The effect of depot medroxyprogesterone acetate (DMPA) on bone mineral density (BMD) and evaluating changes in BMD after discontinuation of DMPA in Chinese women of reproductive age

Abstract

Background: Depot medroxyprogesterone acetate (DMPA) as a hormonal contraceptive is highly effective and widely used, but it may reduce bone mineral density (BMD) and increase the risk of osteoporosis. We compared BMD between users of intramuscular DMPA and nonhormonal subjects and evaluated the changes in BMD after discontinuation of DMPA.

Study design: The study included 68 women aged between 25 and 40 years using DMPA for 24 months and 59 women aged between 25 and 40 years using nonhormonal contraception as nonusers of hormonal contraception. Sixty-one women in the DMPA group and 52 women in the nonusers of hormonal contraception group completed the 2-year post-treatment periods. BMD of the lumbar spine and femoral neck was measured every 12 months for 48 months using dual-energy X-ray absorptiometry, comparing mean BMD changes in DMPA users and discontinuers with nonusers.

Results: At 24 months of treatment, as compared to baseline, the mean BMD of DMPA users in lumbar spine and femoral neck decreased by 5.52% and 6.35%, respectively. Lumbar spine and femoral neck BMD in women who used DMPA significantly decreased compared to the nonusers (p<.001). At 24 months after DMPA discontinuation, the mean BMD values in DMPA users increased significantly. Although the values of the lumbar spine and femoral neck BMD in DMPA users were still 1.08% and 2.30%, respectively, below their baseline values, there were no significant difference when compared to nonusers (p>.05).

Conclusion: These results show that BMD declined during use of DMPA in women aged 25 to 40 years. Bone loss occurring with DMPA use is reversible after DMPA discontinuation.