[Endocrinologic aspects of habitual abortion].

Disorders of the luteoplacental progesterone shift in the first and second trimester lead to a insufficient progesterone secretion, thus constituting an important cause of early and late abortions. The endocrinological disorders caused by ovarian malfunction normally occur between the 5th and 10th weeks of pregnancy. We can distinguish early and late disorders of the corpus luteum graviditatis from a relative luteal deficiency owing to ovarian hyperstimulation. The delayed shift, however, is caused by trophoblast disorders and disturbances of placentation, thus leading to low blood levels of progesterone. Progesterone replacement therapy for the duration of insufficiency leads to significantly reduced rates of abortion. An increase in the rate of malformations is not to be expected.