Clarification of contraceptive drug pharmacokinetics in obesity

Contraception. 2017 Jan;95(1):10-16. doi: 10.1016/j.contraception.2016.08.003. Epub 2016 Aug 16.


Related to concerns about the role of obesity in the efficacy of contraceptive drugs, a review of the literature was carried out in regard to the pharmacokinetics of ethinyl estradiol and various progestins given by various routes of administration. Most studies show that obese women exhibit modestly lower plasma concentrations of these drugs (circa 30%) when given the same doses as normal-weight women. While the mechanism is uncertain, precedence in the literature suggests that this is due to body weight-related differences in metabolism rates. Confusing in some of the literature is that a few studies have reported erroneously calculated pharmacokinetic parameters after multiple dosing of oral contraceptives. A demonstration of appropriate pharmacokinetic methodology is provided.

Keywords: Clearance; Contraceptive drugs; Model-fitting; Obesity; Pharmacokinetics; Volume of distribution.

Publication types

  • Review
  • Research Support, N.I.H., Extramural

MeSH terms

  • Body Weight
  • Contraceptives, Oral / pharmacokinetics*
  • Ethinyl Estradiol / pharmacokinetics
  • Female
  • Humans
  • Levonorgestrel / pharmacokinetics
  • Obesity / blood*
  • Obesity / physiopathology


  • Contraceptives, Oral
  • Ethinyl Estradiol
  • Levonorgestrel