Medroxyprogesterone acetate (Depo-Provera) and bone mineral density loss

Medroxyprogesterone acetate decreases serum estrogen levels, which can lead to bone mineral density loss. In an unpublished study involving women above the age of 18 who used the drug for up to 5 years, bone mineral density in the spine and hip was reduced by 5% to 6% below baseline.2 In contrast, women in the control group, who were not using hormonal contraception, had no significant change in bone mineral density. Loss of density was greatest in the first 2 years of use. Two years after stopping the drug, bone mineral density was only partially recovered. Preliminary results from an ongoing open-label self-selected nonrandomized group of adolescent women aged 12-18 years showed a similar decrease in bone mineral density of 4%-6.9% after 4.6 years of study.2 This decline was not seen in a group of unmatched adolescents not receiving the drug. It is unknown whether use of medroxyprogesterone acetate will lead to osteoporotic fractures later in life.