Objective: We sought to compare labor patterns by body mass index (BMI). Study Design: A total of 118,978 gravidas with a singleton term cephalic gestation were studied. Repeated-measures analysis constructed mean labor curves by parity and BMI categories for those who reached 10 cm. Interval-censored regression analysis determined median traverse times, adjusting for covariates in vaginal deliveries and intrapartum cesareans. Results: In the labor curves, the time difference to reach 10 cm was 1.2 hours from the lowest to highest BMI category for nulliparas. Multiparas entered active phase by 6 cm, but reaching this point took longer for BMI <40.0 (3.4 hours) compared to BMI <25.0 (2.4 hours). Progression by centimeter (P <.001 for nulliparas) and from 4-10 cm (P <.001 for nulliparas and multiparas) increased as BMI increased. Second stage length, with and without an epidural, was similar among BMI categories for nulliparas (P >.05) but decreased as BMI increased for multiparas (P <.001). Conclusion: Labor proceeds more slowly as BMI increases, suggesting that labor management be altered to allow longer time for these differences.
|Original language||English (US)|
|Journal||American journal of obstetrics and gynecology|
|State||Published - Sep 2011|
- body mass index
- labor curves
ASJC Scopus subject areas
- Obstetrics and Gynecology