Monochorionic triamniotic (MCTA) triplet pregnancy complicated by TRAP sequence: successful management with ultrasound-guided radiofrequency ablation and favourable outcome

We present a case of a 30-year-old G3P2L1 with a spontaneously conceived monochorionic triamniotic (MCTA) triplet pregnancy complicated by a Twin Reversed Arterial Perfusion (TRAP) sequence in one fetus. Early ultrasound at 10 weeks 4 days showed MCTA triplets with one hydropic fetus with alobar holoprosencephaly. A review scan at 12 weeks 6 days gestation showed that this fetus with holoprosencephaly had no heart. Colour Doppler showed a single artery in the acardiac fetus, suggestive of twin reverse arterial perfusion (TRAP sequence). Ultrasound-guided radiofrequency ablation (RFA) was successfully performed at 19 weeks and 2 days. The patient required cerclage at 23 weeks due to cervical shortening. She was delivered by Caesarean section at 33 weeks and 5 days in view of fetal growth restriction and abnormal Dopplers in twin 2. Both babies, weighing 1625g and 1460 g, were discharged well after 7 & 11 days of NICU stay. This case highlights the importance of early diagnosis, ultrasound surveillance, timely intervention, and multidisciplinary care in the management of this extremely rare triplet pregnancy.