OP10.04: Trans‐abdominal multifetal pregnancy reduction‐related fetal loss is similar in monochorionic and dichorionic twin pairs

Abstract

To determine whether the risk of fetal loss following trans-abdominal multifetal pregnancy reduction (TA-MFPR) of a monochorionic twin pair is similar to the one in dichorionic pairs. A retrospective review of all TA-MFPR performed in our institution (1999–2007) was conducted. The procedure-related fetal loss, defined as pregnancy loss prior to completion of 24 weeks, in pregnancies involving reduction of a monochorionic pair i.e. “Mono group” was compared to the loss rate in all other TA-MFPR i.e. “Non-mono group”. This comparison was further stratified according to the specific pre and post reduction number of fetuses. Additionally, association between the number of needle insertions performed and the procedure related fetal loss was sought. 394 TA-MFPR were eligible for analysis and an overall loss rate of 2.5% (10 of 394) was detected. The procedure related loss in the “Mono” and “Non-mono” groups as well as the impact of the pre and post reduction number of fetuses on the fetal outcome is displayed in table 1. Information regarding number of needle insertions was available on 182 TA-MFPR of which in 22 “Non-mono” and 16 “mono” cases the same needle insertion was used to reduce more than a single fetus. The loss rate for single, two and three needle insertions was 3/165, 0/11 and 1/6 respectively (p- non significant). Fetal loss following TA-MFPR is independent of the chorionicity of the pair reduced. Additionally, we noted a trend suggesting an increased risk for fetal loss with increased number of needle insertions. Since monochorionic twins carry an increased pregnancy-related complication rate, it is our practice to attempt reduction of such pairs, preferably by using a single needle insertion. This can be achieved by a careful selection of the needle pathway to reach both fetuses.