Researchers have identified a positive correlation between hemolytic disease of the fetus and newborn (HDFN) survival and the World Bank income class of the country where the pregnancy took place. The study was recently published in the American Journal of Obstetrics and Gynecology.
HDFN is a disease in which maternal antibodies travel through the placenta and bind to fetal red blood cells, destroying them. The destruction of fetal blood cells leads to anemia and the incapacity to correctly transport oxygen throughout the body.
Intrauterine blood transfusions, in which red blood cells are transfused directly into the fetus through the uterus, are currently the treatment of choice for fetal anemia due to HDFN. However, as with any invasive procedure, there are risks associated with intrauterine transfusions, such as infection, bleeding, and premature birth.
The authors of the new study aimed to assess the outcomes of pregnancies with HDFN that required intrauterine transfusion in hopes of finding factors capable of predicting survival.
See how the care of women with HDFN has improved
Researchers used the combined data of 38 studies, including a total of 2200 pregnancies in 18 countries. The studies were published between 1990 and December 2021.
Results showed that most intrauterine transfusions due to HDFN occur in the third trimester, around week 26 of gestation. Hydrops, a known complication of HDFN in which liquid accumulates in the skin and other body cavities, occurred in about 30% of cases.
The average hemoglobin levels previous to transfusion were around 6 grams per deciliter (around 6 points below normal value) and 12 grams per deciliter at birth. The average survival rate was approximately 83%.
The authors found that a higher World Bank income class of the county where the pregnancy occurred was associated with better survival. Other factors associated with better survival were higher pre-transfusional hemoglobin and the absence of hydrops.
“Our findings suggest that investment in healthcare infrastructure has the potential to address barriers such as delayed presentation and limited access to screening and advanced care,” the authors concluded.
