PER 57. Canberra, Australia: AIHW National Perinatal Epidemiology and Statistics Unit. 4. Amir L, Donath S. Socioeconomic status and rates of breastfeeding in Australia: Evidence from three recent national health surveys. Med J Aust 2008;189(5):254–256. 5. Forster DA, McLachlan HL, Lumley J. Factors associated with breastfeeding at six months postpartum in a group of Australian women. Int Breastfeed J 2006; 1(18). DOI:10.1186/1746-43581-18. 6. Perlen S, Brown S, Yelland J. Have guidelines about smoking cessation support in pregnancy changed practice in Victoria, Australia? Birth 2013;40(2):81–87. 7. Colley Gilbert BJ, Shulman HB, Fischer LA, Rogers MM. The Pregnancy Risk Assessment Monitoring System (PRAMS): Methods and 1996 response rates from 11 states. Matern Child Health J 1999, 3:199–209. 8. Brown SJ, Yelland JS, Sutherland GA, et al. Stressful life events, social health issues and low birthweight in an Australian population-based birth cohort: challenges and opportunities in antenatal care. BMC Public Health 2011;11:196. 9. StataCorp. Stata Statistical Software: Release 11. College Station, Texas: StataCorp LP; 2007. 10. Consultative Council on Obstetric and Paediatric Mortality and Morbidity. Births in Victoria 2007 and 2008. Melbourne, Australia: Department of Health; 2011. 11. Chan A, Scott J, Nguyen A-M, Sage L. Pregnancy Outcome in South Australia 2007. Adelaide, Australia: Pregnancy Outcome Unit, SA Health, Government of South Australia, 2008. 12. World Health Organization. Breastfeeding-exclusive breastfeeding. e-Library of Evidence for Nutrition Actions (eLENA). 2013. Accessed August 1, 2013. Available at: http://www.who.int/elena/ titles/exclusive_breastfeeding/en/index.html. 13. National Health and Medical Research Council. Australian Dietary Guidelines. 2013, Canberra, Australia: National Health and
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Medical Research Council. Accessed August 1, 2013. Available at: http://www.nhmrc.gov.au/guidelines/publications/n55. Yelland JS, Sutherland GA, Brown SJ. Women’s experience of discrimination in Australian Perinatal Care: The double disadvantage of social adversity and unequal care. Birth 2012;39(3):211– 220. Hall MV, Edwards J, Dykes F, Downe S. A systematic review of the nature of support for breast-feeding adolescent mothers. Midwifery 2007; 23(2):157–171. Biro M. What has public health got to do with midwifery? Midwives role in securing better health outcomes for mothers and babies. Women & Birth 2011;24(1):17–23. Britton C, McCormick FM, Renfrew MJ, et al. Support for breastfeeding mothers. Cochrane Database of Syst Rev 2007. Issue No.: 1; Art. No.: CD001141. DOI: 10.1002/14651858. CD001141.pub3. Cattaneo A. Academy of Breastfeeding Medicine Founder’s Lecture 2011: Inequalities and Inequities in Breastfeeding: an International Perspective. Breastfeed Med 2012;7(1):3–9. doi:10.1089/ bfm. 2012.9999. Meedya S, Fahy K, Kable A. Factors that positively influence breastfeeding duration to 6 months: A literature review. Women & Birth 2010;23:135–145. Viner RM, Ozer EM, Denny S, et al. Adolescence and the social determinants of health. Lancet 2012;379:1641–1652. Loxton D, Stewart WJ, Adamson L. Barriers to service delivery for young pregnant women and mothers. Report to the National Youth Affairs Research Scheme (NYARS). 2007. Canberra, Australia: Australian Government Department of Families, Community Services and Indigenous Affairs (FaCSIA) on behalf of NYARS. Accessed September 2, 2013. Available at: http://trove. nla.gov.au/work/34656581?selectedversion=NBD42333210. Brown S, Bruinsma F, Darcy M-A, et al. Early discharge: No evidence of adverse outcomes in three consecutive populationbased Australian surveys of recent mothers, conducted in 1989, 1994 and 2000. Paediatr Perinat Epidemiol 2004;18(3):202–213. Brown S, Small R, Argus B, et al. Early postnatal discharge from hospital for healthy mothers and term infants. Cochrane Database of Syst Rev 2002; Issue no.: 3; Art. No.: CD002958. DOI: 10.1002/14651858.CD002958. Brodribb W, Kruske S, Miller YD. Baby-Friendly Hospital Accreditation. In-hospital care practices and Breastfeeding. Pediatrics 2013;131(4):685–692. Brown S, Lumley J. Satisfaction with labor and birth: A survey of 790 Australian women. Birth 1994;21:4–13. Brown S, Lumley J. Changing childbirth: Lessons from an Australian survey of 1336 women. BJOG 1998;105:143–155. Brown SJ, Davey MA, Bruinsma FJ. Women’s views and experiences of postnatal hospital care in the Victorian Survey of Recent Mothers 2000. Midwifery 2005;21:109–129. Martikainen P, Laaksonen M, Piha K, Lalluka T. Does survey non-response bias the association between occupational socialclass and health? Scand J Public Health 2007;35(2):212–215. Mealing NM, Banks E, Jorm LR, et al. Investigation of relative risk estimates from studies of the same population with contrasting response rates and designs. BMC Med Res Methodol 2010;10:26. Tomeo CA, Rich-Edwards JW, Michels KB, et al. Reproducibility and validity of maternal recall of pregnancy-related events. Epidemiology 1999;10:774–777. Li R, Scanlon KS, Serdula MK. The validity and reliability of maternal recall of breastfeeding practice. Nutr Rev 2005;63(4): 103–110.
