Sirenomelia is a rare and fatal congenital defect characterized by varying degrees of lower limb fusion, thoracolumbar spinal anomalies, sacrococcygeal agenesis, genitourinary, and anorectal atresia.There is a strong association with maternal diabetes where relative risk is 1:200-250 and up to 22% of fetuses with this anomaly will have mothers with diabetes.A 34-year-old unbooked G3P2L2 at 35 weeks 5 days of gestational age with previous two live vaginal birth was admitted in the labor room with pain in the abdomen. She had no history of prior antenatal care and belonged to a tribal community with lower socioeconomic status.She was otherwise healthy with no known history of genetic or congenital anomaly in her family. Baby not cried after birth , no activity and hypotonia present . Immediately intubated with ET NO 3 and bag and tube ventilation given and shifted to NICU and put on ACMV mode of ventilationAnomalies observed in sirenomelia are described as the most severe form of caudal regression syndrome. Fusion of the lower extremities, presence of single umbilical and persistent vitelline artery are major features of sirenomelia . Although the primary molecular defect resulting in sirenomelia remains unclear, two main pathogenic hypotheses namely the vascular steal hypothesis and the defective blastogenesis hypothesis are proposed.Sirenomelia is a rare and lethal congenital anomaly. When diagnosed antenatally, termination should be offered. However, prevention is possible and should be the goal.
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