title: Effect of obesity on length of labor in nulliparous women.
abstract: We compared the duration of labor among nulliparous women with varying body mass index (BMI). Laboring nulliparous women at >37 weeks were included. First visit BMI was used to categorize weight as normal (≤24), overweight (25 to 29.9), or obese (≥30 kg/m(2)). Chi-square, one-way analysis of variance, and Bonferroni multiple comparisons tests were used. During 15 months, 375 women met the inclusion criteria, and 38% were obese. Duration of first stage of labor was significantly longer for obese versus normal-weight women (26.76 ± 0.77 versus 23.87 ± 0.66 hours; p = 0.024) but not between normal versus overweight women (p = 1.00) or overweight versus obese women (p = 0.114). The cesarean delivery rate was significantly different in the three groups (p = 0.0001), highest among obese (47%) and lowest in normal-weight women (24%). When adjusted for age, hypertension, and induction, the likelihood of completing stage I was significantly less among obese nulliparous than those with BMI < 24 kg/m(2) (hazard ratio 0.73, 95% confidence intervals 0.54, 0.99). Compared with those with BMI < 24, the duration of stage I is significantly longer among obese women, even when adjusted for maternal age, induction, and hypertension.
authors: Department of Obstetrics and Gynecology, Eastern Virginia Medical School, Norfolk, Virginia 23507, USA.
authors: Allyson M
authors: AM
authors: Hilliard
authors: Suneet P
authors: SP
authors: Chauhan
authors: Yueqin
authors: Y
authors: Zhao
authors: Nicole C
authors: NC
authors: Rankins
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002585:Cesarean Section / Q000706:statistics & numerical data*; D036861:Delivery, Obstetric / Q000379:methods; D005260:Female; D006801:Humans; D046110:Hypertension, Pregnancy-Induced / Q000453:epidemiology; D007231:Infant, Newborn; D007745:Labor Onset; D007751:Labor, Induced / Q000706:statistics & numerical data; D009765:Obesity / Q000453:epidemiology*; D011225:Pre-Eclampsia / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology*; D011256:Pregnancy Outcome / Q000453:epidemiology*; D013997:Time Factors; D055815:Young Adult