UC Irvine

Globally, one in seven infants is born with low birth weight while 3 to 7% of infants are both with high birth weight, with the greatest burden noted in low- and middle-income countries (LMICs). An unhealthy birth weight is associated with developmental difficulties and health problems both in early-life and throughout the life span. One aspect of a healthy pregnancy is maternal glucose regulation. Despite global disparities, the majority of research has been conducted in high-income countries, with most participants identifying as Caucasian or White. To address this gap in the literature, this study investigated whether average maternal glucose regulation during pregnancy (assessed via HbA1c) is associated with birth weight and whether fetal sex moderated this association. The analytic samples were comprised of adult healthy pregnant women in Pakistan (N = 111) and Kenya (N = 34). It was hypothesized that higher maternal glucose regulation during pregnancy would be associated with higher infant birth weight and that this association would be stronger for women carrying male versus female fetuses. Regression analyses suggested that higher glucose regulation was associated with higher birth weight infants in Pakistani women (b = 198.82, t[101] = 2.6, p = .01, 95% CI [49.35, 348.28]) and with lower birth weight infants in Kenyan women (b = 328.7, t[26] = -2.4, p = .02, 95% CI [-608.94, -48.48]), but only after adjusting for key covariates. Fetal sex did not significantly moderate these findings. These results suggest the importance of considering relevant cofounding variables, such as gestational age at birth, ethnicity, and pregnancy weight. Moreover, findings point to a need to study sociocultural factors, which could help explain the different direction of results for Pakistani and Kenyan women.