Table 4.

Regression analysis for risk of composite neonatal morbidity.

	aRR (95% CI)	p value
Dating method
1st trimester US	Reference
2nd trimester US	1.10 (0.98, 1.23)	.108
3rd trimester US	1.24 (1.04, 1.48)	.018
Delivery gestational age (weeks)
37 + 0 – 37 + 6	Reference
38 + 0 – 38 + 6	0.60 (0.52, 0.70)	<.001
39 + 0 – 39 + 6	0.46 (0.39, 0.54)	<.001
40 + 0 – 40 + 6	0.38 (0.30, 0.48)	<.001
> = 41 + 0	0.60 (0.46, 0.79)	.0002
Race
White	Reference
Non-White	1.16 (1.04, 1.30)	.009
Maternal age ≥35 years	1.07 (1.00, 1.02)	.111