If you’ve ever been on or even thought about going on some form of birth control, the question, “Will this make me gain weight?” has probably passed through your head. Weight gain is a common complaint and concern for many patients, says Mary Jane Minkin, M.D., a board-certified ob-gyn and a clinical professor at Yale University School of Medicine. (Kick-start your new, healthy routine with Women’s Health’s 12-Week Total-Body Transformation!)
The problem is that, for the most part, the reason why hormonal birth control might make you gain weight is a mystery, says Minkin. The pill, the ring, the patch, IUDs, and the shot can have vastly different side effects on women because we all have different hormone levels—for instance, you may have more naturally-occurring estrogen in your system than your BFF. And, unfortunately, the only way to know how a particular brand will affect you is to give it a try. So you’re essentially playing Russian roulette with your B.C.
But it’s not completely hopeless. The first step to determine whether or not your birth control will wreak havoc on your waistline is to find out which hormones it contains, says Minkin. When women gain weight on the pill, patch, or vaginal ring, which contain estrogen as the main baby-fighting ingredient, they’re most likely putting on water weight, says Minkin. That’s because estrogen can cause fluid retention, she says. The good news is that you’ll most likely be peeing out the excess weight at the end of each cycle when you’re off the pill for a few days, she says. Keep in mind this water-weight fluctuation could be up to 10 pounds.
Even if you can count on losing up to 10 pounds once a month, a weight fluctuation like that (obviously) isn’t ideal. The best way to avoid gaining water weight is to choose a birth control pill that contains drospirenone as the progestin component, like Yaz, Yasmin, and their generics, says Minkin. Typically, these don’t lead to weight gain because drospirenone acts as a diuretic, keeping you from retaining water. “Women don’t usually complain of bloating on these pills,” says Minkin. Unfortunately, only the pill contains drospirenone, according to the FDA.