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Access to Obstetric Care in the United States from the National Health Interview Survey Jamie E. Anderson
a
a
University of California, San Diego Medical School , San Diego , California , USA Published online: 09 Jan 2014.
To cite this article: Jamie E. Anderson (2014) Access to Obstetric Care in the United States from the National Health Interview Survey, Social Work in Public Health, 29:2, 141-147, DOI: 10.1080/19371918.2013.775875 To link to this article: http://dx.doi.org/10.1080/19371918.2013.775875
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
Social Work in Public Health, 29:141–147, 2014 Copyright © Taylor & Francis Group, LLC ISSN: 1937-1918 print/1937-190X online DOI: 10.1080/19371918.2013.775875
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Access to Obstetric Care in the United States from the National Health Interview Survey Jamie E. Anderson University of California, San Diego Medical School, San Diego, California, USA
This cross-sectional observational study uses data from the National Health Interview Survey from 1999 to 2006 to identify demographic factors associated with whether pregnant women have seen an OB/GYN within the last year. This analysis includes 2,748 women who were pregnant at the time of the interview. In total, 86.3% of women had seen an OB/GYN in the previous year. Women who are uninsured, have not completed high school, are Asian, or who live in the Midwest or Western regions may be at lower odds for receiving prenatal care. This study identifies vulnerable populations that may not be receiving adequate obstetric care. Keywords: Health care access, health care disparities, prenatal care, minority health, pregnancy outcomes
INTRODUCTION Health disparities continue to exist in pregnancy outcomes in the United States. Disparities, particularly on the basis of race/ethnicity, include differing outcomes of congenital abnormalities, fetal demise, preterm births, fetal growth restriction, and maternal mortality and morbidity (Bryant et al., 2010). Socioeconomic status and other social circumstances also contribute to these differences (Bryant et al., 2010). Region of residence may also be a factor in disparities of pregnancy outcomes, with a higher risk of neonatal mortality to women from rural areas (Hughes et al., 2008). Lack of prenatal care has been shown to be a major determinant of increasing the risk of adverse pregnancy outcomes (Bryant et al., 2010). Women who receive no prenatal care may have a two- to fourfold increased risk for negative birth outcomes compared to women who receive any care (Taylor et al., 2005). Disparities are also evident in terms of access to prenatal care. Race has been seen to be an important factor in access to prenatal care; White women and Asian/Pacific Islanders are most likely to receive prenatal care in the first trimester, whereas women who fail to receive prenatal care are more likely to be non-White (Agency for Healthcare Research and Quality [AHRQ], 2008; Bryant et al., 2010). Some contributors to late entry to prenatal care may include lack of education, lack of insurance coverage, attitudes about pregnancy, and perceptions This is an unfunded study in which the analysis, interpretations, and conclusions are the sole opinion of the author, not the National Center for Health Statistics, which was responsible for data collection. Address correspondence to Jamie E. Anderson, MPH, University of California, San Diego, 9500 Gilman Drive, San Diego, CA 92093, USA. E-mail: [email protected]
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of health care and staff (Bryant et al., 2010). Type of health insurance may also play a factor; one study found that private health insurance improves access to early prenatal care compared with public health insurance (Bengiamin et al., 2010). Of those eligible for Medicaid, enrollment before pregnancy also helps ensure that pregnant women seek prenatal care in the first trimester (Rosenberg et al., 2007). Still, more research must be done at the national level to understand barriers to access to adequate prenatal care to ultimately reduce disparities of pregnancy outcomes. Utilizing data from the National Health Interview Survey from 1999 to 2006, this study seeks to determine potential demographic predictors of whether pregnant women see an OB/GYN before giving birth. Demographic predictors analyzed include age, race, ethnicity, citizenship, poverty level, marital status, insurance status, region of residence, education level, and birthplace (inside or outside the United States).
METHOD Participants and Database We obtained data from the National Health Interview Survey, a multipurpose interview conducted by the National Center for Health Statistics at the Center for Disease Control and Prevention (CDC) annually since 1957. Data included demographic information from women who reported they were pregnant at the time of the survey. Data includes surveys conducted annually from 1999 to 2006. Of the 291,512 households (a total of 757,797 individuals) that were sampled from 1999 to 2006, this analysis includes 2,748 women who were pregnant at the time of the interview. The data we obtained for each of these women included whether they have seen an OB/GYN in the past year, age, race, region of residence, type of insurance, whether they were uninsured at some point during the past year, whether their income was above, at, or below the poverty threshold, highest educational level attained, marital status, citizenship, and whether or not they were born in the United States. Each of these variables was considered as a categorical factor. This analysis was exempt from Institutional Review Board review.
