OP23.05: Procedure outcomes of embryo reduction and selective feticide with multifetal pregnancy to twin or singleton pregnancy: a retrospective study

Abstract

To study the procedure related adverse events and the outcomes of women with multifetal pregnancy, defined as twin or more fetuses that was reduced to twin or singleton pregnancy at different gestational ages. We analysed retrospective data consisted of 382 multifetal pregnancy cases that underwent embryo reduction and selective feticide between 2006.12 and 2017.01. Out of total cases, 179 cases underwent early transvaginal selective embryo reduction (mean 7.6 weeks gestation) and 203 cases underwent selective feticide (mean 13.4 weeks gestation) with KCL injection in the vicinity of the fetal heart via transabdominal approach after ultrasound screening for nuchal translucency and anatomical defects. Procedure outcomes were compared between the two groups. The results showed significant differences between 2 groups (embryo reduction vs. selective feticide) in incidence of procedure related adverse events. The percentage of women with all surviving fetuses after 4 weeks of procedure was significantly higher in selective feticide group (92.0% vs. 98.2%, p=0.009) and the percentage of women with overall procedure related pregnancy loss (defined one and two losses of fetuses after 4 weeks of procedure) was significantly less in selective feticide group (8.0% vs. 1.8%, p=0.009). Incidence of subchorionic hematoma defined by ultrasound after 1 and 4 weeks of the procedure was significantly higher in the embryo reduction group (1 week; 59.8% vs. 27.9% p<0.001, 4 weeks; 34.2% vs. 4.8% p<0.001). Selective feticide group showed less incidence of procedure related adverse events, such as subchorionic hematoma and fetal loss compared to embryo reduction group. Although both procedures are accepted approach in multifetal pregnancy reduction, spontaneous demise of one fetus may occur after embryo reduction, and selective feticide has benefit in enabling chorionic villus sampling and ultrasound screening for nuchal translucency and anatomical defects before the procedure.