Poster Session 3
Billie R. Lianoglou, MS (she/her/hers)
Genetic Counselor
Center for Maternal-Fetal Precision Medicine, University of California San Francisco
San Francisco, California, United States
Evangelia Vlachodimitropoulou, MD
Mount Sinai Hospital and University of Toronto
Toronto, Ontario, Canada
Akos Herzeg, MBA, MD, PhD (he/him/his)
Associate Professor
UCSF
San Francisco, California, United States
Tippi C. MacKenzie, MD (she/her/hers)
Professor of Surgery
University of California, San Francisco
San Francisco, California, United States
Greg Ryan, MD
Head, Fetal Medicine program & Ontario Fetal Centre
University of Toronto
Toronto, Ontario, Canada
Juan Gonzalez, MD, MS, PhD (he/him/his)
Perinatologist Division Director, Maternal-Fetal Medicine & Reproductive Genetics Director, Center f
Center for Maternal-Fetal Precision Medicine, University of California San Francisco
San Francisco, California, United States
To understand the impact of in-utero blood transfusion (IUT) performed > 35 weeks’ gestation (WG) on perinatal outcomes in fetuses with alpha thalassemia major (ATM).
Study Design:
UCSF established an international patient registry for patients affected by ATM which includes all patients referred to our institution and collaborating sites. We conducted a retrospective chart review and prospective enrollment of registry participants, including all singleton pregnancies with ATM who underwent IUTs and received their last IUT >32 WG. Data collected covered prenatal and postnatal outcomes, including details of IUTs. Patients were stratified into two groups based on the timing of the final IUT: A: 32-35 WG (N=17), B: > 35 WG (N=10). Fisher’s exact test and unpaired t-test were used to assess the association between the gestational age (GA) of the final IUT and key outcomes such as survival rate, 5’ APGAR scores, the need for mechanical ventilation, prolonged neonatal hospitalization, GA at delivery, and time between last IUT and delivery.
Results:
There were no differences between groups in the mean age at first IUT (A 25.2, B 23.8; P= 0.41) or the presence of hydrops upon presentation. Extension of IUTs beyond 35 weeks allowed for delivery later in gestation (A 37.4, B 38.3; P< 0.0001), with a shorter time interval between IUT and delivery (A 3.4, B 2.07; P=0.01). There were no adverse outcomes associated with extended IUTs as evidenced by survival rate (A 100%, B 90%; P=0.37), 5’ APGAR < 7 scores (A 88%, B 90%; P= >0.99), need for mechanical ventilation (A 24%, B 20%; P >0.99); there was a trend for decreased rates of prolonged hospitalization (A 53%, B 22%; P=0.22).
Conclusion:
Expert opinion recommends performing IUTs up to 35 WG, with subsequent planned delivery 2-3 weeks later. However, our analysis indicates that IUTs performed beyond 35 WG are not associated with higher morbidity but allow for later GA at delivery without an additional risk of urgent delivery or other adverse perinatal outcomes.