BIRTH 41:3 September 2014
Why are Young Women Less Likely to Breastfeed? Evidence From an Australian Population-Based Survey Mary Anne Biro, PhD, MPH, BA, RM, Jane Susanne Yelland, PhD, BAppSc, and Stephanie Janne Brown, PhD, BA (Hons) ABSTRACT: Background: Younger mothers are less likely to continue breastfeeding compared with older mothers. However, few studies have explored this finding. The aim of this study was to investigate breastfeeding initiation and duration among women aged under 25 and 25 years or older, and assess the extent to which any differences associated with maternal age were explained by other factors. Methods: All women who gave birth in September and October 2007 in two Australian states were mailed questionnaires 6 months after the birth. Women were asked about infant feeding, maternity care experiences, sociodemographic characteristics, and exposure to stressful life events and social health issues. We examined the association between maternal age, breastfeeding initiation, and breastfeeding at 6 months, while adjusting for a range of social and obstetric risk factors. Results: While younger women were just as likely to initiate breastfeeding as older women (AdjOR 1.13; 95% CI 0.63–2.05), they had almost twice the odds of not breastfeeding at 6 months (AdjOR 1.76; 95% CI 1.34– 2.33). Several psychosocial factors may explain why young women are less likely to breastfeed for longer periods. Conclusions: Given the complexity of young childbearing women’s lives, supporting them to breastfeed will require a multisectorial approach that addresses social disadvantage and resulting health inequalities. (BIRTH 41:3 September 2014)
Key words: breastfeeding, social disadvantage, young women
Introduction Recent Australian data indicate that breastfeeding is initiated for 96.0 percent of infants aged 0–2 years, and by 6 months of age around 60 percent are still receiving breastmilk (1). While these rates have increased compared with the last national survey (2), marked discrepancies in breastfeeding duration continue to exist among specific groups of mothers. Younger mothers, women who smoke in pregnancy, women who are less Mary Anne Biro, PhD, MPH, BA, RM, is a Senior Lecturer at the School of Nursing & Midwifery, Monash University, Clayton, Vic., Australia, and Honorary Senior Research Fellow, Healthy Mothers Healthy Families Group at Murdoch Childrens Research Institute, Melbourne, Vic., Australia; Jane Susanne Yelland, PhD, BAppSc, is a Senior Research Fellow at Murdoch Childrens Research Institute, Parkville, Vic., Australia; Stephanie Janne Brown, PhD, BA (Hons), is a Principal Research Fellow and Group Leader, Healthy Mothers Healthy Families Group at Murdoch Childrens Research Institute, Parkville, Victoria, Australia, and Honorary Principal Research Fellow, General Practice & Primary Health Care Academic Centre and
educated, and women of lower socioeconomic status are less likely to be breastfeeding at 6 months (1). The age profile of women giving birth in Australia has changed in the previous decade. The average age of mothers has increased from 29.2 years in 2001 to 30 years in 2010 with the proportion of women giving birth aged 35 years increasing from 17.5 percent to 23.0 percent. In contrast, the proportion of mothers aged 20–24 years declined from 15.5 percent to 14.2 percent and the proportion of teenage mothers (younger School of Population Health, University of Melbourne, Parkville, Vic., Australia. Address correspondence to Dr. Mary Anne Biro, Senior Lecturer, School of Nursing & Midwifery, Monash University, Vic. 3800, Australia. Accepted February 13, 2014 © 2014 Wiley Periodicals, Inc.