Statistical Analysis Our primary outcome was whether the woman who was pregnant at the time of interview had seen an OB/GYN in the past 12 months. We used multiple logistic regressions to examine the relationship between this outcome and various demographic factors. We first used separate models for each demographic factor against our outcome and then fitted various models combining variables of interest. After fitting a model of all variables of interest, we systematically dropped variables and calculated likelihood ratio tests. We then performed a forward and backward stepwise variable selection with likelihood ratio tests. After locking in race, ethnicity, and insurance status into the model, region of residence and highest level of education attained were included in the model via stepwise variable selection. All other variables were insignificant in predicting whether a pregnant woman had a visit with an OB/GYN in the past year. Forward and backward stepwise models included the same variables. Models including interaction terms were also considered and likelihood ratio tests were performed. To check the fit of these models, Pearson’s goodness-of-fit test and Hosmer-Lemeshow goodness-of-fit tests were used. Residuals, leverage, and deviance were also explored to evaluate the fit of the model. The Akaike Information Criterion (AIC) values of all the above models were compared and the model with the lowest AIC value was one chosen through forward stepwise variable selection. Based on the variables of interest (race, ethnicity, and insurance status) and previous information
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about access to obstetric care, our forward stepwise model was chosen for this analysis. It included the variables race, ethnicity, type of insurance, region of residence, and education level.
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RESULTS Between 1999 and 2006, 2,748 pregnant women were interviewed in the National Health Interview Survey. Of these, 86.3% (n D 2,371, 95% confidence interval [CI] [84.9, 87.5]) reported that they had seen an OB/GYN in the past 12 months. The mean age of women included in the survey was 27.9 .SD D 5:9/, with a minimum age of 18 and a maximum age of 49 (Table 1). Of those included in the survey, 74.0% reported they were White, 16.3% reported they were Black, 3.3% reported they were Asian, and 6.5% reported they were American Indian, Native Alaskan, multiethnic, or other. The highest proportion of women included in the survey was from the South (37.2%), whereas 24.7% were from the West, 22.0% were from North Central/Midwest, and 16.1% were from the Northeast. Most women had private insurance (52.5%), although a large proportion had Medicaid (27.8%). Women with other types of government insurance made up 6.4% of those surveyed, whereas 12.9% of women were uninsured. A large proportion of women were U.S. citizens (81.9%), most were born in the United States (75.5%), and most were married at the time of the survey (67.9%). The highest proportion of women reported high school as the highest level of educational attainment (56.1), but 19.2% of women did not complete high school, 16.6% of women completed their bachelor’s degree, and 7.4% of women completed a master’s degree or higher. Most women reported they were at or above the poverty threshold (63.9%). Our final regression model included race, ethnicity, type of insurance, highest educational level attained, and region of residence. In this model, only Asian women had a statistically significant odds ratio (when compared to White women). Asian women were found to be 47% less likely than white women to have gone to an OB/GYN in the past year (p D :04, 95% CI [0.29, 0.96]; see Table 2). The relative odds of Black women seeing an OB/GYN in the past year were lower compared to White women (OR D .76, p D :11), and the relative odds of American Indian, Native Alaskan, multiethnic group, or other of seeing an OB/GYN in the past year were higher compared to White women (OR D 1.28, p D :30), but these were not statistically significant. Uninsured women were 77% less likely to see an OB/GYN in the past year compared to women with private insurance (95% CI [0.2, 0.3], p < 0:01). Women with Medicaid or other types of government insurance showed no significant difference compared to women with private insurance. Region of residence was also an important predictor of whether a woman had a visit with an OB/GYN during the past year. Compared to women in the Northeast, women in the North Central/Midwest region were 53% less likely to have visited an OB/GYN in the past year (95% CI [0.3, 0.7], p < 0:01). Women living in the West were 54% less likely to have visited an OB/GYN in the past year compared to women in the Northeast (95% CI [0.3, 0.7], p < 0:01). Women in the South were found to be 7% less likely than women in the Northeast to have visited an OB/GYN, but this was not statistically significant .p D :74/. Education level was also a significant factor in predicting whether or not women have seen an OB/GYN in the past year. Compared to women who did not complete high school, women who have completed high school were 1.9 times more likely to have seen an OB/GYN (95% CI [1.4, 2.5], p < 0:01). Women who completed their bachelor’s degree were 3.2 times more likely to have seen an OB/GYN (95% CI [2.0, 5.2], p < 0:01), and those with a master’s degree or higher were 2.5 times more likely to have seen an OB/GYN (95% CI [1.4. 4.6], p < 0:01) compared with those who have not completed high school.
