Original Paper Gynecol Obstet Invest 1992;34:79-81
Department of Gynecology and Obstetrics, Skive Hospital, Skive, Denmark
Keyw ords
Low body mass index Constitutional low weight for height Labor complications
Prepregnancy Low Body Mass Index Is Not a Predictor of Labor Complications
Abstract
The course of delivery and fetal outcome in 149 women with forecoming normal pregnancy and a prepregnancy body mass index (BMI) less than 20.0 were compared to a similar group of women with BMI between 20.0 and 24.9 after matching for age and parity. None of the women was undernourished. Sus pected intrauterine asphyxia was significantly more common in primipara with BMI below 18.0 than in their controls (6/12 vs. 1/12), and there was a trend towards fewer babies weighing at least 4,000 g in the women with low BMI. No other significant differences related to BMI were found. It is con cluded, that constitutional low weight for height is not a predictor of complica tions during delivery, and no special observation of this group is recom mended.
While undernourishment is extremely rare among fer tile, Danish women, low body mass index (BMI) as the expression of constitutional low weight for height is rela tively common. In the literature, little attention has been given to the obstetric course of this group of women, although maternal low weight seems to be associated with some adverse outcome of pregnancy, i.e. premature labor [1,2] and increased risk of uterine bleeding during preg nancy [3], To the best of our knowledge, the effect of con stitutional low BMI on labor itself has never been investi gated. The purpose of the present study was to compare the course of labor and fetal outcome in a group of women with low BMI not caused by undernourishment with the outcome in a group of women with normal BMI. Thereby, we wanted to show the effect of low BMI per se on labor.
Received: July 23,1991 Accepted: January 31, 1992
Material and Methods Constitutional low weight for height was defined as a prepreg nancy BMI below 20.0. A BMI below 18.0 was regarded as very low. The normal range of BMI was between 20.0 and 24.9. At Skive Hospital, prepregnancy weight and height are standard informations for the obstetric records. All records of women seen for the first antenatal visit during the period from 1st June 1987 to 31 st May 1989 were reviewed and BMI calculated. If the pregnancy was registered as normal and BMI was below 20.0, the woman was included in the investigation. Women with coincident medical dis ease, drug addiction, twins or breech presentation were excluded. Women seen during the same period with a BMI between 20.0 and 24.9 served as controls. After matching for age ( ± 1 year) and parity (1. para, 2.-3. para, > 4. para), the controls were randomly drawn from the central registry of patients. In both groups we registered the course of labor, individual kind of complications, operative deliveries, oxytocin stimulation, and the outcome of pregnancy expressed as the incidence of birthweights below 2,500 g, birthweights above 4,000 g and Apgar scores of 7/1 or less. As statistic test, x2-tcst or Fischer’s exact test was used. The limit of significance was 5%.
Dr. K. Rasmussen Glacnsovej 10 Skovsborg DK-8620 Kjellerup (Denmark)
© 1992 S. Karger AG. Basel 0378-7346/92/0342-0079 $2.75/0
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/6/2018 10:08:58 PM
Kjeld Leisgaard Rasmussen Kirsten Borup
Table 1. The course of labor in relation to BMI and parity
Results
Multipara
low BMI controls
low BMI controls
No complications Complications
25 27
27 25
81 16
75 22
Total
52
52
97
97
Table 2. Individual kinds of registered complications
Primary inertia Secondary inertia PROM Atonia Suspected asphyxia Blood loss > 500 cm3 Other
Low BMI
Controls
n
%
n
%
10 17 4 5 12 9 4
7 11 3 3 8 6 3
8 16 8 7 9 11 7
5 11 5 5 6' 7 5
More than one registration per patient. PROM - Premature rup ture of the membranes. 1 See text.
Table 3. Oxytocin stimulation and operative delivery
Oxytocin infusion Vacuum extraction Cesarean section Other
Low BMI
Controls
n
%
n
%
31 19 5 5
21 13 3 3
29 12 7 6
19 8 5 4
More than one registration per patient.
