Maternal systemic inflammation during pregnancy may restrict embryo-fetal growth, but the extent of this effect remains poorly established in undernourished populations. In a cohort of 653 maternal-newborn dyads participating in a multi-armed, micronutrient supplementation trial in southern Nepal, we investigated associations between maternal inflammation, assessed by serum α1-acid glycoprotein and C-reactive protein, in the first and third trimesters of pregnancy, and newborn weight, length and head and chest circumferences. Median (IQR) maternal concentrations in α1-acid glycoprotein and C-reactive protein in the first and third trimesters were 0.65 (0.53-0.76) and 0.40 (0.33-0.50) g/l, and 0.56 (0.25-1.54) and 1.07 (0.43-2.32) mg/l, respectively. α1-acid glycoprotein was inversely associated with birth size: weight, length, head circumference and chest circumference were lower by 116 g (P = 2.3 × 10-6), and 0.45 (P = 3.1 × 10-5), 0.18 (P = 0.0191) and 0.48 (P = 1.7 × 10-7) cm, respectively, per 50% increase in α1-acid glycoprotein averaged across both trimesters. Adjustment for maternal age, parity, gestational age, nutritional and socio-economic status and daily micronutrient supplementation failed to alter any association. Serum C-reactive protein concentration was largely unassociated with newborn size. In rural Nepal, birth size was inversely associated with low-grade, chronic inflammation during pregnancy as indicated by serum α1-acid glycoprotein.
Keywords: Fetal growth restriction; laboratory tests; low birth weight; maternal inflammation; orosomucoid.