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CME Credit Offered
CME Credit Offered
Abstract Award
Abstract Award
Recording available 2/16-5/2
Recording available 2/16-5/2
AIUM Credit
AIUM Credit
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Foundation Awardee
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Abstract Award
Abstract Award
Foundation Awardee
Foundation Awardee

Poster Session 4

Category: Fetal Intervention

Poster Session 4

(1223) Venovenous anastomoses and laser for twin-twin transfusion syndrome (TTTS): a Sequential Trial subanalysis

Thursday, February 12, 2026
3:30 PM - 5:00 PM  
Objective:
To assess the role of venovenous anastomoses (VV) in donor twin survival after laser surgery for twin-twin transfusion syndrome (TTTS).

Study Design:
This is a post hoc analysis of data from the Sequential Trial, a randomized controlled trial (RCT) in which TTTS patients were randomized to sequential vs selective laser surgery. A nested trial randomized patients with superficial anastomoses (ie, arterioarterial [AA] or VV) to ablation of these first (before the principal procedure) vs last (at the conclusion of the laser surgery). Here, in bivariate analyses, we examined donor survival in those with VV vs the control group that had no superficial anastomoses (“No SA,” ie, only arteriovenous communications). We identified patient and surgical characteristics predictive of donor survival for inclusion in multiple logistic regression models, including testing the nested RCT assignment for those with VV to the “Laser First” vs the “Laser Last” groups.

Results:
Of the 642 RCT patients, 64 (10%) had at least 1 VV (range 1-3). Donor live birth in the No SA vs VV groups, respectively, was 421/466 (90.3%) vs 48/64 (75.0%), P=.001. Of the 64 patients with a VV, 28 (43.8%) were randomized to the Laser First group and 36 (56.3%) to the Laser Last group. The proportions of donor twins born alive for the No SA, Laser First, and Laser Last groups, respectively, were 421/466 (90.3%) vs 23/28 (82.1%) vs 25/36 (69.4%), P< .001. In a multiple logistic regression model for donor survival, the VV Laser Last group had a lower odds of survival (aOR 0.24 [0.10-0.58], P=.002) vs the No SA group (Table). A similar model for donor survival that split the VV group into VV only and VV+AA showed that both Laser Last groups (VV only and VV+AA) had lower odds of donor survival (aOR 0.23 [0.06-0.90], P=.035 and aOR 0.24 [0.08-0.74], P=0.013, respectively) vs the No SA group (Table).

Conclusion:
Compared with TTTS patients without superficial anastomoses, patients with VV had worse donor twin survival if the superficial anastomoses were lasered last, at the conclusion of the surgery.