The prognostic factors and outcomes of primary fetal hydrothorax with the effects of fetal intervention

Objectives This study aims to determine the prognostic factors and outcomes of primary fetal hydrothorax (FHT) and investigate the effects of fetal therapy. Methods A nationwide survey was conducted on fetuses with primary FHT delivered after 22 weeks of gestation between January 2007 and December 2011 at perinatal centers. Results Among the 287 cases of primary FHT, the survival rates for those with and without hydrops were 58.0% (113/195) and 97.8% (90/92), respectively. The survival rates in the no-therapy, thoracocentesis, and thoracoamniotic shunting (TAS) groups in the hydropic cases and the non-hydropic cases were 59.7% (40/67), 51.5% (35/68), and 63.3% (38/60) and 98.1% (53/54), 96.3% (26/27), and 100% (11/11), respectively. The crude relative risk for death was 2.1 (p = 0.005) for fetuses diagnosed at 26 to 30 weeks of gestational age (vs ≥30 weeks), 2.3 (p = 0.001) for both skin edema and ascites, and 3.1 (p = 0.02) for bilateral pleural effusion. TAS was associated with a significant risk reduction for death in hydropic cases [adjusted relative risk 0.61, p = 0.01 (vs no fetal therapy)]. Conclusions Hydrops and an early gestational age at diagnosis (<30 weeks of gestation), skin edema with ascites, and bilateral effusion predicted a poor prognosis in primary FHT cases. TAS was associated with a higher survival rate. © 2016 John Wiley & Sons, Ltd.