OP23.04: Selective reduction in complex triplet pregnancy by radio frequency ablation: single centre experience

Abstract

The risk of miscarriage and preterm delivery are significantly higher in multiple pregnancies with a monochorionic pair. Intra fetal anastomosis in monochorionic (MC) pair preclude the use of intracardiac potassium chloride and fetal reduction must be performed using cord occlusion techniques such as bipolar cord coagulation, interstitial laser or by radiofrequency ablation. We present our series of selective reduction in complex triplet pregnancy with an MC pair using radiofrequency ablation (RFA). This was a retrospective study of the procedures in our unit for the period between 2010 and 2016. We had 25 cases of complex triplets (19 Dichorionic and 6 Monochorionic triplets). The indications for fetal reduction include 14 of multifetal pregnancy reduction, 9 cases of TTTs in the Monochorionic pair, 1 of fetal anomaly in co twin and 1 of discordant growth in the MC pair. Outcome data was available in 24 cases. Median GA at procedure was 15.4 weeks (range 12.1-21.7) and at delivery was 32.9 weeks (range 17.4-41). We had 3 miscarriages; 2 cases occurred within 2 weeks of procedure. IUD of the co-twin occurred in 3 cases (2 in DCTA and 1 in MCTA). The median GA at delivery following MFPR in complex triplets was 34.6 weeks and in the TTTS group was 32.3 weeks. Complications included complex thermal injury to the co twin in 1 case resulting in the subsequent termination of the co twin. There were no cases of neurological impairment in the survivors post procedure. This is the largest case series of fetal reduction in complex triplets by RFA. Selective reduction by RFA in complex triplet pregnancies resulted in a total pregnancy loss in 12.5% of the cases with an 87.5% favourable outcome, in other words two live babies at discharge from hospital. The gestational age was higher at delivery in the MFPR group compared to other indications for selective fetal reduction. This data is useful in appropriate counselling of complex triplex pregnancies.