the influence of pregnancy and lactation on maternal bone health: a systematic review.

osteoporosis is considered as an important public health problem especially in postmenopausal women. there are some hypotheses support the contributory effect of pregnancy and lactation on osteoporosis later in life. high calcium demand during pregnancy and lactation and low estrogenic state support those hypotheses. numerous studies have investigated on the issue but there is no consensus about the contributory effect of pregnancy and lactation on osteoporosis. to explore the current state of fact, in the present study, all bibliographic databases were searched and all relevant studies on the topic of osteoporosis, lactation, and pregnancy were reviewed. the review shows that despite of controversial results, pregnancy may have protective effect on bone especially if followed by lactation.