Consequences of Selective Fetal Growth Restriction in Perinatal Outcomes after Fetoscopic Laser Photocoagulation for
Leticia Benítez1,2, Romain Corroenne1, Jessian Louis Munoz1
1Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas, USA.
Introduction:
Approximately half of twin-to-twin transfusion syndrome (TTTS) cases are complicated by selective fetal growth restriction (sFGR). Although fetoscopic laser photocoagulation (FLP) is the standard treatment, perinatal outcomes in cases with concomitant sFGR - particularly according to single or dual fetal survival after laser - are not well established. The objective of this study was to compare post-FLP obstetrical and neonatal outcomes between TTTS+sFGR and isolated TTTS, with separate analyses in pregnancies with immediate single or dual fetal survival.
Methods:
This was a retrospective cohort study including all TTTS cases treated with FLP at a single institution between November 2011 and April 2023. TTTS was diagnosed according to Quintero criteria. sFGR was defined as an estimated fetal weight <10th percentile in one twin with an inter-twin weight discordance ≥25% at the time of FLP. Outcomes included immediate post-FLP fetal demise (within 48 h after FLP), preterm premature rupture of membranes (PPROM), gestational age (GA) at delivery, and neonatal survival at birth and at 30 days, analyzed according to post-FLP single or dual fetal survival.
Results:
Among 424 cases, 188 (44.3%) had TTTS + sFGR. GA and cervical length at FLP were similar between groups, but TTTS+sFGR cases showed more severe disease, with a higher proportion of Quintero stage III. Dual fetal survival after FLP was lower in TTTS+sFGR compared with isolated TTTS (iTTTS; 79.6% vs. 88.5%). In pregnancies with single fetal survival post-FLP, TTTS+sFGR was associated with higher rates of delivery before 32 weeks (p = 0.03) and increased post-FLP PPROM (p = 0.03). Ex-donor fetuses in this group had significantly lower survival at birth and at 30 days compared with iTTTS. Even in cases with dual survival post-FLP, ex-donor survival at birth and at 30 days remained lower in TTTS + sFGR, while no other perinatal outcomes differed.
Conclusion:
When stratified by immediate single or dual post-FLP survival, pregnancies with TTTS complicated by sFGR showed consistently worse obstetrical and neonatal outcomes compared with isolated TTTS, particularly due to reduced ex-donor survival across both groups. Further studies are needed to elucidate the mechanisms underlying these findings.
