Follow me on

Birth Control And Obesity

sharma-obesity-birth-control-pillAlthough obesity is a well-recognised factor for female infertility, the vast majority of women with excess weight are probably more interested in effective birth control.

That this is not as simple as it seems is evident from an article by Sheila Mody and Michelle Han from the University of California, San Diego, published in Clinical Obstetrics and Gynecaology.

The paper succinctly reviews a wide range of issues related to birth control and obesity.

To begin with, the authors points out that unintended pregnancies in obese women are often a problem simply because obese women are far less likely to use effective contraception than non-obese women. This non-use may in part be attributable to fear of weight gain, when most studies show that modern hormonal contraception is associated with almost no weight gain. The exception appears to be depot-medroxyprogesterone (DMPA), which may cause about 5 lb weight gain in the first year of use.

As for efficacy, the data show that unintended pregnancy rates among overweight women using oral contraceptives are similar or slightly higher than that among nonoverweight women. The reasons for these higher rates are not exactly clear.

Fortunately, the efficacy of intrauterine devices (IUD) appear no different between obese and non-obese women although the insertion of an IUD maybe more difficult in obese women because of poor visualization of the cervix and limited assessment of uterine position (a problem that can often be solved with the help of an ultrasound).

The paper also discusses the suitability of the vaginal vaginal contraceptive ring, which has been hypothesized to offer higher hormone levels for obese women than oral contraceptives because the hormones are absorbed directly into the vaginal mucosa and do not go through the first- pass liver metabolism.

Finally, the paper discusses issues around contraception for women who have undergone bariatric surgery (who have a particularly high rate of unintended pregnancies) as well as best practices for emergency contraception.

This is clearly information that all clinicians who counsel obese women should be aware of.

Edmonton, AB

ResearchBlogging.orgMody SK, & Han M (2014). Obesity and Contraception. Clinical obstetrics and gynecology PMID: 25029338





  1. Interesting correlation. Thanks for posting this information.
    Are there case studies on brand name oral birth control, and pattern of weight gain?

    Post a Reply
  2. I gained 30 lbs in a year taking oral medroxyprogesterone acetate 5mg a day for endometriosis. From what I was able to gather researching the medical literature regarding depot med for birth control (there is not much about its use for endometriosis re:weight gain), it can have a very significant effect on weight. The average gain figures includes about 25% of women who lose 3-4 kgs, 50% who stay about the same weight, and 25% who gain significant amounts. It also affects body composition because it causes a loss in bone mass, and all the weight gained is basically fat. You don’t gain lean tissue with it as you would in normal weight gain, and the ratio of visceral to subcutaneous fat also increases. The women most likely to gain too much weight are those in the normal or overweight bmi categories. I was in the OW category when I started it, and am now in the obese category for bmi.

    Anyway, I stopped taking the pills and gaining weight six months ago, but I am finding it much harder than expected to lose anything, especially considering my weight now. I think it is because of those body composition changes.

    Post a Reply

Submit a Comment

Your email address will not be published. Required fields are marked *