Outcome of laser photocoagulation in monochorionic diamniotic twin pregnancy complicated by Type‐II selective fetal growth restriction

Abstract

ABSTRACTObjectivesTo evaluate the outcome of monochorionic diamniotic (MCDA) twins complicated by Type‐II selective fetal growth restriction (sFGR) who underwent fetoscopic laser photocoagulation and to validate a previously proposed subclassification system for Type‐II sFGR in a large multicenter cohort.MethodsThis retrospective multicenter cohort study included all MCDA twins complicated by Type‐II sFGR who underwent laser photocoagulation of placental anastomoses at four large tertiary fetal‐care centers between 2006 and 2020. Cases were subclassified according to a recently proposed system based on Doppler evaluation of the ductus venosus (DV) and middle cerebral artery (MCA) into Type‐IIA (normal DV flow and MCA peak systolic velocity (PSV) of the growth‐restricted fetus) or Type‐IIB (absent or reversed flow in the DV during atrial contraction and/or MCA‐PSV ≥ 1.5 multiples of the median of the growth‐restricted fetus). Demographic characteristics and pregnancy outcomes were compared between the groups. Data are presented as mean ± SD or n (%) as appropriate. P‐values < 0.05 were considered statistically significant.ResultsA total of 98 patients with MCDA twins met our inclusion criteria, with 56 subclassified as Type IIA and 42 as Type IIB. Demographic characteristics were similar between the groups; however, Type‐IIB cases had a significantly earlier gestational age at diagnosis and at laser surgery, as well as larger intertwin estimated fetal weight discordance, which may be a reflection of disease severity. Postnatal survival of the growth‐restricted fetus to 30 days of age was significantly lower in Type‐IIB compared to Type‐IIA cases (23.8% vs 46.4%; P = 0.034).ConclusionsIn MCDA twins complicated by Type‐II sFGR and treated with laser photocoagulation of placental anastomoses, preoperative Doppler assessment of the DV and MCA helped identify a subset of patients at increased risk of demise of the growth‐restricted fetus following intervention. This study provides valuable information for guiding surgical management and patient counseling. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.