Weight Gain, Fluid Retention and the Pill
Frederick R. Jelovsek MD, MS
\\\"I have been taking birth control pills for about six months now. I am thrilled at the idea of not becoming pregnant, however, my problem is tremendous weight gain as a result of water retention. I have experienced no increased appetite, however my breasts are a full cup size larger and I feel that I have an added layer onto my body that makes me very uncomfortable. Is there anything that can be done about this problem?\\\" Anon
Before we know if there is any way we can treat weight gain associated with oral contraceptives, we need to know if birth control pills cause fluid retention and by what mechanism, do they cause increased appetite and how, and do they cause temporary or long term weight gain by those or any other mechanisms?
With studies of recent low dose oral contraceptives, the whole premise as to whether there is any change in weight at all with beginning oral contraceptives is in question (1). This and other studies indicate that, on the average, women do not gain weight because of the pills. Remember this means that if 5-10% of women report weight gain when starting oral contraceptives, there is an identical 5-10% of women who gain weight even though they did not get active birth control pills. In other words the weight gain with pills was coincidental but not a cause and effect.
We know from older birth control pill studies, however, that weight gain was a problem both from fluid retention and from more fat deposition so we need to look at what was learned from those studies because those factors may be active in some women who are sensitive to them even at today\\\'s low pill hormone doses.
Do most women gain weight when starting on oral contraceptives and if so how much?
For the most part, older studies using higher dose pills tend to show an average of about 5 lb weight gain using pills. One study looked at adolescents who were using DeproProvera® (DMPA) for contraception and compared them to other teens using birth control pills (1). They found that after one year of contraception, the average weight gain was 6.6 lbs (3.0 kg) in the adolescents using shots (DMPA) and 5.3 lbs (2.4 kg) when using oral contraceptives. More importantly, only 7% of pill users gained more than 10% of their body weight while 25% of the DepoProvera® users gained more than 10%. If you just look at the average weight gain of 6.6 lbs vs 5.3 lbs, you would conclude that DMPA had only a slightly higher weight gain than pills. The fact that these averages include 18% more woman who gained greater than 10% of body weight can be hidden by average weight changes. Thus DepoProvera® has a greater side effect of weight gain than oral contraceptives.