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TABLE 1 Population Characteristics
Demographics Age 18–23 24–27 28–32 >32 Race % (n) White Black Asian American Indian, Native Alaskan, multi-ethnic group, other Hispanic/Spanish origin % Not of Hispanic/Spanish origin Hispanic/Spanish origin Region of residence % Northeast North Central/Midwest South West Insurance status % Private insurance Medicaid Other government insurance Uninsured Unknown Marital status % Married Never married Widowed, divorced, or separated Unknown Citizenship status % U.S. citizen Non-U.S. citizen Born in the United States % Yes No Highest education completed % Did not complete high school Completed high school Bachelor’s degree Master’s degree or higher Unknown Poverty level % At or above poverty threshold Below poverty threshold Unknown
Saw OB/GYN (n D 2,371)
Did not see OB/GYN (n D 377)
Total (N D 2,748)
26.3 23.6 22.8 27.3
30.2 21.5 20.4 27.9
26.8 23.3 22.5 27.4
74.5 16.0 3.1
70.8 18.0 4.2
74.0 16.3 3.3
6.4
6.9
6.5
73.4 26.6
58.9 41.1
71.4 28.6
17.1 21.5 38.3 23.1
9.8 24.9 30.5 34.8
16.1 22.0 37.2 24.7
55.7 27.7 6.5 9.7 0.5
32.1 28.4 6.4 32.6 0.5
52.5 27.8 6.4 12.9 0.5
68.8 24.3 6.5 0.4
62.1 30.0 7.4 0.5
67.9 25.1 6.6 0.4
84.1 15.9
68.4 31.7
81.9 18.1
77.7 22.3
61.5 38.5
75.5 24.5
16.5 56.9 18.1 7.8 0.7
36.3 50.9 7.7 4.2 0.8
19.2 56.1 16.6 7.4 0.7
65.3 15.2 19.5
55.4 23.6 21.0
63.9 16.4 19.7
p Value
0.34
0.42
< 0.01
< 0.01
< 0.01
0.08
< 0.01
< 0.01
< 0.01
< 0.01
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TABLE 2 Crude and Adjusted Relative Odds of Seeing an OB/GYN Adjusteda
Crude
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OR Race White (reference) Black Asian American Indian, Native Alaskan, multiethnic group, other Hispanic/Spanish origin Not Hispanic or Spanish origin (reference) Hispanic or Spanish origin Insurance type Private insurance (reference) Medicaid Other government insurance Uninsured Unknown Education level Did not complete high school (reference) Completed high school Completed bachelor’s degree Completed master’s or higher Other Region of residence Northeast (reference) North Central/Midwest South West
95% CI
p Value
OR
95% CI
0.44 1.0 0.8 0.7
[0.6, 1.1] [0.4, 1.2]
0.25 0.21
0.9
[0.6, 1.4]
0.58 0.01
1.0 0.5
[0.4, 0.7]
< 0.01 0.06
1.0 0.6 0.6 0.2 0.5
[0.4, [0.4, [0.1, [0.1,
0.7] 0.9] 0.2] 2.3]
< 0.01 0.03 < 0.01 0.38 0.04
1.0 2.5 5.2 4.1 2.0
[1.9, [3.4, [2.4, [0.6,
3.1] 7.9] 7.0] 6.9]
< 0.01 < 0.01 < 0.01 0.28 0.02
1.0 0.5 0.7 0.4
[0.3, 0.7] [0.5, 1.1] [0.3, 0.6]
< 0.01 0.10 < 0.01
p Value 1.00
1.0 0.8 0.53
[0.5, 1.1] [0.29, 0.96]
0.11 0.04
1.3
[0.8, 2.0]
0.30 0.49
1.0 0.9
[0.7, 1.2]
0.53 < 0.01
1.0 0.8 0.7 0.2 0.7
[0.6, [0.4, [0.2, [0.1,
1.1] 1.1] 0.3] 3.1]
0.16 0.12 < 0.01 0.61 < 0.01
1.0 1.9 3.2 2.5 1.3
[1.4, [2.0, [1.4, [0.4,
2.5] 5.2] 4.6] 4.5]
< 0.01 < 0.01 < 0.01 0.71 < 0.01
1.0 0.5 0.9 0.5
[0.3, 0.7] [0.6, 1.4] [0.3, 0.7]
< 0.01 0.74 < 0.01
OR D odds ratio; CI D confidence interval. model includes race, Hispanic or Spanish origin, insurance type, education level, and region of residence.
a Adjusted
A Pearson’s goodness-of-fit test was performed and suggested that this model is a good fit ( 2 D 284:08, p D :17). Further exploration of residuals, leverage, and influence suggested acceptable fit of our model.
