Introduction: Maternal laparotomy-assisted fetoscopic surgery for in-utero myelomeningocele repair has shown that a trans-amniotic membrane suture during fetoscopic port placement can reduce postsurgical complications. Fetoscopic laser photocoagulation (FLP) for complex twins is typically performed percutaneously without a transmembrane stitch. However, in scenarios without a placental-free window, maternal laparotomy may be used for recipient sac access. Here, we present the outcomes of our series of laparotomy-assisted FLP cases, including a trans-amniotic membrane suturing of the fetoscopic port. Methods: Retrospective series of twin-twin transfusion syndrome or twin anemia-polycythemia sequence (TAPS) cases treated at 2 fetal centers that underwent maternal laparotomy to FLP from September 2017 to January 2023. We recorded preoperative and operative characteristics, as well as pregnancy and neonatal outcomes. Results: During the study period, 9 maternal laparotomy to FLP cases were performed. Two were excluded for prior percutaneous FLP in the pregnancy. The remaining seven utilized a maternal laparotomy to trans-amniotic membrane stitch with confirmation of proper suture placement under ultrasound guidance, and all surgeries were performed with a single 10 F Check-Flo® cannula. Mean gestational age (GA) at surgery was 19.1 weeks (range 16 weeks 4 days–23 weeks 3 days), with delivery occurring at a mean GA of 35.0 weeks (range 32 weeks 0 days–37 weeks 1 day), resulting in a mean latency of 15.8 weeks, significantly longer than what is reported in the literature and our own data (mean latency for percutaneous FLP 10.2, 95% CI 9.9–10.5). Furthermore, all cases underwent iatrogenic delivery before labor onset, with the lone delivery prior to 34 weeks due to concern for post-laser TAPS. Conclusion: This case series of laparotomy to FLP with trans-amniotic stitch, demonstrated no cases of spontaneous preterm birth and a longer-than-expected latency from surgery to delivery. Larger studies are warranted to investigate this approach.

Objective: To evaluate the impact of amnioinfusion and other peri‐operative factors on pregnancy outcomes in the setting of Twin‐twin transfusion syndrome (TTTS) treated via fetoscopic laser photocoagulation (FLP).Methods: Retrospective study of TTTS treated via FLP from 2010 to 2019. Pregnancies were grouped by amnioinfusion volume during FLP (<1 L vs. ≥1 L). The primary outcome was latency from surgery to delivery. An amnioinfusion statistic (AIstat) was created for each surgery based on the volume of fluid infused and removed and the preoperative deepest vertical pocket. Regression analysis was planned to assess the association of AIstat with latency.Results: Patients with amnioinfusion of ≥1 L at the time of FLP had decreased latency from surgery to delivery (61 ± 29.4 vs. 73 ± 28.8 days with amnioinfusion <1 L, p < 0.001) and increased preterm prelabor rupture of membranes (PPROM) <34 weeks (44.7% vs. 33.5%, p = 0.042). Amnioinfusion ≥1 L was associated with an increased risk of delivery <32 weeks (aRR 2.6, 95% CI 1.5–4.5), 30 weeks (aRR 2.4, 95% CI 1.5–3.8), and 28 weeks (aRR 1.9, 95% CI 1.1–2.3). Cox‐proportional regression revealed that AIstat was inversely associated with latency (HR 1.1, 95% CI 1.1–1.2).Conclusion: Amnioinfusion ≥1 L during FLP was associated with decreased latency after surgery and increased PPROM <34 weeks.

OBJECTIVE: To describe the pregnancy outcomes of patients who experienced previable and periviable prelabor rupture of membranes (PROM) after the treatment of twin–twin transfusion syndrome. METHODS: We conducted a retrospective cohort study of patients whose pregnancies were complicated by twin–twin transfusion syndrome who were treated with fetoscopic laser photocoagulation at a single fetal center and subsequently experienced PROM from April 2010 to June 2019. Outcomes were infant survival and latency from PROM to delivery. Patients were grouped by gestational age at PROM (before 26 weeks of gestation and 26 weeks or later). The group with PROM before 26 weeks of gestation was stratified by gestational age at PROM for further description of outcomes. RESULTS: Two-hundred fifty of 653 patients (38%) developed PROM, 81 before 26 weeks of gestation and 169 after 26 weeks of gestation. In the setting of PROM before 26 weeks of gestation, the rate of survival of both twins to neonatal intensive care unit (NICU) discharge was 46.3%, compared with 76.9% in the setting of PROM at 26 weeks of gestation or later (P<.001); the survival rate of at least one twin was 61.2% and 98.5%, respectively (P<.001). Fourteen, 22, and 45 patients experienced PROM at 16–19 6/7, 20–22 6/7, and 23–25 6/7 weeks of gestation, respectively. Survival of both twins and at least one twin to NICU discharge was 25.0%, 47.4%, 52.8% (for two) and 33.3%, 47.4%, and 77.8% (for at least one), respectively, among those groups. Fifty-seven of the 81 patients with PROM before 26 weeks of gestation experienced a latency longer than 48 hours. In the setting of PROM before 26 weeks of gestation, when latency lasted longer than 48 hours, overall survival was improved (69.6% vs 53.7%, respectively, P=.017). With latency longer than 48 hours and PROM at 16–19 6/7, 20–22 6/7, and 23–25 6/7 weeks of gestation, survival of both twins to NICU discharge was 60.0%, 61.5%, and 60.7%, respectively, and survival of at least one twin was 80.0%, 61.5%, and 85.7%, respectively. CONCLUSION: Earlier gestational age at PROM after laser photocoagulation is associated with longer latency but lower rates of survival. When PROM occurs before 26 weeks of gestation and latency exceeds 48 hours, rates of neonatal survival are significantly improved.

Objective: Normal Saline (NS) and Lactated Ringer's (LR) damage human amniotic epithelium in vitro when compared with a synthetic amniotic fluid (Amnio‐well, AW). We sought to evaluate the effect of amnio‐exchange with NS, LR, and AW in vivo.Methods: On day E17.5, pregnant rats underwent amnio‐exchange with NS, LR, or AW. Fetuses in each pregnant rat that did not undergo amnio‐exchange acted as controls. Amnions were harvested at E20.5 and ultrastructure evaluated via electron microscopy. Protein levels of cleaved matrix metalloproteinase 9 (MMP9) and collagen 1 (Col1a) were evaluated via Western Blot. Connexin‐43 expression was evaluated via immunofluorescence (IF).Results: There was an increase in amnion microfractures and epithelial cellular shrinkage with NS and LR compared with control and AW. The cleaved MMP9/Col1 ratio was increased 3.9‐fold in NS (p < 0.001) and 4.5‐fold LR (p = 0.0201) relative to control, whereas AW expression was similar to control (p = 0.636). Connexin‐43 was also increased on IF in NS and LR relative to AW (mean gray intensity 26.5 ± 4.5, 26.5 ± 6.7, 19.2 ± 3.4, p < 0.001).Conclusion: Amnio‐exchange with NS and LR led to increased amniotic microfractures and collagen degradation compared with synthetic amniotic fluid. Larger models are warranted to validate or refute these findings.