The SWAN study is a multicentric, consisting of 7 centers in which observation of ethnically different groups of middle age females was carried out. It describes the timing and normal variations of biologic and psychological characteristics in the period before, during and after menopause in 5 ethnic groups by means of collecting, analyzing and publishing information of health condition, physical parameters symptoms, life-style, attitudes and medical care exploitation.
The obtained data were published in the papers given in the literature survey. The SWAN study ran in three phases.