Histologic Chorioamnionitis and Funisitis After Laser Surgery for Twin-Twin Transfusion Syndrome

OBJECTIVE: To estimate the incidence of histologic chorioamnionitis and funisitis after fetoscopic laser surgery for the management of twin-twin transfusion syndrome. METHODS: A case-control study was performed at the Leiden University Medical Center from 2013 to 2014. All patients with twin-twin transfusion syndrome managed with laser surgery during the study period were included and compared with a control group of all monochorionic twins not treated with laser surgery. We excluded patients with fetal demise or higher order pregnancies. Placentas were reviewed for the presence and degree of chorioamnionitis and presence or absence of fetal inflammatory response. The primary outcome was the incidence of histologic chorioamnionitis and funisitis after laser surgery. Odds ratios (ORs) and 95% confidence intervals (CIs) for primary outcomes were calculated. A P value of <.05 was considered as statistical significance. RESULTS: Sixty-two patients treated with laser surgery were included in the study group and compared with 64 patients in the control group. The incidence of histologic chorioamnionitis was 13% (8/62) in the laser group compared with 5% (3/64) in the control group (OR 3.0, 95% CI 0.8-11.9, P=.12). Funisitis occurred in 8% (10/124) in the laser group compared with 0% in the control group (OR 11.1, 95% CI 1.3-96.9, P=.03). Histologic chorioamnionitis with or without funisitis after laser surgery was associated with a shorter laser-to-delivery interval (median 6.6 [range 3.4-14.1] compared with 13.6 [4.4-20.1] weeks, P <.01) and lower gestational age at birth (median 28.1 [range 23.1-32.6] compared with 32.7 [24.4-37.0] weeks, P <.01). CONCLUSION: These findings suggest that laser surgery for twin-twin transfusion syndrome is associated with an increased risk of funisitis.