Bart's hydrops fetalis--clinical presentation and management--an analysis of 25 cases.

Twenty-nine hydropic infants were born in the Kandang Kerbau Hospital between 1980 and 1985, during which there were 131,658 deliveries, giving an incidence of 1 in 4,540 total births. Twenty-five of these cases were confirmed to be due to homozygous alpha thalassaemia. No case of fetal hydrops due to Rh isoimmunization was detected. The mean age of the mothers was 28.86 +/- 4.05 years (+/- SD). Eight patients had delivered 1 hydropic baby previously while 1 had a history of 2 babies with hydrops fetalis; 92% of the patients had been followed antenatally while 8% were first seen when they were admitted in labour; 25% of the patients had anaemia, 52% had polyhydramnios, 20% developed hypertension and 64% had bilateral lower limb oedema. None of the patients had concomitant hypertension, generalized oedema and proteinuria. In 4 cases of recurrent hydrops, serial ultrasound scans were performed from early pregnancy but ultrasonic features of hydrops fetalis were only seen from 27 weeks' gestation. Spontaneous labour occurred in 75% of patients at a mean of 32.3 +/- 3.3 weeks (+/- SD). All delivered vaginally and only 1 patient required abdominal decompression. Four patients required Caesarean section, 2 for failure to progress after induction of labour, 1 for major placenta praevia and the fourth for fetal distress; in the last case, diagnosis of hydrops fetalis was only made after delivery of the baby. All the babies in the series died within one hour of delivery. Homozygous alpha thalassaemia is the commonest cause of hydrops fetalis in Singapore and is an invariably fatal condition. It is associated with an increased incidence of maternal anaemia, polyhydramnios and prematurity.