NEW YORK (Reuters Health) – The potential bone loss that may occur with depot medroxyprogesterone acetate (DMPA), a long-acting, injectable contraceptive introduced in 1992, should not deter doctors from prescribing the agent when it seems appropriate, according to a Committee Opinion issued by the American College of Obstetrics and Gynecology.

The recommendation is published in the journal Obstetrics & Gynecology. Dr. Denise Jamieson, chair of ACOG’s Committee on Gynecologic Practice, and colleagues point out that “increased use of DMPA in the past 15 years has been paralleled by a decrease in the adolescent pregnancy rate. Although there are many factors contributing to the decrease in adolescent pregnancies, DMPA has likely played a role.”

The Committee notes that while DMPA increases bone breakdown, with a resultant loss in bone thickness, this risk must be weighed against the benefits of the high pregnancy-prevention rate — especially in light of the fact that bone thickness returns after DMPA has been stopped.

Women should be counseled about the risks associated with DMPA, the panel advises, and for those who elect to use it, daily age-appropriate calcium and vitamin D supplementation should be recommended. Women should also be told about the importance of regular exercise in maintaining bone health.

However, concerns about DMPA’s effect on bone thickness “should neither prevent practitioners from prescribing DMPA nor limit its use to 2 consecutive years,” Jamieson and colleagues write.

Bone thickness monitoring is not needed “solely in response to DMPA use,” they add, because any short-term bone loss is recoverable and probably won’t increase the current or future risk of fracture, they note.

SOURCE: Obstetrics and Gynecology, September 2008.