[Calcium and bone metabolism across women's life stages. Bone metabolism and estrogen/androgen balance in women.]

Androgen as well as estrogen has physical, psychological and sexual roles in women. The action of androgen on bone health in women is important. The androgen receptor is expressed in osteoblasts and osteocytes but the mechanism has not been clarified in women. It has been reported that endogenous testosterone level was positively correlated with bone mineral density and higher testosterone level might be associated with decrease in bone fractures. Also, it has been reported that bone mineral density in women who received testosterone with estrogen was higher than that in women who received estrogen alone. However, it is important to pay attention to occur adverse effects such as hirsutism, acne, disorder of liver function and dyslipidemia. In addition, occurrence of breast cancer and endometrial cancer should be considered. In postmenopausal women, appropriate range of circulating testosterone level may play favor roles in various tissues.