Progestin-only contraception prevents bone loss in postpartum breastfeeding women

Contraception. 2012 Apr;85(4):374-80. doi: 10.1016/j.contraception.2011.08.015. Epub 2011 Oct 28.

Abstract

Background: There are an increase in bone loss during the first 6 months postpartum and a complete recovery postweaning. A few studies of steroid contraceptive use during this period provide some evidence towards protection of bone loss with progestin-only contraceptive methods.

Objective: The study was conducted to evaluate forearm bone mineral density (BMD) of breastfeeding postpartum women using nonhormonal and progestin-only contraceptive methods.

Study design: A prospective cohort study of postpartum women had an analysis performed at 6 months postpartum correlating BMD with contraceptive use. Forearm BMD was measured 7-10 days, 3 months and 6 months postpartum. Eighty-two women were analyzed, comparing nonhormonal (54) and progestin-only (28) contraceptive methods. Information about breastfeeding duration, amenorrhea and body mass index was collected.

Results: Baseline characteristics of the study population showed no statistical differences between the groups. The median duration of breastfeeding for both groups was 183 days. A significant BMD decrease was observed for the nonhormonal group (p<.001); however, no statistical difference was detected for the progestin-only group. Body mass index, BMD at 7-10 days postpartum and total duration of breastfeeding were positively correlated with BMD at 6 months.

Conclusions: Our findings suggest a preventive effect towards postpartum bone loss with progestin-only contraception in breastfeeding women.

MeSH terms

  • Adolescent
  • Adult
  • Bone Density / drug effects*
  • Bone Density / physiology
  • Breast Feeding*
  • Contraception / methods
  • Contraceptives, Oral, Hormonal / administration & dosage
  • Contraceptives, Oral, Hormonal / therapeutic use*
  • Female
  • Humans
  • Lactation / metabolism*
  • Postpartum Period*
  • Progestins / administration & dosage
  • Progestins / therapeutic use*
  • Prospective Studies

Substances

  • Contraceptives, Oral, Hormonal
  • Progestins