[Incidence and prerequisites for therapy-independent pregnancy in sterile patients]

15.6% of 857 women who had been treated because of sterility in the infertility centre of the Department of Gynaecology of the University of Heidelberg between May 1982 and June 1985, became pregnant up to June 1986, independent of the therapy. Favourable conditions for the occurrence of pregnancy were provided by secondary sterility and miscarriages in the previous history (in case of non-hormonal disturbances only). Younger women and those whose wish for a child was more recent, had a better chance to experience pregnancy--without any difference between the spontaneously pregnant women and those who became pregnant during treatment. ("Spontaneous pregnancy" signified women who became pregnant either during diagnostic procedure or after having discontinued medical treatment for more than 3 months, in case of tubal microsurgery 12 months). Depending upon the aetiology of surgery, the proportion of spontaneous pregnancies was between 12 and 75%. The rate of spontaneous pregnancies was highest in case of reduced tubal patency (44%), disturbances of hormonal control mechanisms (62.5%) and endometriosis (75%). The spontaneous pregnancy rate was comparable to the overall pregnancy rate (39.4%) in women with uterine malformations (31.4%), immunologic infertility (33.3%), hyperandrogenemia (33.3), hyperprolactinaemia (31.2%) and PCO syndrome (37.5%). The percentage of spontaneous pregnancies was lowest in hypothyroidism (20%), primary ovarian insufficiency (12.5%) and disturbances of the hypothalamic-pituitary axis (16.7%).