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246 than 20 years) also declined from 5.0 percent to 3.9 percent (3) during this same time period. The typical age at which women now give birth is between 25 and 34 years (3). In a study examining socioeconomic status and rates of breastfeeding in Australia, Amir and Donath (4) found that mothers living in the most deprived neighborhoods were less likely to be breastfeeding at 6 months compared with mothers living in more advantaged areas. In a review of the literature on the factors associated with breastfeeding at 6 months, Forster, McLachlan and Lumley (5) found that lower income, returning to work, perception of lack of breastfeeding support, lower infant birthweight, cesarean section, and admission to special care nursery were negatively associated with breastfeeding duration. Factors positively associated with breastfeeding at 6 months included higher maternal education, not smoking, being married, or not being single. A consistent finding is that younger maternal age is associated with shorter duration of breastfeeding (5). Although this observation is frequently reported, few studies have explored what lies beneath this finding, in particular, the extent to which the association between breastfeeding and maternal age is explained by the greater likelihood of younger mothers experiencing significant social disadvantage. This paper draws on data collected in an Australian population-based survey of women giving birth in South Australia and Victoria to: (1) investigate initiation and duration of breastfeeding among women aged under 25 years and women aged 25 years or older, and (2) assess the extent to which differences in patterns of initiation and duration of breastfeeding associated with maternal age are explained by other social and obstetric risk factors, including exposure to stressful life events and social health issues during and after pregnancy. We hypothesized that women exposed to a greater number of stressful life events and social health issues would be less likely to initiate breastfeeding or to continue breastfeeding at 6 months postpartum, and that the greater likelihood of younger women experiencing multiple social health issues would partially explain the association between maternal age and breastfeeding initiation and duration.
Methods Sample Questionnaires together with an invitation to participate were mailed to all women who gave birth in Victoria and South Australia in September/October 2007, excluding those who had a stillbirth, or whose
baby was known to have died. Births in Victoria and South Australia accounted for 31.3 percent of all births in Australia in 2007. All public and private hospitals with births in the study period (n = 110) and home birth practitioners in both states agreed to participate by mailing questionnaires to women at five to 6 months postpartum. One small hospital later withdrew. The invitation package included an explanation of the study in six community languages (Arabic, Vietnamese, Cantonese, Mandarin, Somali, and Turkish). Two reminders were sent at 2-week intervals; the second of these included a repeat copy of the questionnaire. Research ethics approval was obtained from the ethics committee of the Victorian Department of Human Services, the South Australian Department of Health, the University of South Australia, the Royal Children’s Hospital, and 10 hospitals.
Questionnaire The questionnaire was designed to explore women’s views and experiences of care during pregnancy, labor, birth, and the first 6 months after birth, and included detailed questions about women’s experiences of postnatal care, maternal sociodemographic characteristics, exposure to stressful life events and social health issues, and maternal and infant health outcomes. Initiation and duration of breastfeeding was assessed based on responses to a series of questions which asked: “While you were in hospital, did you ever breastfeed or give your baby expressed breastmilk?”; “During your first week at home did you breastfeed your baby (please include expressed breastmilk)?”; “Are you continuing to breastfeed your baby (or giving expressed breastmilk)?” and “If you started to breastfeed, and have stopped, how old was your baby when you stopped?” It was not possible to determine if women were exclusively breastfeeding beyond the first week at home after the birth. Babies having some formula feeds and some breastmilk feeds were categorized as breastfed for the purposes of analysis. Measures of socioeconomic status included maternal relationship status, educational attainment (completion of secondary school), total family income before tax, possession of a current health care concession card (an indicator of financial hardship), and health insurance status (private cover/Medicare only). Maternal prepregnant body mass index (BMI) was calculated as the ratio of body weight in kilograms divided by the square of height in meters. Smoking during pregnancy was assessed using a multiple response question to
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determine if women had never smoked, quit before their pregnancy, quit when they found out they were pregnant, or continued to smoke during pregnancy (6). Women who said they had quit before pregnancy or who had never smoked were categorized as not smoking. The questionnaire also included a 23-item inventory for assessing stressful life events and social health issues in the 12 months before the birth, and during the first 6 months postpartum. This inventory drew on items from the Pregnancy Risk Assessment and Monitoring Study (PRAMS) (7), a review of relevant literature, community consultations with Aboriginal organizations and communities in both states, and feedback from women participating in the pilot phase of the study. The 23-item inventory included major life events such as separation and divorce, death of a family member or close friend, moving house, and social health issues such as serious family conflict, having a lot of bills you could not pay, not having enough money to buy food, and legal problems. Further details about this measure are published elsewhere (8). Information was also collected on mode of birth, infant birthweight, length of postnatal hospital stay, infant admissions to neonatal or special care nursery, and whether or not the hospital where women gave birth was accredited with the Baby Friendly Hospital Initiative (BFHI). A measure of women’s overall satisfaction with postnatal care in hospital was obtained by asking: “Overall, how would describe the care you and your baby received in hospital after the birth?” with the following five response options: “very good,” “good,” “mixed,” “poor,” or “very poor.”
