Unveiled almost 50 years ago, “the pill” continues to be the most popular and one of the most effective forms of reversible birth control ever invented. Since their introduction in 1960, oral contraceptives  have been changed to include less hormones, resulting in fewer side effects. Today’s OCs even provide health benefits. Studies show that the incidence of ovarian cancer, endometrial cancers, benign cysts of the ovaries and breasts and pelvic inflammatory disease   decreases with pill use. OCs also reduce the odds of getting colorectal cancer. But despite these advantages, young women who are trying to build muscle mass may want to choose another form of contraception.Researchers from the Department of Health and Kinesiology at Texas A&M University in College Station, as well as the Human Energy Research Laboratory at the University of Pittsburgh, have found that OCs actually limit muscle gain from strength training in women under 35. The research involved 73 relatively healthy women aged 18 to 31. Of these, 34 used OCs and 39 did not. Both groups participated in a whole-body resistance exercise program consisting of 13 exercises performed three times per week for 10 weeks. At each session, they completed three sets of six to 10 repetitions of each exercise at 75 percent of maximum strength. The women were encouraged to eat enough protein to promote muscle growth.