Mean levels of HbF (%) remained significantly associated with BPD in the full statistical model after adjustment for mean PaO2 (kPa) and mean Hb (g/L): a 10% increase in HbF was associated with a decreased rate of BPD, OR of 0.72 (95% CI 0.54 to 0.97, p=0.032). Here, GSTM1 is linked to bronchopulmonary dysplasia.