Depo-Provera and Bone Loss

Around two million women use Depo-Provera as their contraceptive of choice. About 400,000 of them are teenagers. Depo-Provera is popular with teenagers because of its ease of use – just a single injection is required every three months.

However, Depo-Provera has one side effect not shared by oral contraceptives; it causes a slight but statistically significant bone loss. Researchers compared bone mineral density in young women aged 12-18 who used either Depo-Provera, oral contraceptives, or no birth control at all (the control group) for two years. Bone mineral density increased over the two-year period in the control group, as expected in young women still in their teens. It also increased in the oral contraceptives group by the same amount. However, bone mineral density decreased slightly but significantly in the Depo-Provera group.

The decrease in bone mineral density among Depo-Provera users was not sufficient to pose an immediate health risk, and any long-term risks are still unknown. Nevertheless, women’s health experts suggest that teenagers who are taking Depo-Provera should be sure to get enough calcium in their diet.

Reference: Cromer, Barbara A., et al. Bone mineral density in adolescent females using injectable or oral contraceptives; a 24-month prospective study. Fertility and Sterility 90: 2060-2067, 2008.