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Are Parity & Breastfeeding Related to Fracture Risk?

Obstet Gynecol; ePub 2017 Jun 6; Crandall, et al

Patterns of parity and history of lactation were largely unrelated to fracture risk or bone density in postmenopausal women, a recent study found. Data from 93,676 postmenopausal women (aged 50 to 79 years at baseline) participating in the Women’s Health Initiative Observational Study were analyzed as well as all bone density data from the subset of participants who underwent bone density testing at 3 clinical centers. Researchers found:

  • During mean follow-up of 7.9 years, the incident rate of hip fracture was 1.27%.
  • In adjusted models, number of pregnancies, parity, age at first birth, number of children breastfed, age at first breastfeeding, age at last breastfeeding, and total duration of breastfeeding were not statistically significantly associated with hip fracture incidence.
  • There were no consistent associations of parity or lactation characteristics with overall clinical fracture risk or bone density.
  • However, a history of breastfeeding for at least 1 month was associated with a decreased risk of hip fracture.


Crandall CJ, Liu J, Cauley J, et al. Associations of parity, breastfeeding, and fractures in the Women’s Health Observational Study. [Published online ahead of print June 6, 2017]. Obstet Gynecol. doi:10.1097/AOG.0000000000002096.