Nonimmune hydrops fetalis: two decades of experience in a university hospital

To identify the etiology of nonimmune hydrops fetalis cases in pregnant women diagnosed and referred for prenatal care. Retrospective analysis of cases with nonimmune hydrops fetalis that were monitored between March 1992 and December 2011. Diagnosis was confirmed by the presence of fetal subcutaneous edema (≥ 5 mm) with effusion in at least one serous cavity using obstetric ultrasound, and etiological investigation was conducted with cytogenetic (karyotype), infectious (syphilis, parvovirus B19, toxoplasmosis, rubella, cytomegalovirus, adenovirus and herpes simplex), hematologic and metabolic (inborn errors) analysis and fetal echocardiography. Twin pregnancies were excluded. Statistical analysis was performed using the χ² test for adhesion (software R 2.11.1). We included 116 patients with nonimmune hydrops fetalis; the etiology was elucidated in 91 cases (78.5%), while 25 cases (21.5%) were classified as idiopathic. Most cases had a chromosomal etiology, for a total of 26 cases (22.4%), followed by lymphatic etiology with 15 cases (12.9% with 11 cases of cystic hygroma), and cardiovascular and infectious etiology with 14 cases each (12.1%). In the remaining cases, the etiology was thoracic in 6.9% (eight cases), malformation syndromes in 4.3% (five cases), extrathoracic tumors in 3.4% (four cases), metabolic in 1.7% (two cases), and hematologic, gastrointestinal and genitourinary in 0.9% (one case each). During the postnatal period, 104 cases were followed up until the 40th day of life, and 12 cases had intrauterine fetal death. The survival rate of these 104 newborns was 23.1% (24 survived). An attempt should be made to clarify the etiology of hydrops diagnosed during pregnancy since the condition is associated with a wide spectrum of diseases. It is especially important to determine whether a potentially treatable condition is present and to identify disease at risk for recurrence in future pregnancies for adequate pre-conception counseling.