Postmature pregnancy; clinical obstetric aspects.

Abstract

Postmature pregnancies should be allowed to continue, especially if signs of placental dysfunction are absent. Although the mean fetal birth weight in protracted gestations is slightly greater than that noted in fetuses delivered near term, fear of cephalopelvic disproportion is groundless, and the conduct of labor should be generally supportive and expectant. The increased incidence of complications of labor in patients destined to have protracted gestations is illustrated by the observation of 12.8% of cases of contracted pelvis among 812 postmature deliveries as compared with 7.3% similar cases among 6,603 mature deliveries. Fetal distress (7.5 vs. 3.7%), uterine inertia (5.5 vs. 2.6%), prolonged labor (5.0 vs. 2.5%), and breech presentation (4.1 vs. 2.8%) are likewise significantly higher in incidence among postmature cases. The recognized fetal hazard in prolonged gestation must be weighed against the dangers of routine and often drastic measures taken to prevent postmaturity. Cesarean section is preferable to oxytocic stimulation and frequently proves to be the most conservative measure. Individual appraisal of each case is wiser than the adoption of a routine program of management.