Table 3

Percentage and OR (and 95% CI)^* for adverse birth outcomes for ethnic minority women compared with white women, by migrant status; and OR of migrants compared with US-born women, by ethnic group

Outcome	Ethnic group	Migrants		US-born		Migrants versus US-born†
LBW			N=6 487 938		N=11 702 432
		LBW %	OR (95% CI)	LBW %	OR (95% CI)*	OR (95% CI)*
	Whites	4.0	1.00	4.6	1.00	0.87 (0.66 to 1.16)
	Asians	5.4	1.37 (1.05 to 1.79)	5.8	1.28 (1.02 to 1.60)	0.94 (0.76 to 1.14)
	Blacks	8.2	2.14 (1.61 to 2.41)	12.3	2.94 (2.36 to 3.67)	0.64 (0.51 to 0.79)
	Hispanics	4.4	1.10 (0.85 to 1.43)	5.6	1.26 (1.02 to 1.55)	0.76 (0.65 to 0.89)

PTB			N=4 009 158		N=8 587 564
		PTB %	OR (95% CI)	PTB %	OR (95% CI)	OR (95% CI)
	Whites	7.9	1.00	9.5	1.00	0.82 (0.66 to 1.01)
	Asians	11.1	1.44 (1.15 to 1.81)	10.2	1.08 (0.88 to 1.33)	1.09 (0.88 to 1.35)
	Blacks	12.3	1.62 (1.30 to 2.03)	16.6	1.89 (1.64 to 2.19)	0.70 (0.62 to 0.80)
	Hispanics	10.5	1.35 (1.10 to 1.66)	11.6	1.24 (1.07 to 1.44)	0.89 (0.79 to 1.00)

LBW, low birth weight; OR, odds ratio; PTB, preterm birth.
↵* Obtained with the full three-level model including random effects (subgroup and studies), and fixed effects (migrant status, race/ethnicity, migrant status × race/ethnicity and infant's year of birth).
↵† US-born is the reference group.