This retrospective study was carried out at eight Neonatal Intensive Care Units (NICU) Centers worldwide on 33 newborns presenting at birth with pleural, pericardial, or abdominal chylous effusions. Diagnosis of chylous effusion is based on findings of fluid with a milk-like appearance, a concentration of triglycerides in pleural effusion >1.1 mmol/l, and a total cell count >1,000 cells/ml with a predominance of >80% lymphocytes. Thirty-three newborns met the inclusion criteria and were studied. Six subjects who presented at birth with fetal effusion were treated by in-utero pleuro-amniotic shunt. Five of these patients are alive at follow-up. At birth, pleural drainage was performed in 29/33 patients and abdominal drainage was carried out in 3/33. Total parenteral nutrition (TPN) was given to 32/33 patients; 19/23 patients were fed a medium-chain triglycerides (MCT). No adverse effects were observed. Eight patients were treated with Octreotide at dosages ranging from 1 to 7 mcg/kg/hour for 8 to 35 days. All patients showed decreased chylous production. Two patients were treated by pleurodesis. Twenty-two babies are alive after at least 6 months follow-up, 9/33 are deceased, and 2 were lost to follow-up. Clinical conditions of survivors are basically good except for lung involvement [chronic lung disease (CLD) or lung lymphangiectasia] and lymphedema. All patients were using a MCT diet at follow-up with good control of chylous effusion. Visceral chylous effusions of the fetus and neonate are rare disorders, and there currently is only partial agreement on decision-making strategies. We suggest the need for an international prospective trial in an effort to establish the efficacy and effectiveness of diagnostic and therapeutic options described in this article.