[Postmenopausal osteoporosis: pathophysiology and prevention].

Today, it is well known that postmenopausal or type I-osteoporosis can be prevented by an appropriately dosed hormonal substitution. An increased risk for this disease is found approximately in 25% of all women. Consequently, in this high-risk group, there is a clear indication for an oestrogen-progestin-prophylaxis. A high-risk for osteoporosis can be recognized by objective measurements such as bone densitometry or, in a less precise way, by risk factor assessment. The minimal effective oestrogen dose lies by 0.625 mg/day conjugated oestrogens and 2 mg/day oestradiol respectively for oral intake, or 50 micrograms oestradiol daily for supplemented by a progestin either continuously or in a cyclic rate. Prevention of osteoporosis is however not the sole indication for hormonal substitution. Other indications have to be considered in equal rights. In case of doubt, postmenopausal women without counterindications for oestrogen therapy should be permitted to take advantage of hormone substitution.