TABLE 2—

Overall Effects of African Ancestry Indicators on Low Birth Weight and Preterm Birth: Brazil, 1995–2009

	Unadjusted		Adjusted
Total Model Sample	LBW, OR (95% CI)	PTB, OR (95% CI)	LBW, OR (95% CI)	PTB, OR (95% CI)
African-only ancestrya (n = 2852)	1.56** (1.20, 2.03)	1.30* (1.05, 1.61)	1.28 (0.99, 1.65)	1.10 (0.97, 1.58)
African–non-European mixed ancestrya (n = 3539)	1.66** (1.39, 2.00)	1.39** (1.16, 1.65)	1.10 (0.76, 1.42)	1.09 (0.92, 1.32)
African–European mixed ancestrya (n = 6608)	1.58** (1.27, 1.97)	1.28** (1.11, 1.48)	1.02 (0.75, 1.22)	1.01 (0.89, 1.30)

Note. CI = confidence interval; LBW = low birth weight; OR = odds ratio; PTB = preterm birth. The table shows ORs for the effects of ethnic ancestry on low birth weight and preterm birth with 95% CIs. We estimated a separate model for each African ancestry group relative to European-only ancestry. The model sample size is the sum of each African ancestry group sample and that of the European-only ancestry group and is the same for all adjusted and unadjusted models for LBW and PTB for a certain ancestry comparison. The adjusted model included as covariates all the explanatory variables listed in Table 1.

^aReference is European-only ancestry.

*P < .05; **P < .01.