title: Body weight does not impact pregnancy rates during use of a low-dose extended-regimen 91-day oral contraceptive.
abstract: BACKGROUND
  This study evaluated the impact of weight on efficacy during use of an extended oral contraceptive (OC).
  
  
  METHODS
  Data were from a Phase 3 clinical trial evaluating the efficacy of a low-dose 91-day extended regimen of 100 mcg levonorgestrel/20 mcg ethinyl estradiol (LNG/EE; 84 days)+10 mcg EE (7 days) for the prevention of pregnancy. Crude pregnancy rates were calculated for weight and body mass index (BMI) deciles.
  
  
  RESULTS
  Of the 1736 women in this analysis, 878 (50.6%) had a BMI greater than 25 kg/m2, and 770 (44.4%) were heavier than 70 kg. Pregnancies occurred in 36 women. Crude pregnancy rates were similar across weight and BMI deciles, with no discernable differences observed between deciles using either classification criterion.
  
  
  CONCLUSIONS
  No evidence of any reduction in the level of contraceptive efficacy was observed with this low-dose extended OC regimen in overweight and obese women.
authors: Columbia University Medical Center, New York, NY 10032, USA.
authors: Carolyn L
authors: CL
authors: Westhoff
authors: Howard I
authors: HI
authors: Hait
authors: Kathleen Z
authors: KZ
authors: Reape
mesh_terms: D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D001835:Body Weight; D003278:Contraceptives, Oral, Hormonal; D004997:Ethinyl Estradiol / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D016912:Levonorgestrel / Q000008:administration & dosage*; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D003278:Contraceptives, Oral, Hormonal; D004997:Ethinyl Estradiol; D016912:Levonorgestrel