IGF1 and retinopathy of prematurity: Lastly, the analysis of IGF1 levels revealed significantly lower IGF1 levels in the Any ROP group both at the first collection (61.4 ± 35.6 ng/mL) and at the second collection (57.9 ± 32.8 ng/mL) compared to the No ROP group (91.6 ± 44.6 ng/mL and 90.1 ± 48.2 ng/mL, respectively), with p-values of 0.0004 and 0.0003 (Table 2).