Sad Fetus Syndrome: Molar Placenta Meets a Live Fetus

Aim and background: "Sad fetus syndrome" is a rare clinical entity in which a live fetus with a normal karyotype coexists with a partial molar placenta, which has a triploid karyotype.Gestational trophoblastic disease (GTD) includes benign and malignant conditions such as complete and partial hydatidiform moles, invasive moles, choriocarcinoma, epithelioid, and placental trophoblastic tumors.Typically, partial molar pregnancies result in fetal loss or severe congenital anomalies, but in rare cases, a live fetus with a normal diploid karyotype survives.This case report aims to explore this rare condition and discuss its clinical implications.Case description: A 30-year-old woman, G2P1L1, at 38 weeks gestation, with a history of a previous cesarean section, presented with severe abdominal pain.She was diagnosed with partial molar pregnancy after undergoing an emergency cesarean section due to scar tenderness.A healthy 2.8 kg female neonate was delivered, and the placenta showed features of a partial mole, including vesicular swelling.Histopathological examination confirmed the diagnosis.The baby had a normal karyotype (46 XX), with no congenital abnormalities or developmental delays, and grew normally during the 1 year follow-up.Weekly beta-HCG (human chorionic gonadotropin) levels were monitored, returning to normal after 8 weeks, with no evidence of malignant transformation.Conclusion: Partial molar pregnancies with a live fetus possessing a normal diploid karyotype can result in favorable neonatal outcomes.Proper prenatal care, including regular monitoring, ultrasounds, and amniocentesis, is essential to ensure the health of both the mother and the fetus.Timely intervention and postpartum surveillance are crucial to detect potential complications such as gestational trophoblastic neoplasia (GTN).Clinical significance: "Sad fetus syndrome" is clinically significant due to its rarity and the complexities involved in managing both maternal and fetal health.Early detection and comprehensive management, including antenatal monitoring, delivery planning, and postpartum evaluation, are vital for achieving the best outcomes for both the mother and neonate.