Maternal anthropometric factors and risk of primary cesarean delivery.
OBJECTIVE
This study examined absolute and proportional gestational weight gain and prepregnancy body mass index as predictors of primary cesarean delivery.


METHODS
Data were derived from a prospective study of pregnancy outcome risk factors in 2301 women in greater New Haven, Conn, who had singleton deliveries by primary cesarean (n = 312) or vaginal delivery (n = 1989) and for whom height, prepregnancy weight, and weight gain were available. Women were divided into 4 body mass index groups (underweight, low average, high average, and obese) and further subdivided into 8 groups according to median proportional or absolute weight gain.


RESULTS
Risk of cesarean delivery increased with increasing body mass index and gestational weight gain greater than the median for one's body mass index. Proportional weight gain was more predictive of cesarean delivery than absolute weight gain. Underweight women gaining more than 27.8% of their prepregnancy weight had a 2-fold adjusted relative risk of cesarean delivery.


CONCLUSIONS
Proportional weight gain is an important predictor of cesarean delivery for underweight women; high body mass index is also predictive of increased risk.
Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Conn. 06520-8034, USA.
M J
MJ
Shepard
A F
AF
Saftlas
L
L
Leo-Summers
M B
MB
Bracken
D000328:Adult; D001827:Body Height; D015992:Body Mass Index; D002585:Cesarean Section / Q000706:statistics & numerical data*; D003237:Connecticut; D005260:Female; D006801:Humans; D016015:Logistic Models; D011237:Predictive Value of Tests; D011247:Pregnancy; D011248:Pregnancy Complications; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking; D012959:Socioeconomic Factors; D015430:Weight Gain