Prevalence of bone mineral changes during postpartum amenorrhea and after resumption of menstruation.

The prevalence of significant bone loss after a period of amenorrhea and 1-year follow-up in a cohort of healthy postpartum women was higher at the femoral neck than at the lumbar spine (42% versus 5%). This indicates that reproduction can predispose the proximal femur of a considerable proportion of postpartum women to permanent bone loss.