DISCUSSION The results of this study suggest that race and other socioeconomic factors such as poverty may not play as direct of a role in access to obstetric care for pregnant women compared to insurance status, region, and education level. Asian women were 47% less likely to see an OB/GYN compared to white women .p D :04/, but this may not be statistically significant because the confidence interval approaches one. No other race was significantly different in terms of whether they were more or less likely to have seen an OB/GYN compared to White women. Type of insurance was not a significant factor. However, women without insurance were 77% less likely to visit an OB/GYN compared to those with private health insurance .p < 0:01/. Region of residence
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also played an important role in predicting this outcome, with women living in the Northeast the most likely to visit an OB/GYN, and women in the North Central/Midwest (OR D .53) and Western regions (OR D .54) the least likely to visit an OB/GYN. Women who were most likely to have visited an OB/GYN were those who have completed high school or master’s degrees or higher compared with women who have not completed high school. Women with higher levels of education may thus have better access to obstetric care, independent of other variables. There are several factors that limit the results of this study. First, this study is based on the results of a phone interview; all data were self-reported by those participating in the survey and were not confirmed via other methods. Recall bias or error may be present in this respect. Although the women included reported they were pregnant, the survey does not confirm their pregnancy status nor does it indicate a woman’s stage of pregnancy, her parity, or other information. This study also assumes that all women who are pregnant should have seen an OB/GYN in the past year and assumes that the factors affecting this decision are related to demographic factors and type of insurance. This study also does not take into account whether a pregnant woman intends to seek care from an OB/GYN, only if she has at the time of the survey. It also does not consider whether a woman has sought care from another primary care provider or another health provider, such as a general practitioner or a midwife. This study is also limited in the way it defines certain variables. For example, race includes the categories White, Black, Asian, American Indian, Native Alaskan, multiethnic group, or other. Whether a person is of Hispanic or Spanish origin is a separate variable. Nuances in these definitions may not accurately categorize individuals. Although Asian women seem to be at a higher risk for not receiving prenatal care in this analysis, Asian women represent a small number of this study population.
CONCLUSION This study suggests that race, health insurance, region of residence, and education level are all associated with access to obstetric care for pregnant women. This study provides evidence that pregnant women who have not completed high school, who are Asian, who do not have health insurance, and who live in the Midwest and West may be at the highest risk for not receiving prenatal care during pregnancy. In working to increase equality of access to care, especially for pregnant women, further targeted research in these areas may be necessary to determine appropriate interventions. Specifically, more research should be conducted to see what factors might make Asian women at a higher risk for not receiving prenatal care, especially because though this analysis suggests that Asian women are less likely to visit an OB/GYN, the National Healthcare Disparities Report shows that Asian/Pacific Islander women (and White women) are actually most likely to receive prenatal care (AHRQ, 2008). Although this study does not consider obstetric outcomes as a result of access to obstetric care, it nevertheless provides an important picture of which women are able to obtain obstetric care and which women may be at the highest risk for negative outcomes. Although this study also does not consider whether a woman will see an OB/GYN and if so, in what trimester, the results still suggest that some factors, especially a lack of health insurance, prevent women from receiving prenatal care. In addition to improving maternal and infant outcomes, prenatal care can improve overall maternal health, increase subsequent use of pediatric care, and may allow women at social or economic risk an entry point into the health care system (Rosenberg et al., 2007). Further targeted examination of these results is the next step in developing appropriate, targeted interventions to ultimately decrease disparities in maternal and infant outcomes.
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REFERENCES Agency for Healthcare Research and Quality. (2008). National healthcare disparities report 2007. Rockville, MD: Author. Bengiamin, M. I., Capitman, J. A., & Ruwe, M. B. (2010). Disparities in initiation and adherence to prenatal care: Impact of insurance, race-ethnicity and nativity. Maternal and Child Health Journal, 14, 618–664. Bryant, A. S., Worjoloh, A., Caughey, A. B., & Washington, A. E. (2010). Racial/ethnic disparities in obstetric outcomes and care: Prevalence and determinants. American Journal of Obstetrics and Gynecology, 335–343. Hughes, S., Zweifler, J. A., Garza, A., Stanich, & M. A. (2008). Trends in rural and urban deliveries and vaginal births: California 1998–2002. National Rural Health Association, 24(4), 416–422. Rosenberg, D., Handler, A., Rankin, K. M., Zimbeck, M., & Adams, E. K. (2007). Prenatal care initiation among very low-income women in the aftermath of welfare reform: Does pre-pregnancy Medicaid coverage make a difference? Maternal and Child Health Journal, 11, 11–17. Taylor, C. R., Alexander, G. R., & Hepworth, J. T. (2005). Clustering of U.S. women receiving no prenatal care: Differences in pregnancy outcomes and implications for targeting interventions. Maternal and Child Health Journal, 9(2), 125–133.
