Fundus Examination of 23,861 Newborns by Digital Imaging in Ningbo

Table 4

Factors affecting ROP in premature infants by univariate analysis.

Affecting factors		Total	N (%)	χ^2
Gender	Male	1583	338 (0.214)	0.123	0.726
	Female	1340	279 (0.208)
Delivery mode	Vaginal delivery	612	123 (0.201)	0.475	0.491
	Caesarean section	2311	494 (0.214)
Hypertension	Yes	321	72 (0.224)	0.378	0.539
	No	2602	545 (0.209)
Diabetes	Yes	358	79 (0.221)	0.225	0.635
	No	2565	538 (0.210)
Gestational age	26–28 + 6w	73	49 (0.671)	381.789	<0.001
	29–31 + 6w	819	305 (0.369)
	32–34 + 6w	1298	257 (0.188)
	35–36 + 6 w	733	6 (0.009)
Birth weight	＜1000 g	69	46 (0.681)	404.664	<0.001
	1000–2000 g	1187	423 (0.356)
	2000–3000 g	1453	147 (0.101)
	＞3000 g	214	0 (0.000)
Feeding methods	Human milk	1098	289 (0.263)	28.689	<0.001
	Formula	1825	328 (0.180)
Oxygen inhalation	Yes	1921	523 (0.272)	125.913	<0.001
	No	1002	94 (0.094)