A study assessing hemolytic disease of the fetus and newborn (HDFN) in a medical center found a significant decrease in the proportion of patients with severe HDFN compared with historical estimates, according to a study recently published in Maternal-Fetal Medicine.
HDFN is a disease that is provoked when the mother produces antibodies that attack the red blood cells of her fetus. The most common cause of this is Rhesus D incompatibility. However, over the years, the implementation of both preventive and therapeutic measures have led to a reduction in HDFN cases.
At the medical center under investigation, since 2000, women of reproductive age alongside female children have received Kell-negative red blood cells; starting from 2008, red blood cells compatible with Rhc, RhE, RhC and RhE antigens were also used.
A unique point of approach in this study was the implementation of a standardized algorithm to monitor immunized pregnancies and to refer cases that required intrauterine transfusions to a dedicated specialized center.
Read more about HDFN testing and diagnosis
This prospective study collected data on pregnant/immunized women and their children between 2010 and 2023. The authors of the study were primarily concerned with the incidence of anti-D and non-D antibodies in pregnancies, as well as cases of severe HDFN caused by specific antibodies; all the data collected were compared with historically available information.
In this study, RhD-positive pregnant women participated in antibody screening at 12 weeks and at 34 weeks; meanwhile; RhD-negative women were tested at the 12th, 28th, and 34th weeks of pregnancy, as well as immediately during the postpartum period. Rhesus prophylaxis was administered to RhD-negative women when indicated.
The research team reported on the data of a total of 180 women comprising 198 pregnancies. Among these 180 women, 24 (12%) were found to have multiple clinically relevant alloantibodies. This study reported an incidence of 0.96% in terms of the incidence of anti-D antibodies discovered in RhD-negative women; meanwhile, the incidence of non-D antibodies in all pregnancies under investigation was 0.17%. As expected, the most commonly detected antibody was anti-D, while the most common non-D antibodies were anti-c, anti-E and anti-K.
Among the 198 pregnancies, 14 were excluded as a result of missing data. As for the remaining 184 pregnancies, 132 newborns were found to be antigen-positive, 95 were DAT-positive, and 30 were diagnosed with severe HDFN. Among these 30 cases, the vast majority were caused by anti-D antibodies.
Overall, the frequency of severe HDFN associated with anti-D and anti-D antibodies was 4.9 per 10,000 live births; which is significantly lower than that of historical estimates. This was similarly the case in terms of severe HDFN.
“Uniform criteria for clinically relevant RBC antibodies and severe HDFN are recommended for comparing the frequency of these conditions across different centers and countries,” the authors of the study wrote. “When comparing the results of this study with the historical control, we used the same criteria and found a statistically significant decrease in severe HDFN.”
Sign up here to get the latest news, perspectives, and information about HDFN sent directly to your inbox. Registration is free and only takes a minute.
