title: Body mass index and operative times at cesarean delivery.
abstract: OBJECTIVE
  To examine the relationship between body mass index (BMI, kg/m) and incision-to-delivery interval and total operative time at cesarean delivery.
  
  
  METHODS
  Women with singleton gestations undergoing uncomplicated primary and repeat cesarean deliveries were identified from the Maternal-Fetal Medicine Units Network Cesarean Registry. Women were classified by BMI category at time of delivery (normal 18.5-24.9, overweight 25.0-29.9, obese 30.0-39.9, and morbidly obese 40 or greater). Incision-to-delivery interval and total operative times during cesarean delivery were compared among the three groups. Primary outcome was prolonged incision-to-delivery interval as defined by 90th percentile or greater of the study population or 18 minutes or longer.
  
  
  RESULTS
  Of the 21,372 women included in the analysis, 9,928 were obese (46.5%) and 2,988 (14.0%) were morbidly obese. Longer operative times were found among women with overweight (median [interquartile range] incision-to-delivery: 9.0 [6.0] and total operative time: 45.0 [21.0] minutes), obese (10.0 [7.0]; 48.0 [22.0] minutes), and morbidly obese BMIs (12.0 [8.0]; 55.0 [26.0] minutes) compared with women with normal BMI at delivery (9.0 [5.0]; 43.0 [20.0] minutes) (P<.001). Morbidly obese women had a more frequent incision-to-delivery interval that was 18 minutes or longer (n=602 [20%] compared with 127 [6%] in normal BMI). After adjustments including number of prior cesarean deliveries, incision-to-delivery interval 18 minutes or longer was significantly related to obese (odds ratio [OR] 1.62, 95% confidence interval [CI] 1.31-2.03) and morbidly obese (OR 2.81, 95% CI 2.24-3.56) BMI at delivery.
  
  
  CONCLUSIONS
  Increasing BMI is related to increased incision-to-delivery interval and total operative time at cesarean delivery with morbidly obese BMI exposing women to the highest risk of prolonged incision-to-delivery interval.
  
  
  METHODS
  : II.
authors.affiliation: Department of Obstetrics and Gynecology, Lucile Packard Children's Hospital at Stanford University, Stanford, and the Department of Obstetrics and Gynecology, Santa Clara Valley Medical Center, San Jose, California.
authors.forename: Anna I
authors.initials: AI
authors.lastname: Girsen
authors.forename: Sarah S
authors.initials: SS
authors.lastname: Osmundson
authors.forename: Mariam
authors.initials: M
authors.lastname: Naqvi
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Garabedian
authors.forename: Deirdre J
authors.initials: DJ
authors.lastname: Lyell
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002140:California; D002585:Cesarean Section / Q000009:adverse effects / Q000379:methods*; D017604:Cesarean Section, Repeat / Q000009:adverse effects / Q000379:methods; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D009765:Obesity / Q000150:complications*; D009767:Obesity, Morbid / Q000150:complications; D061646:Operative Time; D011247:Pregnancy; D011256:Pregnancy Outcome; D012042:Registries; D018570:Risk Assessment; D016896:Treatment Outcome