[The clinical significance of post-term pregnancy after prospective determination of delivery date (author's transl)].

From 1978 to 1980, 3300 patients had their delivery terms prospectively determined by ultrasonic measuring the first half of pregnancy. - 18.4% had a pregnancy of 281-293 days. Post-terms were found in 1.5%. - Care during pregnancy followed a standardised scheme, beginning on the 281st day. Statistical evaluation of all delivery terms shows an asymmetrical Gaussian distribution. In pregnancies up to 293 days abnormal CTG was found in 7.7%, a prepathological, resp. pathological oxytocin sensitivity test observed in 1.5%. With frequent parallel CTG-checks, amnioscopy is of lesser clinical relevance. Deliveries by forceps or vacuum extraction as well as caesarian sections were not more frequent than in a 280-days-term population. No higher perinatal mortality was observed. - In post-terms meconium was found sub partu in 31.4%. The rate of caesarian sections in post-terms shows an increase to 19.6%, but only to 10.5% in prolonged terms. 1 min. post partum the newborns show a slightly accentuated clinical depression (Apgar 4-6) compared with the control group. However, 5 min. post partum Apgar figures as well as umbilical arterial ph indicate no significant difference. No occurrence of perinatal mortality was registered. With appropriate control (resp. CTG) and management of delivery, higher risks are not to be anticipated for mothers and newborns.