Statistical Analysis Data on breastfeeding were analyzed to identify the proportions of women who (1) initiated breastfeeding, (2) continued to breastfeed at 6 weeks postpartum, and (3) continued to breastfeed at 6 months postpartum comparing younger and older women (< 25 years/ ≥ 25 years). Maternal sociodemographic and other factors associated with breastfeeding initiation and duration were analyzed using logistic regression. Covariates were specified a priori and included those that have been found to be significantly associated with the main exposure of interest (age) and the primary outcome (any breastfeeding). Multivariable logistic regression was used to examine the association between maternal age, breastfeeding initiation and breastfeeding at 6 months postpartum adjusting for maternal smoking, measures of socioeconomic status, exposure to social adversity, parity, mode of birth, postnatal length of stay in hospital, and other organizational factors. Compari-
sons are presented using odds ratios and 95 percent confidence intervals. Data were analyzed using STATA version 11.0 (9).
Results Participating hospitals and home birth practitioners identified 8,597 eligible women giving birth in the study period. Excluding questionnaires returned to sender, duplicate responses, and women inadvertently mailed questionnaires who gave birth outside the study period, we conservatively estimate that the response fraction was 51.6 percent (4,366/8,468). However, it is likely to have been higher as several hospitals had problems completing mailouts.
Characteristics of the Sample Women taking part in the survey were largely representative in terms of parity, method of birth, and infant birthweight compared with records for births in the study period collected by the Perinatal Data Collection Unit in Victoria (10) and the Pregnancy Outcome Unit in South Australia (11). However, the following groups were underrepresented when compared with all women who gave birth in Victoria and South Australia during the study period. Younger women (under 25 years) comprised 9.5 percent (416/4,366) of the sample, compared with 16.0 percent of all women giving birth in the study period. In addition, single women (3.3% vs 11.3%), women born overseas of non-English speaking background (12.2% vs 18.1%), and Aboriginal and Torres Strait Islander women were underrepresented (0.8% vs 1.3%). The mean age of women in the sample was 31.7 years (range: 16.0– 46.3 years). The sociodemographic, obstetric, and other characteristics of younger and older women in the sample are shown in Table 1. Compared with older women, younger women were more likely to be unmarried, not to have completed secondary school, have a health care concession card, and not have private health insurance indicating relative social disadvantage. They were also more likely to smoke in pregnancy and to report three or more stressful life events and social issues in the 12 months before their baby was born, and in the first 6 months after the birth. Fewer young women had a cesarean section (23.5 vs 33.7% of older women) and more younger women left hospital within 48 hours of giving birth (31.9 vs 21.5% of older women). Younger women were more likely to have given birth in a BFHI accredited hospital. No differences existed in the proportion of infants admitted to neonatal intensive care/
BIRTH 41:3 September 2014
248 Table 1. Sociodemographic, Obstetric, and Other Characteristics of Younger and Older Women (n = 4,366)
Characteristic
< 25 years
Relationship status Married 175 Living with partner 184 Divorced/separated/ 49 widowed/single Maternal country of birth Australia 340 Overseas-English 14 speaking Overseas-Non52 English speaking Maternal education Completed secondary 228 school Did not complete 180 secondary school Health care concession card Yes 224 No 184 Private health insurance Yes 46 No 360 Household Income (AUD) < $30,000 pa 88 $30,000–$50,000 pa 120 $51,000–$70,000 pa 86 > $70,000 pa 46 Smoking in pregnancy Did not smoke in 261 pregnancy Quit in pregnancy 54 Smoked in pregnancy 92 Parity Primiparous 286 Multiparous 124 BMI before pregnancy < 20 76 20–25 159 > 25 to < 30 80 ≥ 30 55 Method of birth Spontaneous vaginal 256 Operative vaginal 56 Cesarean section (not 30 in labor) Cesarean section (in 66 labor)
