Risks of Preterm Premature Rupture of Membranes and Preterm Birth Post Fetoscopy Based on Location of Trocar Insertion Site

Objective The objective of this study was to assess whether the location of the trocar insertion site for laser treatment of twin-twin transfusion syndrome was associated with preterm-premature rupture of membranes (PPROM) and preterm birth (PTB). Study Design In this study trocar location was documented in the operating room. Lower uterine segment (LUS) location was defined as any insertion <10 cm vertically from the pubic symphysis. Lateral location was defined as 5 cm horizontally from the midline. Patient characteristics were tested against three outcomes: PPROM21 days postoperative, PTB<28 weeks, and PTB<32 weeks. For each outcome, multiple logistic models were fitted to examine the effect of trocar location, controlling for potential risk factors. Results A total of 743 patients were studied. Patients with LUS location were twice as likely as those with a more superior location to have PPROM21 days (OR=2.33, 1.12-4.83, p =0.0236). Patients with both a LUS and Lateral location were over six times more likely to have PPROM21 days (OR=6.66, 2.36-18.78, p =0.0003). Trocar insertion site was not associated with PTB. Conclusion We found that trocar insertion in the LUS, particularly the lateral LUS, was associated with an increased risk of PPROM.