TY - JOUR T1 - Low fraction of fetal haemoglobin is associated with retinopathy of prematurity in the very preterm infant JF - British Journal of Ophthalmology JO - Br J Ophthalmol DO - 10.1136/bjophthalmol-2020-318293 SP - bjophthalmol-2020-318293 AU - William Hellström AU - Tobias Martinsson AU - Eva Morsing AU - Lotta Gränse AU - David Ley AU - Ann Hellström Y1 - 2021/02/05 UR - http://bjo.bmj.com/content/early/2021/02/05/bjophthalmol-2020-318293.abstract N2 - Background Blood loss and adult blood transfusions are common during the neonatal period in preterm infants. The objective of the study was to clarify if degree of loss of fetal haemoglobin (HbF) was associated with later retinopathy of prematurity (ROP).Methods Retrospective observational cohort study. In total, 452 infants born <30 gestational weeks at a tertiary level neonatal intensive care unit in Sweden in 2009–2015 were included, 385 of whom had final ROP outcome. Mean fractions of HbF (%) during the first postnatal week were calculated from 11 861 arterial blood gas analyses. The relationship between fractions of HbF (%) and ROP was evaluated.Results The mean (SD) gestational age (GA) at birth was 26.4 (1.8) weeks. In total, 104 (27 %) infants developed ROP. Higher fraction of HbF (%) was associated with a lower prevalence of ROP, OR by a 10% increase 0.83 (95% CI: 0.71 to 0.97; p=0.019), following adjustment for GA at birth, small for GA and sex. Infants with HbF (%) in the lowest quartile had OR of 22.0 (95% CI: 8.1 to 59.2; p<0.001) for ROP development compared with those in the highest quartile. The predictive ability (area under the curve) of HbF (%) in the full model during the first week was 0.849 for ROP.Conclusions Early low fraction of HbF is independently associated with abnormal retinal neurovascular development in the very preterm infant. The potential benefit of minimising blood loss on development of ROP will be investigated in a multicenter randomised trial (NCT04239690). ER -