Association of body mass index of HIV-1–infected pregnant women and infant birth weight, body mass index, length, and head circumference: the National Institute of Child Health and Human Development International Site Development Initiative Perinatal Stud

This study assessed the relationship between the body mass index (BMI) of HIV-1–infected women and their infants' perinatal outcomes. The study population was composed of women enrolled in the National Institute of Child Health and Human Development International Site Development Initiative Perinatal Study, with data allowing calculation of their BMI adjusted for length of gestation (adjBMI), who delivered singleton infants. Outcome variables included infant growth parameters at birth (weight, BMI, length, and head circumference) and gestational age. Among the 697 women from Argentina, the Bahamas, Brazil, and Mexico who were included in the analysis, adjBMI was classified as underweight for 109 (15.6%), as normal for 418 (60.0%), as overweight for 88 (12.6%), and as obese for 82 (11.8%). Median infant birth weight, BMI, length, and head circumference differed significantly according to maternal adjBMI (P ≤ .0002). Mothers who were underweight gave birth to infants with lower weight, lower BMI, shorter length, and smaller head circumference, whereas infants born to mothers who were of normal weight, overweight, and obese were of similar characteristics.