How does current DMPA use affect bone mineral density (BMD) in adolescents?
DMPA use during adolescence is associated with decreased bone density in both the spine and the hip (1-2). The rate of bone loss appears to be greatest during the first year of use and may slow with longer use. There have been no randomized control trials looking at the effects on DMPA on bone loss in adolescents.
Four prospective, observational studies of adolescents, ages 11-21 years, compared BMD of those who received DMPA injections at 12-week intervals for up to two years versus non-users (3-7).
- BMD at the lumbar spine in users of DMPA decreased an average of -3.1% (range -1.5% to -6.0%) compared to an average of +7.2% (range +5.9% to +9.5%) in non- users.
- The total average discrepancy in the BMD between DMPA users and non-users was 10.3%.
- The BMD decreases were greater in the first year of DMPA use.
There are four longitudinal studies in adult women over the age of 18 comparing DMPA users and non-users. All of the studies reported a decrease in BMD among DMPA users compared to non-users. The loss to follow up in these studies was substantial (approx 60%) therefore the significance of these results is questionable. Mean changes in BMD were overall quite small. The rate of change of BMD ranged from 1-3% per year (7).
The FDA added a black box labeling to depot medroxyprogesterone acetate (DMPA) in 2004 to advise clinicians and users about the risk of bone loss in adolescents who use DMPA for prolonged periods of time (8). They emphasized that the loss of bone mineral density (BMD) may be greater the longer the drug is administered. In addition, they warned that the bone loss may not be completely reversible and it is unknown whether effects on BMD during peak times of bone growth in adolescents will increase their risk for osteoporotic fractures later in life. Currently, the FDA recommends that women only use DMPA as a long-term birth control method (for example longer than two years) if other birth control methods are inadequate or contraindicated. As a result, providers and users of DMPA are re-evaluating the risks and benefits of this convenient method of birth control.
- Scholes D, LaCroix AZ, Ichikawa LE, Barlow WE, Ott SM. The association between depot medroxyprogesterone acetate contraception and bone mineral density in adolescent women. Contraception 2004; 69: 99-104.
- Cundy T, Cornish J, Roberts H, Elder H, Reid IR. Spinal bone density in women using depot medroxyprogesterone acetate contracaception. Obstet Gynecol 1998; 92: 569-73.
- Cromer BA, Blair JM, Mahan JD, Zibners L, Naumovski Z. A prospective comparison of bone density in adolescent girls receiving depot medroxyprogeserone acetate (Depo-Provera), levonorgestrel (Norplant) or oral contraceptives. J Pediatr 1996; 129: 671-6.
- Lara-Torre E, Edwards CP, Perlman S, Hertweck SP. Bone mineral density in a cohort of adolescent women using depot medroxyprogesterone acetate. J Pediat Adolesc Gynecol 2004; 17: 17-21.
- Cromer BA, Stager M, Bonny A, et al. Depot medroxyprogesterone acetate, oral contraceptives and bone mineral density in a cohort of adolescent girls. J Adolesc Health 2004; 35: 434-41.
- Busen NH, Britt RB, Rianon N. Bone mineral density in a cohort of adolescent women using depot medroxyprogesterone acetate for one to two years. J Adolesc Health 2003; 32: 257-9.
- Curtis KM, Martins SL. Progestogen-only contraception and bone mineral density: a systematic review. Contraception 2006; 73: 470-487.
- D'Arcangues C. WHO statement on hormonal contraception and bone health. Contraception 2006; 73(5): 443-444.