Radial Expansion of Chorioamniotic Membranes After Perforation Causes Less Damage Than Fixed Diameter Instruments

OBJECTIVE: Iatrogenic preterm premature rupture of membranes (iPPROM) complicates up to 40% of fetoscopic surgeries, driven by the limited healing potential of the chorioamniotic membrane after perforation. While radial expansion reduces tissue damage in other surgical fields, its application in fetal surgery remains unexplored. METHODS: We compared perforations in fresh chorioamniotic membranes created by three devices: standard 2 mm (6Fr) and 4 mm (12Fr) sheathed trocars, and an angioplasty balloon that radially expands from 2 to 4 mm. Perforation dimensions (height, width, area) and shape regularity were analyzed. RESULTS: The angioplasty balloon created perforations with an area comparable to the 2 mm trocar and significantly smaller than the 4 mm trocar. Furthermore, the balloon produced more regularly shaped holes (circles/ellipses), while the 12Fr trocar most often created irregular defects. CONCLUSION: Radial expansion minimizes after perforation chorioamniotic membrane damage and promotes more regular perforation shapes. This approach warrants further investigation as a potential strategy to reduce iPPROM incidence in fetal therapy.