[Tocometry and rheobase measurement for cervical insufficiency--contribution to pathogenesis of premature birth (author's transl)].

Longitudinal studies were conducted into 316 high-risk pregnant women, between the 25th and 37th weeks of pregnancy. Insufficiency of the uterine cervix was recordable from 42 women, accounting for 13 per cent of all probands. Tocometry and rheobase measurement were undertaken, complementary to case history evaluation, to elucidate pathogenesis in 30 cases. The mean rheobase value recorded from the above patients was lower with significance than that obtained from a control group. Values were below the lower normal limit in 76 per cent of the cases. Subjective symptoms were recorded by systematic interviews from 26 per cent of the probands. The conclusion drawn from all studies and examinations is that in the majority of all cases cervical insufficiency has been the result of latent, discontinuous labour. Hence, repeated vaginal examination of high-risk pregnant women is considered to be a method for early diagnosis of imminent premature birth. Conclusions are suggested for the practitioner.