[Contraception and obesity]

The prevalence of obesity is increasing massively over several decades in industrialized countries. Obese women are sexually active but they use fewer contraceptive methods and are at high risk of unintended pregnancy. In addition, obesity is an important risk factor for venous thromboembolism events and arterial thrombosis (myocardial infarction and ischemic stroke). All of these data are to be considered in choosing a contraceptive method for obese women. Except depot medroxyprogesterone acetate injection, the progestin-only contraceptives (progestin only pills and etonogestrel subdermal implant) and the intra-uterine devices are the preferred contraceptive methods in obese women. The combined estrogen-progestin contraceptives (pill, patch and vaginal ring) may be proposed in very strict conditions (no other associated vascular risk factor). Obesity does not increase the risk of failure of most contraceptive methods. Bariatric surgery is a complex situation. It requires to program a possible pregnancy and contraception is needed for several months. Some bariatric surgical techniques such as by-pass can induce gastrointestinal malabsorption. In this situation, all oral contraceptives are not recommended because of a higher risk of failure.