≥ 25 years
p*
(42.9) (45.1) (12.0)
3,009 (80.3) < 0.001 630 (16.8) 107 (2.9)
(83.7) (3.5)
3,084 (81.7) < 0.05 248 (6.7)
(12.8)
(55.9) (44.1)
435 (11.7)
3,056 (81.9) < 0.001 676 (18.1)
(54.9) (45.1)
665 (17.8) < 0.001 3,074 (82.2)
(11.3) (88.7)
1,971 (52.7) < 0.001 1,769 (47.3)
(25.9) (35.3) (25.3) (13.5)
254 482 735 1,933
(64.1)
3,100 (84.5) < 0.001
(13.3) (22.6)
(7.5) < 0.001 (14.2) (21.6) (56.8)
278 (7.6) 290 (7.9)
(69.8) (30.2)
1,552 (41.4) < 0.001 2,200 (58.6)
(20.5) (43.0) (21.6) (14.9)
489 1,746 783 509
(62.8) (13.7) (7.4)
1,964 (52.4) < 0.001 518 (13.8) 735 (19.6)
(16.2)
(13.9) < 0.01 (49.5) (22.2) (14.4)
529 (14.1)
(continued)
Table 1. Continued
Characteristic
< 25 years
≥ 25 years
Infant birthweight (grams) < 2,500 17 (4.4) 148 (4.1) 2,500–2,999 59 (15.2) 454 (12.7) 3,000–3,499 140 (36.1) 1,294 (36.2) 3,500–3,999 114 (29.4) 1,219 (34.1) > 4,000 58 (15.0) 464 (13.0) Baby admitted to SCN Yes 80 (19.6) 637 (17.0) No 328 (80.4) 3,103 (83.0) Length of stay in hospital ≤ 24 hr 43 (10.7) 251 (6.8) 25–48 hr 85 (21.2) 542 (14.7) 3 days 101 (25.2) 612 (20.5) 4 days 60 (15.0) 758 (20.5) 5 days 75 (18.70) 1,012 (27.4) 6 days 37 (6.6) 525 (14.2) Gave birth in BFHI hospital Yes 154 (37.8) 817 (21.9) No 254 (62.3) 2,915 (78.1) Stressful life events/social issues in pregnancy None 84 (20.6) 1,309 (35.0) 1–2 issues 165 (40.4) 1,873 (50.0) 3 issues 159 (39.0) 563 (15.0) Stressful life events/social issues in postnatal period None 139 (33.9) 2,047 (54.6) 1–2 issues 176 (42.9) 1,396 (37.2) 3 issues 95 (23.2) 306 (8.2)
p* 0.28
0.19
< 0.001
< 0.001
< 0.001
< 0.001
Denominators vary because of missing values. *Chi-square tests for statistical significance. BMI = Body Mass Index; BFHI = Baby Friendly Hospital Initiative; SCN = special care nursery.
special care nursery or with a low birthweight (< 2,500 grams) comparing younger and older women.
Breastfeeding We analyzed the number of women who initiated and were breastfeeding at 1 week, 6 weeks, and 6 months to examine the rates for younger women compared with older women over these time periods. The denominators used to derive these proportions were the total number of younger and older women in the sample for whom we had both age and infant feeding data. Figure 1 shows the proportions of younger and older women in the total sample who were breastfeeding (any) at each time point. The figure illustrates a widening gap in breastfeeding discontinuation between younger and older women from 1 week after the birth.
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Younger Women and Breastfeeding Complete data are available for breastfeeding initiation for 3,514 participants, and for breastfeeding at 6 months for 3,245 participants. These women did not differ in terms of their sociodemographic characteristics when compared with those who were excluded because of incomplete data. In addition to maternal age as the exposure of main interest, 13 variables, specified a priori, were fitted in a multivariable logistic regression model with breastfeeding initiation as the outcome variable (Table 2). On examining the association between age and breastfeeding initiation, we found that younger women were just as likely to initiate breastfeeding as older women, while adjusting for social and obstetric risk factors, including exposure to stressful life events and social health issues during and after pregnancy (Table 2).
Young Women and Breastfeeding Continuation The same 13 variables with the addition of satisfaction with postnatal care were fitted in a multivariable logistic regression model with maternal age as the exposure 100 90 80 70 60 % 50 40 30 20 10 0
< 25 years ≥ 25 years
In hospital (n = 4154)
1st week (n=4146)
Six weeks (n=3805)
Six months (n=3805)
Fig. 1. Any breastfeeding for young (< 25 years) versus older women (≥ 25 years).
