DMPA use by adolescents. (Clinical Challenges).

A 17-year-old, sexually active student wants a contraceptive that is discreet and convenient. After counseling, she chooses the progestin-only injectable depot-medroxyprogesterone acetate (DMPA). The method appeals to her because it is highly effective and requires only four clinic visits each year. But will DMPA be appropriate for this young client?

Women younger than 18 years can safely use DMPA, as the advantages of using the method generally outweigh the risks, according to the World Health Organization's medical eligibility criteria. However, bone demineralization occurs in DMPA users, especially those younger than 21 years. (3) Extent of bone loss in the spine and proximal femur depends upon the duration of use, with bone loss occurring as early as the first three months of use and becoming magnified by 15 years of use and longer. (4) Biochemical studies of bone resorption and formation have confirmed an association between DMPA use and bone loss. (5) A marked increase in bone density, especially at the spine, occurs following discontinuation, (6) but complete recovery may not occur in all bones. The adolescent years are the time of maximum bone deposition, and impairment of mineral deposition during this interval may have long-lasting effects. The concern is that women who have used DMPA as adolescents may enter menopause with a bone deficit and thus be more likely to suffer fractures than those who have not used the contraceptive method.

However, DMPA has several advantages for teenagers. Its use is discreet. Also, it offers long-term pregnancy protection, convenience, high effectiveness, and low cost. (7) The disadvantages of unplanned adolescent pregnancy probably outweigh the potential risk of bone loss. This client should be told, however, that DMPA will not protect her from sexually transmitted infections (STIs). If she is at risk for STIs/HIV, she should consistently use--in addition to DMPA--a condom for STI protection.

(3.) Scholes D, LaCroix AZ, Ott SM, et al. Bone mineral density in women using depot medroxyprogesterone acetate for contraception. Obstet Gynecol 1999;93(2):233-38; Cundy T, Cornish J, Roberts H, et al. Spinal bone density in women using depot medroxyprogesterone contraception. Obstet Gynecol 1998;92(4 Pt 1):569-73; Cromer BA, Blair JM, Mahan JD, et al. A prospective comparison of bone density in adolescent girls receiving depot medroxyprogesterone acetate (Depo-Provera), levonorgestrel (Norplant), or oral contraceptives. J Pediatr 1996; 129(5):671-76.

(4.) Scholes; Cundy.

(5.) Ott SM, Scholes D, LaCroix AZ, et al. Effects of contraceptive use on bone biochemical markers in young women. J Clin Endocrinol Metab 2001;86(1):179-85.

(6.) Scholes D, LaCroix AZ, Ichikawa LE, et al. Injectable hormone contraception and bone density: results from a prospective study. Epidemiology 2002;13(5):581-87.

(7.) Davis AJ. Use of depot medroxyprogesterone acetate contraception in adolescents. J Reprod Med 1996;41(5 Suppl):407-13.