Do birth control pills make acne better or worse?

A recent Cochrane review, a review of all the scientific studies, showed that birth control pills reduce acne. Although a few brands actually have FDA approval be labelled as reducing acne, the Cochrane review found all types of birth control pills to be equally effective.

The way birth control pills reduce acne is two fold. They decrease the amount of testosterone produced by the ovaries. They also increase production a substance called Sex Hormone Binding Globuin (SHBG) from the liver. The net result is a decrease in free or biologically active testosterone by about 50%. This reduces acne but the effect is somewhat subtle. Most women notice improvement after several months of using birth control pills.