Complex multiple pregnancies: what's new?

Abstract

This issue of the journal is specifically dedicated to complicated multiple pregnancies and gathers some of the latest research in the field. The incidence of twins and higher order multiples has been rising over the past decades, partly due to an increased use assisted reproductive technologies (ART). The latter particularly leads to a higher incidence of monochorionic twins, which occur spontaneously in 0.4% of the total population but in about 2% of all pregnancies conceived after ART. 1 Monochorionic twins have much higher rates of complications than dichorionic twins due to their specific placental angioarchitecture which can lead to complications such as twin-twin transfusion syndrome (TTTS; in 10%-15% of cases), 2 selective growth restriction (sIUGR; in 15% of cases), 2 twin-anemia-polycythemia sequence (TAPS; in 4% of cases) 3 and twin-reversed-arterialperfusion syndrome (TRAP; in 1%-2%). 4 Thanks to close surveillance strategies, the detection rates of these anomalies have improved significantly 5 and this has allowed for the introduction of treatments such as fetoscopic laser ablation of placental anastomoses, 6 bipolar cord occlusion and radiofrequency ablation. 7