Women with lower calcitriol (1,25-dihydroxyvitamin D), the active form of vitamin D, were more likely to have an infant with congenital (OR 12.2 [95% CI 1.61–92.2] P = 0.02) and peri/postnatal (OR 9.84 [95% CI 2.63–36.8] P = 0.0007) infections in multivariate analyses, independent of maternal HIV viral load and CD4 count. This evidence concerns the gene CD4 and infection.