Social Work in Public Health Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/whsp20
Access to Obstetric Care in the United States from the National Health Interview Survey Jamie E. Anderson
a
a
University of California, San Diego Medical School , San Diego , California , USA Published online: 09 Jan 2014.
To cite this article: Jamie E. Anderson (2014) Access to Obstetric Care in the United States from the National Health Interview Survey, Social Work in Public Health, 29:2, 141-147, DOI: 10.1080/19371918.2013.775875 To link to this article: http://dx.doi.org/10.1080/19371918.2013.775875
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
Social Work in Public Health, 29:141–147, 2014 Copyright © Taylor & Francis Group, LLC ISSN: 1937-1918 print/1937-190X online DOI: 10.1080/19371918.2013.775875
Downloaded by [University of Toronto Libraries] at 16:56 31 October 2014
Access to Obstetric Care in the United States from the National Health Interview Survey Jamie E. Anderson University of California, San Diego Medical School, San Diego, California, USA
This cross-sectional observational study uses data from the National Health Interview Survey from 1999 to 2006 to identify demographic factors associated with whether pregnant women have seen an OB/GYN within the last year. This analysis includes 2,748 women who were pregnant at the time of the interview. In total, 86.3% of women had seen an OB/GYN in the previous year. Women who are uninsured, have not completed high school, are Asian, or who live in the Midwest or Western regions may be at lower odds for receiving prenatal care. This study identifies vulnerable populations that may not be receiving adequate obstetric care. Keywords: Health care access, health care disparities, prenatal care, minority health, pregnancy outcomes
INTRODUCTION Health disparities continue to exist in pregnancy outcomes in the United States. Disparities, particularly on the basis of race/ethnicity, include differing outcomes of congenital abnormalities, fetal demise, preterm births, fetal growth restriction, and maternal mortality and morbidity (Bryant et al., 2010). Socioeconomic status and other social circumstances also contribute to these differences (Bryant et al., 2010). Region of residence may also be a factor in disparities of pregnancy outcomes, with a higher risk of neonatal mortality to women from rural areas (Hughes et al., 2008). Lack of prenatal care has been shown to be a major determinant of increasing the risk of adverse pregnancy outcomes (Bryant et al., 2010). Women who receive no prenatal care may have a two- to fourfold increased risk for negative birth outcomes compared to women who receive any care (Taylor et al., 2005). Disparities are also evident in terms of access to prenatal care. Race has been seen to be an important factor in access to prenatal care; White women and Asian/Pacific Islanders are most likely to receive prenatal care in the first trimester, whereas women who fail to receive prenatal care are more likely to be non-White (Agency for Healthcare Research and Quality [AHRQ], 2008; Bryant et al., 2010). Some contributors to late entry to prenatal care may include lack of education, lack of insurance coverage, attitudes about pregnancy, and perceptions This is an unfunded study in which the analysis, interpretations, and conclusions are the sole opinion of the author, not the National Center for Health Statistics, which was responsible for data collection. Address correspondence to Jamie E. Anderson, MPH, University of California, San Diego, 9500 Gilman Drive, San Diego, CA 92093, USA. E-mail: [email protected]
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of health care and staff (Bryant et al., 2010). Type of health insurance may also play a factor; one study found that private health insurance improves access to early prenatal care compared with public health insurance (Bengiamin et al., 2010). Of those eligible for Medicaid, enrollment before pregnancy also helps ensure that pregnant women seek prenatal care in the first trimester (Rosenberg et al., 2007). Still, more research must be done at the national level to understand barriers to access to adequate prenatal care to ultimately reduce disparities of pregnancy outcomes. Utilizing data from the National Health Interview Survey from 1999 to 2006, this study seeks to determine potential demographic predictors of whether pregnant women see an OB/GYN before giving birth. Demographic predictors analyzed include age, race, ethnicity, citizenship, poverty level, marital status, insurance status, region of residence, education level, and birthplace (inside or outside the United States).
METHOD Participants and Database We obtained data from the National Health Interview Survey, a multipurpose interview conducted by the National Center for Health Statistics at the Center for Disease Control and Prevention (CDC) annually since 1957. Data included demographic information from women who reported they were pregnant at the time of the survey. Data includes surveys conducted annually from 1999 to 2006. Of the 291,512 households (a total of 757,797 individuals) that were sampled from 1999 to 2006, this analysis includes 2,748 women who were pregnant at the time of the interview. The data we obtained for each of these women included whether they have seen an OB/GYN in the past year, age, race, region of residence, type of insurance, whether they were uninsured at some point during the past year, whether their income was above, at, or below the poverty threshold, highest educational level attained, marital status, citizenship, and whether or not they were born in the United States. Each of these variables was considered as a categorical factor. This analysis was exempt from Institutional Review Board review.
