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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
Foundation Awardee
Foundation Awardee
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Abstract Award
Abstract Award
Foundation Awardee
Foundation Awardee

Poster Session 2

Category: Medical/Surgical/Diseases/Complications

Poster Session 2

(600) Transfusion risk among pregnant patients with prior metabolic and bariatric surgery

Wednesday, February 11, 2026
3:30 PM - 5:00 PM  
Objective:
This study aimed to assess associations between history of metabolic and bariatric surgery (MBS), surgery type, and the risk of receiving blood transfusion during delivery admission.

Study Design:
This retrospective cross-sectional study included all deliveries at ≥23 weeks of gestation across seven hospitals within a large New York health system between 2019–2024. Pregnancies with multiple gestations or intrauterine fetal demise were excluded. The primary exposure was a history of MBS. Multivariable logistic regression analysis was used to evaluate the associations between history of MBS and the primary outcome: the odds of receiving a blood transfusion during their delivery admission, adjusting for anemia, race and ethnicity, insurance, history of preterm birth, and multiparity. To examine associations between the type of MBS and transfusion risk, a subgroup analysis of patients with a history of bariatric surgery was conducted with the type of MBS as the primary exposure grouped as: Roux-en-Y gastric bypass, sleeve gastrectomy, gastric banding, or unknown. 

Results:
Among the 156,923 deliveries included, 1,815 patients had a history of MBS.  The rate of transfusion was 3.0% in patients with no history of bariatric surgery and 5.3% in patients with prior MBS. P</span>ost-MBS pregnancy patients were significantly more likely to receive a transfusion during their delivery admission (aOR 1.5, 95% CI 1.03-2.1). Among those with a history of MBS, 48.5% had a sleeve gastrectomy, 6.8% had gastric banding, 23.2% had a gastric bypass, 9.5% had a revision or conversion, and 21.4% had an unknown MBS. The type of MBS was not associated with an increased risk of blood transfusion.

Conclusion:
Pregnant p</span>atients with a history of MBS were significantly more likely to receive a blood transfusion at their delivery.