Having two or more in utero transfusions (IUTs) usually results in full-term births and good neurodevelopment in fetuses diagnosed prenatally with alpha thalassemia major, researchers reported in Blood Advances.
“It’s really given hope,” said Billie Lianoglou, LCGC, MS, of the University of California, San Francisco (UCSF) Center for Maternal-Fetal Precision Medicine, who helped lead the study. “No pregnancy has a guarantee of a good outcome, but what we were able to show is that offering [IUTs] earlier is ideal.”
The findings offer what is possibly the most definitive data yet on the benefits of IUTs for alpha thalassemia major, which is often first seen on prenatal ultrasound, with pleural and pericardial effusion, ascites, and skin edema. Alpha thalassemia carrier status is seen at a rate as high as 51% in Vietnam, 20% to 40% in other Southeast Asian countries, and 5% in the Americas. Alpha thalassemia major develops when both biological parents are affected by or are carriers of alpha thalassemia. The disorder typically results in fetal death if IUTs aren’t performed, and parents are frequently counseled to terminate the pregnancy.
Despite the growing understanding that fetal therapy is an option for alpha thalassemia major, there is a relative reluctance to offer IUTs for this condition, in part because of limited literature demonstrating the benefit of fetal therapy on postnatal outcomes.
In the present study, researchers analyzed data from a registry of patients referred to UCSF from around the world. Sixty patients were enrolled: 56 with alpha thalassemia major and four with similar types of alpha thalassemia that involve different genetic variants.
Forty-nine cases were diagnosed prenatally. In 30 of these, medical abortion was chosen. Among the other 19 pregnancies, the 14 infants who received at least two IUTs survived to discharge from the hospital. Of the five fetuses that had no transfusions or just one, all died near the time of birth.
IUTs carry a risk of technical complications, including fetal death and pre-term delivery. Of the patients who received IUTs, three delivered pre-term. Hydrops resolved in all 12 patients with this symptom who had two or more IUTs, compared to two out of three among those with no or one IUT and one of four among those diagnosed after birth.
Among those patients who received at least two IUTs, the composite scores overall on the Vineland-3 neurodevelopmental assessment were in the 59th percentile, and the scores of these patients fell within the normal range. Researchers found, though, that the earlier the first IUT, the higher the scores.
Ms. Lianoglou said more centers are acknowledging that IUTs can be effective and are offering transfusions. Not all parents choose to continue with the pregnancy, however, because of the possibility of a complicated outcome and the demands of undergoing the transfusions, but having the option allows them to make an informed choice.
One of the study participants had a fetus with alpha thalassemia major but was not treated with IUT, and the infant died right after birth. In her next pregnancy, alpha thalassemia major was diagnosed by amniocentesis, and she connected with UCSF for treatment.
“Now she has this beautiful boy,” Ms. Lianoglou said. “Same diagnosis and two pregnancies, and a very different outcome.”
Any conflicts of interest declared by the authors can be found in the original article.
Reference
Schwab ME, Lianoglou BR, Gano D, et al. The impact of in utero transfusions on perinatal outcomes in patients with alpha thalassemia major: the UCSF registry [published online, 2022 Oct 28]. Blood Adv. doi: 10.1182/bloodadvances.2022007823.