Iron Studies in Infants Born to an Iron Overloaded Mother With β-Thalassemia Major: Possible Effects of Maternal Desferrioxamine Therapy

Abstract

A 30-year-old woman with transfusion-dependent, homozygous beta-thalassemia major and transfusional hemosiderosis had 2 successful pregnancies after ovulation induction and in vitro fertilization. Treatment with subcutaneous desferrioxamine (DF) was discontinued before the conception but restarted at 6 months of gestation. Elective cesarean section was performed at 35 weeks of pregnancy because of partial placenta previa. The infant was clinically normal. At the time of delivery, the maternal serum ferritin was 2000 ng/mL, serum iron/iron binding capacity (SI/TIBC) were 274/380 microg/dL, and % saturation 72%. Serum ferritin level in the infant was 42 ng/mL, SI/TIBC were 53/222 microg/dL, and % saturation 23%. During a twin pregnancy 2 years later, DF therapy was totally withheld. Elective cesarian section was performed at 36 weeks of gestation. Both twins were clinically normal. At delivery, the maternal serum ferritin was 1700 ng/mL, SI/TIBC 447/450 microg/dL, and % saturation 99%. Serum ferritins of the twins were 227 and 203 ng/mL, SI/TIBC were 30/182 and 27/203 microg/dL, and % saturations 16% and 13%. Despite elevated iron studies in the mother during both pregnancies, the SI/TIBC of the infants were quite low. In the first pregnancy in which DF was administered in last months of gestation, a low level of serum ferritin was present in the newborn that was even lower at 3 months of age. In the second pregnancy, high normal, levels of ferritin were present in both twin newborns. Despite comparable gestational ages, hemoglobin levels were lower in the first pregnancy than the second. These studies indicate that very high maternal levels of SI/TIBS and serum ferritin were not associated with increased fetal SI/TIBC, which were, in fact, quite low. Because of the different fetal ferritin levels in the 2 pregnancies, it is possible that treatment of the mother with DF in the last weeks of pregnancy may have resulted in depletion of fetal iron stores.