Nonimmune hydrops fetalis (NIHF) is a fetal condition in which an overaccumulation of fluid in the interstitial tissues of the fetus occurs. NIHF is a separate condition from fetal immune hydrops caused by Rh incompatibility. There are multiple etiologies associated with NIHF, such as genetic disorders, fetal anemia, infectious diseases, twin-to-twin transfusion syndrome, and cardiovascular abnormalities. NIHF is an uncommon, predominantly fatal finding. The obstetric patient may present large-for-gestational age but is Rh compatible. Fetal anatomy may demonstrate multiple findings, including gross skin thickening, polyhydramnios, pleural or pericardial effusions, fetal ascites, and thickened placenta.
American Academy of Pediatrics and the American College of Obstetricians and Gynecologists: Guidelinesfor Perinatal Care. 5th ed. Elk Grove Village, IL, AAP/ ACOG, 2002.
