Maternal age and labor complications in healthy primigravidas at term.

The objective of this study was to describe the association between maternal age and selected risk indicators (both recognized and potential) to determine whether any were predictive of labor complications in women having a first child. Low-risk primigravidas (n = 1,792) were selected from a large national probability sample of births for 1988 (the National Maternal and Infant Health Survey). Recognized and potential risk indicators were described according to categories of maternal age and the occurrence of labor problems. Stratified analysis and logistic regression were used to assess the association of various risk factors with labor complications adjusted for maternal age. Only cesarean delivery varied significantly across maternal age groups, the rate being 11.6% for those < 20, 15.9% for those age 20-29, and 28.3% for those > or = 30. Cesarean delivery was associated with several characteristics of social advantage. Independent risk factors for cesarean delivery were maternal age (particularly > or = 30), epidural anesthesia, and receipt of adequate prenatal care. We conclude that older primigravidas have significantly more cesarean deliveries, and this is partially explained by characteristics of social advantage. To address the high cesarean rate, care providers need a better understanding of the relationship between social circumstances and cesarean delivery.