Common Questions
How does current use of DMPA affect fracture risk in adolescents?
There are no published randomized controlled trials linking adolescent DMPA use with increased risk of fracture. Absolute fracture risk is very low during the premenopausal years and therefore it is difficult to design studies that are powered to detect fracture risk differences.
The only study of DMPA use and risk of fracture was a longitudinal investigation of 3,758 female US army recruits (1). The mean age was 21 and there were 169 DMPA users and 2,629 non-hormonal users. Quantitative ultrasound was used to measure bone density at the heel. The women were followed for eight weeks of basic training for occurrence of stress fracture. A total of 504 stress fractures occurred in 319 soldiers for an incidence of 8.5% per eight weeks. DMPA use was not a statistically significant risk factor for stress fracture when adjusted for bone density at baseline.
The women who developed stress fractures were more likely to report current or past history of smoking, greater then 10 alcoholic drinks per week, corticosteroid use, and lower adult weight as compared to those without fractures. Until randomized control trials are conducted there will continue to be insufficient data to assess whether DMPA use in adolescence affects fracture risk. However, since it appears that the effect of DMPA on bone mineral density (in adolescents) is largely reversible, any lifetime increase in fracture risk will likely be small.
- Lappe JM, Stegman MR, Recker RR. The impact of lifestyle factors on stress fractures in female Army recruits. Osteoporos Int 2001; 12: 35-42.