[Calcium and bone metabolism across women's life stages.  Changes of biochemical markers of bone turnover in life cycle of women.] 
Development of bone metabolism markers began about 35 years ago.  Current by the osteoporosis and bone metabolism diseases diagnosis and treatment efficacy.  In childhood and adolescence, bone formation and resorption were increased, but formation rate was exceeded resorption rate.  To keep strength of bone, bone formation and resorption are balanced(remodeling)in the period of maturity, Bone mineral density greatly decreases and biochemical markers of bone turnover markedly increase in postmenopausal women, indicating accelerated bone remodeling because of estrogen withdrawal.  On the other hand, pregnancy and breastfeeding affect bone metabolism.  So, we gynecologists should be careful about bone health with understanding characteristic of bone metabolism markers.