The study tracked 703 women in two age groups age 16-24 and 25-33 using Depot medroxyprogesterone. However, researchers at the University of Texas Medical Branch in Galveston said women who switched to non-hormonal contraception began to slowly lose the weight and fat mass they gained -- nearly 4 pounds over two years, while those who used oral contraception after the shots gained an average of four additional pounds in the same time span. The amount of weight gain was dependent on the length of time depot medroxyprogesterone acetate, commonly known as the birth control shot, was used, as the rate of weight gain slo over time. Birth control shot linked to weight gain Women who get the birth control shot gained an average of 11 pounds and increased their body fat by 3.4 percent over three years, U.S. The study, published in the American Journal of Obstetrics and Gynecology, said depot medroxyprogesterone acetate is an injected contraceptive administered to patients every three months, which is used by some 2 million American women.

Women and their doctors should factor in this new data when choosing the most appropriate birth control method, lead Trumann Berenson said in a statement.