Table 4. Children with extreme birth weight or low Apgar score
Birth weight < 2,500 g Birth weight > 4,000 g Apgar score
Department of Gynecology and Obstetrics, Skive Hospital, Skive, Denmark
Keyw ords
Low body mass index Constitutional low weight for height Labor complications
Prepregnancy Low Body Mass Index Is Not a Predictor of Labor Complications
Abstract
The course of delivery and fetal outcome in 149 women with forecoming normal pregnancy and a prepregnancy body mass index (BMI) less than 20.0 were compared to a similar group of women with BMI between 20.0 and 24.9 after matching for age and parity. None of the women was undernourished. Sus pected intrauterine asphyxia was significantly more common in primipara with BMI below 18.0 than in their controls (6/12 vs. 1/12), and there was a trend towards fewer babies weighing at least 4,000 g in the women with low BMI. No other significant differences related to BMI were found. It is con cluded, that constitutional low weight for height is not a predictor of complica tions during delivery, and no special observation of this group is recom mended.
While undernourishment is extremely rare among fer tile, Danish women, low body mass index (BMI) as the expression of constitutional low weight for height is rela tively common. In the literature, little attention has been given to the obstetric course of this group of women, although maternal low weight seems to be associated with some adverse outcome of pregnancy, i.e. premature labor [1,2] and increased risk of uterine bleeding during preg nancy [3], To the best of our knowledge, the effect of con stitutional low BMI on labor itself has never been investi gated. The purpose of the present study was to compare the course of labor and fetal outcome in a group of women with low BMI not caused by undernourishment with the outcome in a group of women with normal BMI. Thereby, we wanted to show the effect of low BMI per se on labor.
Received: July 23,1991 Accepted: January 31, 1992
Material and Methods Constitutional low weight for height was defined as a prepreg nancy BMI below 20.0. A BMI below 18.0 was regarded as very low. The normal range of BMI was between 20.0 and 24.9. At Skive Hospital, prepregnancy weight and height are standard informations for the obstetric records. All records of women seen for the first antenatal visit during the period from 1st June 1987 to 31 st May 1989 were reviewed and BMI calculated. If the pregnancy was registered as normal and BMI was below 20.0, the woman was included in the investigation. Women with coincident medical dis ease, drug addiction, twins or breech presentation were excluded. Women seen during the same period with a BMI between 20.0 and 24.9 served as controls. After matching for age ( ± 1 year) and parity (1. para, 2.-3. para, > 4. para), the controls were randomly drawn from the central registry of patients. In both groups we registered the course of labor, individual kind of complications, operative deliveries, oxytocin stimulation, and the outcome of pregnancy expressed as the incidence of birthweights below 2,500 g, birthweights above 4,000 g and Apgar scores of 7/1 or less. As statistic test, x2-tcst or Fischer’s exact test was used. The limit of significance was 5%.
Dr. K. Rasmussen Glacnsovej 10 Skovsborg DK-8620 Kjellerup (Denmark)
© 1992 S. Karger AG. Basel 0378-7346/92/0342-0079 $2.75/0
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/6/2018 10:08:58 PM
Kjeld Leisgaard Rasmussen Kirsten Borup
Table 1. The course of labor in relation to BMI and parity
Results
Multipara
low BMI controls
low BMI controls
No complications Complications
25 27
27 25
81 16
75 22
Total
52
52
97
97
Table 2. Individual kinds of registered complications
Primary inertia Secondary inertia PROM Atonia Suspected asphyxia Blood loss > 500 cm3 Other
Low BMI
Controls
n
%
n
%
10 17 4 5 12 9 4
7 11 3 3 8 6 3
8 16 8 7 9 11 7
5 11 5 5 6' 7 5
More than one registration per patient. PROM - Premature rup ture of the membranes. 1 See text.
Table 3. Oxytocin stimulation and operative delivery
Oxytocin infusion Vacuum extraction Cesarean section Other
Low BMI
Controls
n
%
n
%
31 19 5 5
21 13 3 3
29 12 7 6
19 8 5 4
More than one registration per patient.
Table 4. Children with extreme birth weight or low Apgar score
Birth weight < 2,500 g Birth weight > 4,000 g Apgar score
