What are disadvantages of injectable DMPA for contraception?

Updated: Oct 16, 2019
  • Author: Frances E Casey, MD, MPH; Chief Editor: Richard Scott Lucidi, MD, FACOG  more...
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Disruption of the menstrual cycle to eventual amenorrhea occurs in 50% of women within the first year. Persistent irregular bleeding can be treated by administering the subsequent dose earlier or by prescribing temporary low-dose estrogen therapy. Because DMPA persists in the body for several months in women who have used it on a long-term basis, it can delay the return to fertility. Approximately 70% of former users desiring pregnancy conceive within 12 months, and 90% of former users conceive within 24 months. Similar to the delay in fertility after discontinuation of DMPA, other adverse effects, such as weight gain, depression, and menstrual irregularities, may continue for as long as 1 year after the last injection.

A study by Bonny and colleagues found that adolescent girls, who gained more than 5% of their baseline weight after 6 months of DMPA use, are at an increased risk for excessive future weight gain. They concluded that weight gain after 6 months can be used to identify those at risk for further weight gain. Counseling can then be instituted for these patients. [5]

The FDA issued a "black-box" warning in November 2004, stating that bone loss from using Depo-Provera "may not be completely reversible" even after stopping the drug. The warning urged women not to use Depo-Provera on a long-term basis unless all other methods were inadequate.

Most users of DMPA are teens at a crucial age for the building of bone density; about 10% of American females aged 15-19 years who use birth control use Depo-Provera, compared with 3% of women in the United States overall.

Studies have contradicted the FDA warning. Women who stopped using DMPA experienced an average bone gain of 1.34% at the hip versus a loss of 0.19% for women who never took the drug. Spine density increased 2.86% for women who stopped using the drug, compared with an increase of 1.32% for nonusers. Furthermore, teens regained their bone density faster than older women using Depo-Provera. [6]

The main limitation, from the patient's point of view, has been the intramuscular (IM) route of injection, which requires an office visit every 12-14 weeks for administration. A subcutaneous version of the drug is now available (depo-subQ provera 104) that delivers a lower dose of medroxyprogesterone acetate (MPA) than does the intramuscular formulation (104 mg vs 150 mg). The subcutaneous route opens the possibility for home self-injections, and the lower dose could decrease suppression of pituitary function and ovarian estradiol production. Further study is needed.

Subcutaneous DMPA, like its intramuscular counterpart, is associated with changes in bone mineral density and also carries a "black box" warning regarding this risk. Studies demonstrate lower decreases in bone mineral density as compared with the intramuscular route and the same reversible effect. [7]


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