The obstetric management of non-immunological hydrops.

During the past 8 years, non-Rhesus hydrops has been observed in 31 pregnancies extending beyond 28 weeks gestation. Only three of the babies survived. Antenatal diagnosis is possible by ultrasound examination and although 27 of our patients had at least one indication for this procedure, only 22 were so investigated and in 13, fetal hydrops was demonstrated. Twenty-three were delivered before 36 weeks gestation, 10 by caesarean section of whom none survived; 16 babies were stillborn. Fourteen infants had major cardiovascular anomalies and six had other major malformations. In five infants, infection was thought to be causally related to fetal hydrops and in only four could no cause for the hydrops be found. In five pregnancies the cause of hydrops was discovered antenatally; this influenced subsequent management and two of the five survived. The unexpected appearance of a very abnormal fetal heart rate pattern requires the exclusion of fetal anomaly and non-immunological hydrops. When a diagnosis of non-immune hydrops is made its underlying cause should be sought without delay so that specific treatment may be instituted in the few cases where this is appropriate. A high incidence of complications of the third stage of labour should be anticipated. Subsequent pregnancies are likely to be normal.