Table 2. Association Between Age and Breastfeeding Initiation (n = 3,514)
Age < 25 years ≥ 25 years (ref)
Initiated BFa
Did not initiate BF
Adjusted OR* (95% CI)
312 (94.8) 3,032 (95.2)
17 (5.2) 153 (4.8)
1.13 (0.63–2.05) 1.00
*Adjusted for relationship status, maternal education, health concession card, private insurance, smoking status, parity, body mass index, method of birth, infant birthweight, admission to special care nursery, length of stay, Baby Friendly Hospital Initiative status of hospital, stressful life events/social issues in pregnancy. aBF = breastfeeding.
of main interest and breastfeeding at 6 months as the outcome variable (Table 3). Younger women had significantly raised odds of not breastfeeding at 6 months postpartum, which were only moderately attenuated by taking other sociodemographic, obstetric, and organizational factors into account (Table 3). After adjusting for other variables in the model, women had raised odds of not breastfeeding at 6 months if they: were aged 25 years or younger; quit smoking or continued to smoke in pregnancy; did not complete secondary school; had a BMI greater than 25 (overweight or obese); gave birth operatively; or rated their hospital postnatal care as less than “very good.”
Discussion Improving breastfeeding duration and exclusivity are global health priorities. Despite Australian government and WHO recommendations for exclusive breastfeeding up to 6 months (12,13), there are marked inequalities in breastfeeding duration. Our findings show that young women were less likely to be breastfeeding at 1 week, 6 weeks, and 6 months postpartum. While young women were just as likely to initiate breastfeeding compared with their older counterparts, a decline in breastfeeding was seen in this group as early as the first week after birth. By 6 months, young women were almost twice as likely to have stopped breastfeeding compared with the older age cohort. The study reveals several factors that may explain why young women are less likely to breastfeed for longer periods. Young women were more likely to be single, on a health care concession card, not to have completed secondary schooling, more likely to smoke, and more likely to be having their first baby. In addition, the regression analysis revealed that not completing secondary schooling and smoking in pregnancy were significantly associated with the discontinuation of breastfeeding at 6 months. Although younger women were significantly more likely to experience multiple stressful life events and social health issues in pregnancy and the postpartum period compared with their older counterparts, there was no association between stressful life events and social health issues in pregnancy and breastfeeding cessation. Yelland et al suggest that pregnant women experiencing complex life events are at a double disadvantage in that they are more likely to receive care that is not matched to their needs. This analogy of double disadvantage could be applied equally to younger women’s experience of advice and support with regard to breastfeeding. These authors recommend the development of tailored approaches to perinatal care that specifically address the needs of vulnerable women. Young women
BIRTH 41:3 September 2014
250 Table 3. Factors Associated with Not Breastfeeding at 6 Months (n = 3,245)
Age < 25 years ≥ 25 years (ref) Relationship status Married (ref) Partner/defacto Not partnered Maternal education Completed Year 12 (ref) Did not complete year 12 Health care concession card No (ref) Yes Private health insurance Yes (ref) No Smoking in pregnancy No (ref) Quit in pregnancy Smoked in pregnancy Parity Primiparous (ref) Multiparous BMI before pregnancy < 20 20–25 (ref) > 25 to < 30 ≥ 30 Method of birth Spontaneous vaginal (ref) Operative vaginal Cesarean (not in labor) Cesarean (in labor) Infant birthweight (grams) < 2,500 2,500–2,999 3,000–3,499 (ref) 3,500–3,999 4,000+ Baby admitted to SCN No (ref) Yes Length of stay in hospital < 24 hr 2 days
Breastfeeding (n = 2,036)
Not breastfeeding (n = 1,209)
125 (43.0) 1,911 (64.7)
166 (57.0) 1,043 (35.3)
1.76 (1.34–2.33) 1.00
1,656 (65.2) 335 (54.8) 45 (48.4)
885 (34.8) 276 (45.2) 48 (51.6)
1.00 1.06 (0.87–1.30) 1.11 (0.69–1.78)
1,741 (65.9) 295 (49.0)
902 (34.1) 307 (51.0)
1.00 1.54 (1.27–1.88)
1,699 (64.7) 337 (54.5)
928 (35.3) 281 (45.5)
1.00 1.02 (0.83 to 1.26)
1,105 (67.0) 931 (58.3)
544 (33.0) 665 (41.7)
1.00 1.08 (0.90–1.30)
1,805 (65.9) 125 (50.6) 106 (40.9)
934 (34.1) 122 (49.4) 153 (59.1)
1.00 1.59 (1.20–2.09) 1.97 (1.48–2.62)
867 (60.0) 1,169 (65.0)
579 (40.0) 630 (35.0)
1.00 0.90 (0.76–1.07)
308 1,088 414 226
(65.3) (68.0) (57.0) (50.5)
164 511 312 222
(34.8) (32.0) (43.0) (49.6)
1.06 (0.84–1.32) 1.00 1.55 (1.28–1.87) 1.87 (1.50–2.34)
1,171 256 338 271
(66.6) (56.9) (59.0) (58.5)
588 194 235 192
(33.4) (43.1) (41.0) (41.5)
1.00 1.51 (1.20–1.91) 1.40 (1.12–1.76) 1.26 (0.98–1.61)
67 250 733 705 281
(51.9) (59.7) (62.3) (65.3) (63.9)
62 169 444 375 159
(48.1) (40.3) (37.7) (34.7) (36.1)
1.25 1.06 1.00 0.89 0.83
Adjusted OR (95% CI)
(0.83–1.88) (0.83–1.34) (0.74–1.06) (0.65–1.06)
1,720 (64.0) 316 (56.5)
966 (36.0) 243 (43.5)
1.00 1.11 (0.90–1.37)
142 (64.8) 303 (60.0)
77 (35.2) 202 (40.0)
0.98 (0.69–1.38) 1.17 (0.90–1.52) (continued)
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Table 3. Continued
