Background and Aims Previous studies showed that switchover from fetal (HbF) to adult (HbA) haemoglobin occurs in relation to postmenstrual age (PMA).
Aims To assess HbF levels at 36 weeks PMA in preterm infants born between 24 and 31 completed weeks, to determine their association with bronchopulmonary dysplasia (BPD), sepsis and packed-red-blood-cells (PRBC) transfusions.
Methods A retrospective cohort study of 130 preterm infants was performed.HbF determinations were obtained from the routine capillary blood gasses using ABL-800-flex (Radiometer Copenhagen) and results were reported as percentage of total Hb. Associations of HbF levels and clinical variables were tested by t-test and multiple regression analysis.
Results Infants were born at a mean gestational age of 28.1 weeks (range 24–31.5 weeks), with a mean birth weight of 995 g (range 380–1965 g); 45 of them (34.6%) had BPD, 36 (27.7%) were affected by sepsis and 76 (58.5%) received PRBC-transfusions (mean transfusion rate 2.5). At the univariate analysis HbF was significantly lower in infants with BPD (54.3%±21.2% vs 62.9%±18%; p=0.03), in those with sepsis (49%±18.7% vs 63%±18.6%; p=0.002) and in infants who received PRBC-transfusions (48.8%±14.6% vs 74.6%±17.2%; p<0,001). By multiple regression analysis, lower HbF levels were significantly associated to greater number of transfusions (p<0.001), previous occurrence of sepsis (p=0.01) and BPD (p=0.05).
Conclusions PRBC-transfusions, sepsis and BPD are associated with lower HbF levels at 36 weeks PMA. Information on postnatal changes of HbF level and its related factors will help better understanding of oxygen transport in selected complications of prematurity.