BMD loss prompts black box for Depo-Provera

OB/GYN News, Dec 15, 2004 by Heidi Splete

The U.S. Food and Drug Administration has added a black box warning to Depo-Provera to emphasize the potential for bone mineral density loss with long-term use of the injectable contraceptive.

Depo-Provera has been used throughout the world for decades and remains a safe and effective method of birth control, the FDA said in a statement. However, a recent review of the drug's long-term effects on bone mineral density (BMD) by the FDA and Pfizer Inc., which manufactures the drug, prompted the addition to the label.

The black box warning notes that women who use Depo-Provera may experience a significant decrease in BMD that might not be completely reversible after discontinuing use. Consequently, Depo-Provera should be used as a long-term birth control method (more than 2 years) only if other methods are inadequate.

The warning also states that it's not known whether Depo-Provera use during adolescence or early adulthood will reduce peak bone mass and increase the risk of osteoporotic fracture in later life.

Since the U.S. approval of Depo-Provera in 1992, the prescribing information has included a warning that use of the contraceptive may be considered among the risk factors for development of osteoporosis, Pfizer noted in a statement. Additional clinical research was initiated in the 1990s to clarify the effects of Depo-Provera on BMD. Results of those studies were considered in the review and led to the labeling revisions.

One of the studies included 540 women aged 25-38 years who used Depo-Provera for 5 years and were then followed for 2 years. The review also included data from an ongoing study of nearly 400 adolescents aged 12-18 years that will end in 2006 after 5 years of treatment and 2 years of follow-up, said Pfizer spokesperson Rebecca Hamm.

Physicians should encourage patients to consider other contraceptive options for long-term use, Ms. Hamm noted. If women choose to continue using Depo-Provera long-term, physicians should consider periodic BMD tests and advise these patients to take calcium supplements, quit smoking, and engage in moderate exercise to help prevent BMD loss, she said.

BY HEIDI SPLETE

Senior Writer