Table 1.

The rate and stage of ROP in infants with gestational age equal or less than 37 weeks

ROP	Right Eye	Left Eye
	Frequency (%)	Frequency (%)
No ROP	914 (45.9)	904 (45.4)
Immature retina (avascular area)	585 (29.4)	566 (28.4)
Prethreshold Type 2 and less severe forms of ROP	322 (16.2)	349 (17.5)
Pre-threshold ROP Type 1	60 (3)	56 (2.8)
Threshold ROP	75 (3.8)	76 (3.8)
Stage 4a	11 (0.6)	14 (0.7)
Stage 5	21 (1.1)	22 (1.1)
Autoregressed ROP with unfavorable outcome	2 (0.1)	3 (0.2)
ROP, retinopathy of prematurity