Breastfeeding (n = 2,036) 3 days (ref) 346 (63.4) 4 days 421 (64.8) 5 days 567 (64.2) 6+ days 257 (58.1) Gave birth in BFHI hospital Yes 420 (56.2) No (ref) 1,616 (64.7) Stressful life events/social issues in the postnatal period None (ref) 1,139 (66.0) 1–2 736 (60.2) 3 or more 161 (54.6) Overall rating of hospital postnatal care “Very good” (ref) 1,266 (65.3) Less than “very good” 673 (34.7)
Not breastfeeding (n = 1,209) 200 229 316 185
Adjusted OR (95% CI)
(36.6) (35.2) (35.8) (41.9)
1.00 1.06 (0.82–1.37) 1.05 (0.82–1.36) 1.17 (0.86–1.59)
327 (43.8) 882 (35.3)
0.84 (0.70–1.01) 1.00
588 (34.1) 487 (39.8) 134 (45.4)
1.00 1.12 (0.96–1.32) 1.08 (0.82–1.42)
770 (60.0) 536 (41.0)
1.00 1.19 (1.02–1.39)
BMI = Body Mass Index; BFHI = Baby Friendly Hospital Initiative; SCN = special care nursery.
experiencing multiple stressful life events and social health issues are one such group who may benefit from individualized breastfeeding advice and support (14). In a systematic review examining the nature of effective breastfeeding support for adolescents, Hall Moran and colleagues (15) found evidence that specific and targeted education programs for adolescents may improve breastfeeding initiation and continuation rates. In addition, Hall Moran et al identified five types of support, and of these, adolescents found emotional, network, and esteem support the most helpful. Biro suggests that midwives may be well-placed to help establish breastfeeding support programs, which have shown some promise in areas where breastfeeding initiation and duration are not high (16,17). Others have suggested working with groups (including younger women) at greater risk of breastfeeding cessation and testing interventions that have been shown to be successful elsewhere (5). In a paper on the inequalities and inequities in breastfeeding, Cattaneo challenges health professionals that they are failing in their responsibilities if they do not act to remove the barriers for all mothers in accessing good quality breastfeeding support (18). Cattaneo also suggests breastfeeding inequities will only be reduced if strategies to support women to breastfeed actively target women from socially disadvantaged backgrounds more so than the general population, that is, care and support should be proportionate to need (18). He reports on several systematic reviews of interventions which have been shown to be effective at increasing breastfeeding rates, including professional and peer support and what constitutes effective support from the mother’s perspective. Similarly, Amir and
Donath (4) suggest that breastfeeding support and promotion should focus on groups with low rates of breastfeeding. Meedya, Fahy and Kable (19) also recommend that midwives focus their education and support on young mothers and those from low socioeconomic backgrounds. Viner et al suggest that improving adolescent health generally requires structural changes to improve education and employment together with supportive families, peers, and school environments (20). Amir and Donath in their critique of breastfeeding and socioeconomic factors also suggest a policy approach to acting on increasing health inequalities (4). Although health care professionals have a significant role to play, they cannot reduce breastfeeding inequalities alone. As Viner et al point out, youth health and wellbeing should be policy priorities across all government sectors (20). In a report to the National Youth Affairs Research Scheme, Loxton and colleagues propose several evidence-based strategies to address service delivery barriers for young pregnant women and mothers (21). They recommend among other things locating care in local communities, developing accessible “one-stop” shops or hubs with a variety of services, and follow-up care incorporating home visits, telephone calls, and SMS communication technology. In addition, they recommend addressing young women’s health literacy needs, the establishment of formal peer support programs and specialized in-school programs, and the development and implementation of a set of best practice principles for working with young pregnant women and mothers. The survey provided an opportunity to examine aspects of the organization of postnatal care and care
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252 provision. Young women were more likely to leave hospital within 48 hours of birth when compared with women aged 25 years or older. However, a shorter postnatal hospital stay was not associated with breastfeeding cessation, supporting the findings of three previous Victorian population-based surveys of recent mothers (22), and a systematic review of randomized trials evaluating early postnatal discharge for healthy mothers of term infants (23). Younger women were also far more likely to give birth in a BFHI hospital yet no association existed between birth hospital accreditation and duration of breastfeeding. In a recent Australian population-based study, Brodribb et al found that evidence-based supportive breastfeeding practices rather than BFHI accreditation per se positively influenced breastfeeding rates at one and 4 months (24). How women experienced the care they received in hospital after birth was associated with breastfeeding duration, with those rating their care as less than “very good” more likely to have stopped breastfeeding by 6 months.