Statistical Analysis Our primary outcome was whether the woman who was pregnant at the time of interview had seen an OB/GYN in the past 12 months. We used multiple logistic regressions to examine the relationship between this outcome and various demographic factors. We first used separate models for each demographic factor against our outcome and then fitted various models combining variables of interest. After fitting a model of all variables of interest, we systematically dropped variables and calculated likelihood ratio tests. We then performed a forward and backward stepwise variable selection with likelihood ratio tests. After locking in race, ethnicity, and insurance status into the model, region of residence and highest level of education attained were included in the model via stepwise variable selection. All other variables were insignificant in predicting whether a pregnant woman had a visit with an OB/GYN in the past year. Forward and backward stepwise models included the same variables. Models including interaction terms were also considered and likelihood ratio tests were performed. To check the fit of these models, Pearson’s goodness-of-fit test and Hosmer-Lemeshow goodness-of-fit tests were used. Residuals, leverage, and deviance were also explored to evaluate the fit of the model. The Akaike Information Criterion (AIC) values of all the above models were compared and the model with the lowest AIC value was one chosen through forward stepwise variable selection. Based on the variables of interest (race, ethnicity, and insurance status) and previous information
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about access to obstetric care, our forward stepwise model was chosen for this analysis. It included the variables race, ethnicity, type of insurance, region of residence, and education level.
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RESULTS Between 1999 and 2006, 2,748 pregnant women were interviewed in the National Health Interview Survey. Of these, 86.3% (n D 2,371, 95% confidence interval [CI] [84.9, 87.5]) reported that they had seen an OB/GYN in the past 12 months. The mean age of women included in the survey was 27.9 .SD D 5:9/, with a minimum age of 18 and a maximum age of 49 (Table 1). Of those included in the survey, 74.0% reported they were White, 16.3% reported they were Black, 3.3% reported they were Asian, and 6.5% reported they were American Indian, Native Alaskan, multiethnic, or other. The highest proportion of women included in the survey was from the South (37.2%), whereas 24.7% were from the West, 22.0% were from North Central/Midwest, and 16.1% were from the Northeast. Most women had private insurance (52.5%), although a large proportion had Medicaid (27.8%). Women with other types of government insurance made up 6.4% of those surveyed, whereas 12.9% of women were uninsured. A large proportion of women were U.S. citizens (81.9%), most were born in the United States (75.5%), and most were married at the time of the survey (67.9%). The highest proportion of women reported high school as the highest level of educational attainment (56.1), but 19.2% of women did not complete high school, 16.6% of women completed their bachelor’s degree, and 7.4% of women completed a master’s degree or higher. Most women reported they were at or above the poverty threshold (63.9%). Our final regression model included race, ethnicity, type of insurance, highest educational level attained, and region of residence. In this model, only Asian women had a statistically significant odds ratio (when compared to White women). Asian women were found to be 47% less likely than white women to have gone to an OB/GYN in the past year (p D :04, 95% CI [0.29, 0.96]; see Table 2). The relative odds of Black women seeing an OB/GYN in the past year were lower compared to White women (OR D .76, p D :11), and the relative odds of American Indian, Native Alaskan, multiethnic group, or other of seeing an OB/GYN in the past year were higher compared to White women (OR D 1.28, p D :30), but these were not statistically significant. Uninsured women were 77% less likely to see an OB/GYN in the past year compared to women with private insurance (95% CI [0.2, 0.3], p < 0:01). Women with Medicaid or other types of government insurance showed no significant difference compared to women with private insurance. Region of residence was also an important predictor of whether a woman had a visit with an OB/GYN during the past year. Compared to women in the Northeast, women in the North Central/Midwest region were 53% less likely to have visited an OB/GYN in the past year (95% CI [0.3, 0.7], p < 0:01). Women living in the West were 54% less likely to have visited an OB/GYN in the past year compared to women in the Northeast (95% CI [0.3, 0.7], p < 0:01). Women in the South were found to be 7% less likely than women in the Northeast to have visited an OB/GYN, but this was not statistically significant .p D :74/. Education level was also a significant factor in predicting whether or not women have seen an OB/GYN in the past year. Compared to women who did not complete high school, women who have completed high school were 1.9 times more likely to have seen an OB/GYN (95% CI [1.4, 2.5], p < 0:01). Women who completed their bachelor’s degree were 3.2 times more likely to have seen an OB/GYN (95% CI [2.0, 5.2], p < 0:01), and those with a master’s degree or higher were 2.5 times more likely to have seen an OB/GYN (95% CI [1.4. 4.6], p < 0:01) compared with those who have not completed high school.
