First-trimester intervention in twin reversed arterial perfusion sequence: does size matter?

Area of Science:

• Maternal-Fetal Medicine
• Perinatology
• Fetal Surgery

Background:

• Twin reversed arterial perfusion (TRAP) sequence is a rare complication in monochorionic diamniotic twins.
• It necessitates intervention to prevent fetal demise.

Purpose of the Study:

• To evaluate the outcomes of first-trimester intrafetal laser ablation (IFL) for TRAP sequence.
• To identify potential predictors of pregnancy outcome after IFL.

Main Methods:

• Retrospective analysis of 12 monochorionic diamniotic twin pregnancies with TRAP sequence treated with IFL before 14 weeks of gestation.
• Assessment of intrauterine course and pregnancy outcomes.

Main Results:

• One IFL intervention was sufficient to disrupt the TRAP twin's perfusion in all cases.
• No cases of miscarriage, preterm prelabor rupture of membranes, or hemorrhage occurred.
• Intrauterine fetal demise of the pump twin occurred in 41.7% of cases post-intervention.
• Seven pregnancies resulted in the birth of a healthy infant at term.
• Survivors were treated at a later gestational age and showed different twin size discordance ratios compared to non-survivors, though these did not independently predict survival.

Conclusions:

• First-trimester IFL for TRAP sequence is technically feasible but associated with a significant rate of fetal loss.
• Gestational age at intervention and twin size discordance ratios (CRL-URL/CRL and URL/CRL) are potential predictors of pregnancy outcome.