title: Etonorgestrel concentrations in morbidly obese women following Roux-en-Y gastric bypass surgery: three case reports.
abstract: BACKGROUND
  Pregnancy should be avoided for 12 to 18 months after Roux-en-Y gastric bypass (RYGB) surgery. The etonorgestrel (ENG)-releasing implant (Implanon®) may represent a safe and effective contraceptive method in morbidly obese women who are candidates for bariatric surgery. In addition, the subcutaneous delivery of steroid is unaffected by malabsorptive surgery.
  
  
  METHODS
  Three cases of young women with ENG-releasing implant are reported. The device was inserted 1-2 months prior to RYGB.
  
  
  RESULTS
  Their initial weights were 130 to 176 kg, and the mean weight loss was 33.6 kg at 6 months. The concomitant serum ENG concentrations decreased currently with weight loss but remained above the minimum concentration required for effective contraceptive effect of the implant for at least 6 months following RYGB (average, 170 pg/mL). The concentrations observed before weight loss were lower than in normal-weight women, but decreases in ENG concentrations following implant insertion were similar.
  
  
  CONCLUSIONS
  These unique data in morbidly obese women highlight the need for further pharmacokinetic studies of contraceptive agents in obese women during weight loss.
authors.affiliation: Department of Nutrition, Pitié-Salpêtrière Hospital (AP-HP), University Pierre et Marie Curie-Paris 6, 75013 Paris, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Ciangura
authors.forename: Nicola
authors.initials: N
authors.lastname: Corigliano
authors.forename: Arnaud
authors.initials: A
authors.lastname: Basdevant
authors.forename: Stéphane
authors.initials: S
authors.lastname: Mouly
authors.forename: Xavier
authors.initials: X
authors.lastname: Declèves
authors.forename: Philippe
authors.initials: P
authors.lastname: Touraine
authors.forename: Celia
authors.initials: C
authors.lastname: Lloret-Linares
mesh_terms: D000327:Adsorption; D000328:Adult; D015992:Body Mass Index; D003271:Contraceptive Agents, Female / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D017135:Desogestrel / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D004343:Drug Implants; D005260:Female; D015390:Gastric Bypass; D006801:Humans; D009767:Obesity, Morbid / Q000097:blood* / Q000601:surgery*; D015431:Weight Loss; D055815:Young Adult
chemical_list: D003271:Contraceptive Agents, Female; D004343:Drug Implants; C044815:etonogestrel; D017135:Desogestrel