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TABLE 1 Population Characteristics
Demographics Age 18–23 24–27 28–32 >32 Race % (n) White Black Asian American Indian, Native Alaskan, multi-ethnic group, other Hispanic/Spanish origin % Not of Hispanic/Spanish origin Hispanic/Spanish origin Region of residence % Northeast North Central/Midwest South West Insurance status % Private insurance Medicaid Other government insurance Uninsured Unknown Marital status % Married Never married Widowed, divorced, or separated Unknown Citizenship status % U.S. citizen Non-U.S. citizen Born in the United States % Yes No Highest education completed % Did not complete high school Completed high school Bachelor’s degree Master’s degree or higher Unknown Poverty level % At or above poverty threshold Below poverty threshold Unknown
Saw OB/GYN (n D 2,371)
Did not see OB/GYN (n D 377)
Total (N D 2,748)
26.3 23.6 22.8 27.3
30.2 21.5 20.4 27.9
26.8 23.3 22.5 27.4
74.5 16.0 3.1
70.8 18.0 4.2
74.0 16.3 3.3
6.4
6.9
6.5
73.4 26.6
58.9 41.1
71.4 28.6
17.1 21.5 38.3 23.1
9.8 24.9 30.5 34.8
16.1 22.0 37.2 24.7
55.7 27.7 6.5 9.7 0.5
32.1 28.4 6.4 32.6 0.5
52.5 27.8 6.4 12.9 0.5
68.8 24.3 6.5 0.4
62.1 30.0 7.4 0.5
67.9 25.1 6.6 0.4
84.1 15.9
68.4 31.7
81.9 18.1
77.7 22.3
61.5 38.5
75.5 24.5
16.5 56.9 18.1 7.8 0.7
36.3 50.9 7.7 4.2 0.8
19.2 56.1 16.6 7.4 0.7
65.3 15.2 19.5
55.4 23.6 21.0
63.9 16.4 19.7
p Value
0.34
0.42
< 0.01
< 0.01
< 0.01
0.08
< 0.01
< 0.01
< 0.01
< 0.01
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TABLE 2 Crude and Adjusted Relative Odds of Seeing an OB/GYN Adjusteda
Crude
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OR Race White (reference) Black Asian American Indian, Native Alaskan, multiethnic group, other Hispanic/Spanish origin Not Hispanic or Spanish origin (reference) Hispanic or Spanish origin Insurance type Private insurance (reference) Medicaid Other government insurance Uninsured Unknown Education level Did not complete high school (reference) Completed high school Completed bachelor’s degree Completed master’s or higher Other Region of residence Northeast (reference) North Central/Midwest South West
95% CI
p Value
OR
95% CI
0.44 1.0 0.8 0.7
[0.6, 1.1] [0.4, 1.2]
0.25 0.21
0.9
[0.6, 1.4]
0.58 0.01
1.0 0.5
[0.4, 0.7]
< 0.01 0.06
1.0 0.6 0.6 0.2 0.5
[0.4, [0.4, [0.1, [0.1,
0.7] 0.9] 0.2] 2.3]
< 0.01 0.03 < 0.01 0.38 0.04
1.0 2.5 5.2 4.1 2.0
[1.9, [3.4, [2.4, [0.6,
3.1] 7.9] 7.0] 6.9]
< 0.01 < 0.01 < 0.01 0.28 0.02
1.0 0.5 0.7 0.4
[0.3, 0.7] [0.5, 1.1] [0.3, 0.6]
< 0.01 0.10 < 0.01
p Value 1.00
1.0 0.8 0.53
[0.5, 1.1] [0.29, 0.96]
0.11 0.04
1.3
[0.8, 2.0]
0.30 0.49
1.0 0.9
[0.7, 1.2]
0.53 < 0.01
1.0 0.8 0.7 0.2 0.7
[0.6, [0.4, [0.2, [0.1,
1.1] 1.1] 0.3] 3.1]
0.16 0.12 < 0.01 0.61 < 0.01
1.0 1.9 3.2 2.5 1.3
[1.4, [2.0, [1.4, [0.4,
2.5] 5.2] 4.6] 4.5]
< 0.01 < 0.01 < 0.01 0.71 < 0.01
1.0 0.5 0.9 0.5
[0.3, 0.7] [0.6, 1.4] [0.3, 0.7]
< 0.01 0.74 < 0.01
OR D odds ratio; CI D confidence interval. model includes race, Hispanic or Spanish origin, insurance type, education level, and region of residence.
a Adjusted
A Pearson’s goodness-of-fit test was performed and suggested that this model is a good fit ( 2 D 284:08, p D :17). Further exploration of residuals, leverage, and influence suggested acceptable fit of our model.
