Parapagus dicephalus dipus tribrachius conjoined twins: a case report.

Conjoined twins are a rare occurrence, affecting approximately 1.47 per 100,000 live births as a result of the incomplete splitting of the embryo in monochorionic monoamniotic pregnancies, after 13-14 days post-fertilization. Early prenatal diagnosis through ultrasound between 11 and 14 weeks is crucial for counseling and management decisions, including pregnancy termination or continuation with the support of a multidisciplinary team. We report a case of a 17-year-old primigravida referred in the third trimester with an ultrasound diagnosis of parapagus dicephalus dipus tribrachius conjoined twins. Delivery was by elective cesarean section, and the twins shared a single heart with three ventricles, two atria, a large atrial septal defect, and an incompetent atrioventricular valve. They died of sepsis on day 20 post-delivery. In our setting, anomaly scans during the second trimester are rarely or never performed, highlighting the need for routine early anomaly scans to enable timely intervention and improve outcomes in similar cases.