Objective. To examine fetal outcome in hydrops fetalis in relation to gestational age at diagnosis and following investigation and treatment.
Methods. All cases of hydrops fetalis presenting to the Fetal Medicine Unit during the last seven years, between 1993 and 1999, were identified from the Fetal Medicine Database. During this time 87 of 13,980 patients who attended the Fetal Medicine Unit had hydrops fetalis. The cases were examined for gestational age at presentation according to etiology and fetal survival following investigation and treatment. The fetal survival rates for non-immune cases of hydrops before and after 24 weeks were compared.
Results. The cause of hydrops was determined antenatally in 71 of the 87 (82%) cases. Of the 51 cases presenting before 24 weeks’ gestation, 23 (45%) were due to chromosomal abnormality. After 24 weeks, fetal tachyarrhythmias and hydrothorax were the most common causes and accounted for 14 (38%) of the 36 cases. Thirty-four cases (39%) of hydrops received intrauterine treatment. The survival rates excluding chromosomal abnormalities in the non-immune cases before and after 24 weeks’ gestation were 31% and 48%, respectively, and were not significantly different.
Conclusions. The survival rate in cases of hydrops fetalis may be improved with appropriate prenatal investigation and therapy. The etiology of hydrops is different before and after 24 weeks, and even when cases of chromosomal abnormality are excluded the survival rate is similar before and after 24 weeks.