Osteoporosis and Polycystic Ovary Syndrome.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age and associated with oligo-or anovulation, clinical and/or biochemical hyperandrogenism, and polycystic ovaries. On the one hand, hyperandrogenism might have a protective effect on bone metabolism in affected women. On the other hand, estrogen deficiency is a common feature in PCOS women due to anovulation and might have a negative influence on bone metabolism and peak bone mass in PCOS women. Further, PCOS women frequently suffer from metabolic disturbances such as obesity, insulin resistance, a disturbed glucose metabolism, and the metabolic syndrome, which might also influence bone metabolism. Moreover, pharmaceutical PCOS treatment such as hormonal contraceptives, antiandrogens, and insulin sensitizer might modify risk of osteoporosis and fractures. So far, the literature reports conflicting results on bone mineral density (BMD) in PCOS. Some authors reported no significant differences between PCOS and control women, whereas others found higher or even lower BMD in PCOS women. To date there is only one study on fracture risk in postmenopausal PCOS women and this investigation revealed no significant differences between PCOS and control women. Thus, there is insufficient evidence to answer the question whether PCOS is a risk factor for osteoporosis or not. Therefore, prospective studies among postmenopausal PCOS women including a large number of cases and controls are warranted. So far, every woman affected by PCOS should be evaluated individually regarding risk of osteoporosis and fractures. The relationship of PCOS with osteoporosis should be kept in mind in clinical routine as well as in future studies.