Persistent compression of uterine insertion on maternal blood dynamic change in fetoscopic laser photocoagulation surgery: a novel method

BACKGROUND: Fetoscopic laser photocoagulation (FLP) has been performed as first-line approach for twin-to-twin transfusion syndrome (TTTS) in monochorionic twin pregnancies. The majority of researches are focusing on advances in fetal treatment and long-term outcome, few researches on maternal surgery-related complications are reported. This study is to compare the maternal blood dynamic changes in women with and without persistent compression on the uterine insertion after the FLP procedure. METHODS: This was a retrospective study conducted at two tertiary referral centers in China between November 2018 and July 2023. TTTS-cases undergoing FLP surgery were enrolled and divided into two groups upon whether having compression on the uterine insertion after FLP. The changes of maternal hemoglobin, hematocrit before and after the procedure were compared between the two groups. RESULTS: A total of 111 TTTS-cases were finally analyzed including 46 cases with persistent compression and 65 cases without persistent compression. The two groups had similar values of hemoglobin (10.7 ± 1.1 versus 10.5 ± 1.2 g/dl, p = 0.513) and hematocrit (32.3 ± 3 versus 31.3 ± 3.2, p = 0.099) before FLP. A similar volume of amniodrainage during the surgery was observed in the two groups (710 ml versus 850 ml, p = 0.255). The decrease in hemoglobin in TTTS-cases with persistent compression was significantly lower than that in TTTS cases without continuous compression (1.1 g/dL versus 1.5 g/dL, p = 0.014). A decrease trend in change of hematocrit was observed between cases with persistent compression (3.1%) and those without persistent compression (4.0%), while it did not achieve a significant difference (p = 0.050). The blood transfusion rate in TTTS-cases with and without compression was 2.2% and 7.7% respectively (p = 0.205). CONCLUSION: The decrease in hemoglobin and hematocrit could be mitigated by persistent compression on the uterine insertion site after FLP, which is an economical, simple and convenient method.