(863) Outcomes after fetoscopic laser photocoagulation for TTTS with or without concomitant selective fetal growth restriction

To compare outcomes after fetoscopic laser photocoagulation (FLP) for twin-twin transfusion (TTTS) with or without concomitant selective fetal growth restriction (SFGR) based on single or dual survival postlaser.

Study Design:

Retrospective cohort study of patients with TTTS treated by FLP in 1 institution between 11/2011 and 04/2023.SFGR was defined by a fetal weight < 10 percentile in 1 fetus and intertwin discordance of >25%. Outcomes were compared between TTTS with no SFGR and TTTS+SFGR.

Results:

186/422(44.1%) patients presented TTTS+SFGR and 236/422(55.9%) presented with isolated TTTS.

Gestational age(GA) (20.1[15.9-29.0] vs 20.1[15.9-27.9] weeks, p=0.53), cervical length at the time of FLP (38[10-70] vs 37[11-57]mm, p=0.3) and rate of PPROM (16/226[7.1%] vs 17/183[9.4%], p=0.19) were similar between TTTS and TTTS+SFGR.

Postlaser dual survival was higher in cases of isolated TTTS (200/236[84.7%] vs TTTS+SFGR 142/186[76.3%], p=0.03).

There were some relevant differences when outcomes between single survivor after FLP with TTTS vs TTTS+SFGR where compared: Main difference before FLP was a higher proportion of stage 3 TTTS in the latter group (83.8% vs 34.6%, p< 0.01), as the proportion of anterior placentas, GA at laser and surgical time were similar. PPROM was more frequent in the TTTS+SFGR group (0 vs 16%, p=0.03), and they delivered at an earlier GA than compared to those with isolated TTTS (33.4 vs 30.0weeks, p=0.04). There were also differences in the proportion of surviving ex donor fetuses at birth (44% vs 12.5%, p< 0.01) and at 30 days of life (50% vs 11.1%, p< 0.01), with higher rates in the isolated TTTS group. In case of dual survival post laser, the proportion of surviving ex-donor were significantly higher at birth and at 30 days in the isolated TTTS group.

 

Conclusion:

FLP for TTTS+SFGR was associated with a decreased rate in dual survival with an increased risk of donor demise. Outcomes in cases of TTTS+SFGR where there was a single survivor were worse than if isolated TTTS was the indication for FLP. Specific explanation of these adverse results need to be elucidated.