collection (30). Potential misclassification of infant feeding at particular time points cannot be overlooked. However, while Li, Scanlon and Serdula (31) found that validity and reliability of maternal recall for the age at introduction of food and fluids other than breastmilk was less accurate, women’s recall for breastfeeding initiation and duration has been found to be accurate (31). Although we acknowledge that much of the literature we have referred to focuses on adolescent mothers and interventions that may increase breastfeeding duration in this group, our study suggests that similar factors are operating in the group of mothers we defined as young (i.e., < 25 years). In the context of the increasing age profile of childbearing women, it is important to recognize that even women giving birth in their early twenties may have different ideas, beliefs, and behaviors compared with their older counterparts, and may need additional support tailored to their particular circumstances to achieve rates of breastfeeding comparable to older women.
Strengths and Limitations
Conclusions
Although the response fraction of 51.6 percent was less than that in previous population-based surveys of recent mothers in Victoria (25–27), participants were representative in terms of important obstetric characteristics such as parity, method of birth, and infant birthweight. However, young women, single women, Aboriginal and Torres Strait Islander women, and those from a nonEnglish-speaking background were underrepresented. Prevalence estimates for breastfeeding initiation and duration must be considered in the light of the underrepresentation of these groups, and especially the underrepresentation of young women. It is possible that the young women who did respond to the survey differ from those who did not and therefore possible that the prevalence of breastfeeding was overestimated for young women specifically. Based on the results of the Australian National Infant Feeding survey (1), the proportion of women giving any breastmilk to their infants at 6 months was 39.1 percent. In our study, the proportion of young women reporting that they were giving any breastmilk at 6 months was 43.0 percent. Although the response fraction was lower than anticipated, this is unlikely to have had a marked effect on estimates of association. Two recent studies provide robust evidence to support the assumption that estimates of association between variables remain reliable in studies with much lower response fractions than in the current study (28,29). To address some of the methodological limitations of surveying women about infant feeding practices, Tomeo and colleagues have advocated for prospective data
Although young women in Australia are as likely to initiate breastfeeding compared with their older counterparts, they are more likely to cease breastfeeding earlier with the decline occurring as early as 1 week postpartum. Although health care professionals have a significant role to play, they cannot reduce breastfeeding inequalities alone. Given the complexity of young childbearing women’s lives, supporting younger women to breastfeed will require a multisectorial approach that addresses social disadvantage and resulting health inequalities.
Funding We acknowledge the funding provided by the National Health and Medical Research Council (ID: 433012), the Victorian Department of Human Services, the South Australian Department of Health, and the Victorian Government’s Operational Infrastructure Support Program. SB was supported by a National Health and Medical Research Council Career Development Fellowship (ID: 491205, 2008–2011) and currently holds an Australian Research Council Future Fellowship.
Acknowledgments We are most grateful to the thousands of women who participated in the survey at a particularly busy time of their lives, and to the hospitals in South Australia and
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Victoria who helped in mailing out questionnaires. We are grateful to the following large team of study investigators who have contributed to the development of the research protocol and conduct of the study: Peter Baghurst, Jane Gunn, Jeffrey Robinson, Georgie Stamp, Euan Wallace; and acknowledge with gratitude the significant contribution of the following staff in the conduct of the study: Georgina Sutherland, Katherine Chisholm, Maggie Flood, Monique Keel, Jenny Kelly, Penny Marlowe, Renee Paxton, and Jan Wiebe. We thank the other members of the Healthy Mothers Healthy Families Research group for their ongoing support of the study.
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17.
18.
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