DISCUSSION The results of this study suggest that race and other socioeconomic factors such as poverty may not play as direct of a role in access to obstetric care for pregnant women compared to insurance status, region, and education level. Asian women were 47% less likely to see an OB/GYN compared to white women .p D :04/, but this may not be statistically significant because the confidence interval approaches one. No other race was significantly different in terms of whether they were more or less likely to have seen an OB/GYN compared to White women. Type of insurance was not a significant factor. However, women without insurance were 77% less likely to visit an OB/GYN compared to those with private health insurance .p < 0:01/. Region of residence
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also played an important role in predicting this outcome, with women living in the Northeast the most likely to visit an OB/GYN, and women in the North Central/Midwest (OR D .53) and Western regions (OR D .54) the least likely to visit an OB/GYN. Women who were most likely to have visited an OB/GYN were those who have completed high school or master’s degrees or higher compared with women who have not completed high school. Women with higher levels of education may thus have better access to obstetric care, independent of other variables. There are several factors that limit the results of this study. First, this study is based on the results of a phone interview; all data were self-reported by those participating in the survey and were not confirmed via other methods. Recall bias or error may be present in this respect. Although the women included reported they were pregnant, the survey does not confirm their pregnancy status nor does it indicate a woman’s stage of pregnancy, her parity, or other information. This study also assumes that all women who are pregnant should have seen an OB/GYN in the past year and assumes that the factors affecting this decision are related to demographic factors and type of insurance. This study also does not take into account whether a pregnant woman intends to seek care from an OB/GYN, only if she has at the time of the survey. It also does not consider whether a woman has sought care from another primary care provider or another health provider, such as a general practitioner or a midwife. This study is also limited in the way it defines certain variables. For example, race includes the categories White, Black, Asian, American Indian, Native Alaskan, multiethnic group, or other. Whether a person is of Hispanic or Spanish origin is a separate variable. Nuances in these definitions may not accurately categorize individuals. Although Asian women seem to be at a higher risk for not receiving prenatal care in this analysis, Asian women represent a small number of this study population.
CONCLUSION This study suggests that race, health insurance, region of residence, and education level are all associated with access to obstetric care for pregnant women. This study provides evidence that pregnant women who have not completed high school, who are Asian, who do not have health insurance, and who live in the Midwest and West may be at the highest risk for not receiving prenatal care during pregnancy. In working to increase equality of access to care, especially for pregnant women, further targeted research in these areas may be necessary to determine appropriate interventions. Specifically, more research should be conducted to see what factors might make Asian women at a higher risk for not receiving prenatal care, especially because though this analysis suggests that Asian women are less likely to visit an OB/GYN, the National Healthcare Disparities Report shows that Asian/Pacific Islander women (and White women) are actually most likely to receive prenatal care (AHRQ, 2008). Although this study does not consider obstetric outcomes as a result of access to obstetric care, it nevertheless provides an important picture of which women are able to obtain obstetric care and which women may be at the highest risk for negative outcomes. Although this study also does not consider whether a woman will see an OB/GYN and if so, in what trimester, the results still suggest that some factors, especially a lack of health insurance, prevent women from receiving prenatal care. In addition to improving maternal and infant outcomes, prenatal care can improve overall maternal health, increase subsequent use of pediatric care, and may allow women at social or economic risk an entry point into the health care system (Rosenberg et al., 2007). Further targeted examination of these results is the next step in developing appropriate, targeted interventions to ultimately decrease disparities in maternal and infant outcomes.
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REFERENCES Agency for Healthcare Research and Quality. (2008). National healthcare disparities report 2007. Rockville, MD: Author. Bengiamin, M. I., Capitman, J. A., & Ruwe, M. B. (2010). Disparities in initiation and adherence to prenatal care: Impact of insurance, race-ethnicity and nativity. Maternal and Child Health Journal, 14, 618–664. Bryant, A. S., Worjoloh, A., Caughey, A. B., & Washington, A. E. (2010). Racial/ethnic disparities in obstetric outcomes and care: Prevalence and determinants. American Journal of Obstetrics and Gynecology, 335–343. Hughes, S., Zweifler, J. A., Garza, A., Stanich, & M. A. (2008). Trends in rural and urban deliveries and vaginal births: California 1998–2002. National Rural Health Association, 24(4), 416–422. Rosenberg, D., Handler, A., Rankin, K. M., Zimbeck, M., & Adams, E. K. (2007). Prenatal care initiation among very low-income women in the aftermath of welfare reform: Does pre-pregnancy Medicaid coverage make a difference? Maternal and Child Health Journal, 11, 11–17. Taylor, C. R., Alexander, G. R., & Hepworth, J. T. (2005). Clustering of U.S. women receiving no prenatal care: Differences in pregnancy outcomes and implications for targeting interventions. Maternal and Child Health Journal, 9(2), 125–133.
