Is HbA1c associated with birth weight? A multivariable analysis of Pakistani pregnant women

Aim Globally, one in seven infants is born with low birth weight and 3%–7% of infants are born with high birth weight, with the greatest burden noted in low‐ and middle‐income countries. This study investigated the association between maternal prenatal glucose regulation and birth weight and the moderating effect of fetal sex among Pakistani women. Methods Secondary data from a prospective longitudinal study of healthy pregnant women from Pakistan (N = 189) was used. Participants provided a blood sample (12–19 weeks' gestational age) for the assessment of HbA1c (%). Birth weight (g) was collected following delivery. Results Higher maternal HbA1c was associated with higher birth weight (b = 181.81, t[189] = 2.15, p = 0.03), which was moderated by fetal sex (b = −326.27, t[189] = −2.47, p = 0.02), after adjusting for gestational age at birth, ethnicity, and pregnancy weight. Among women carrying a male fetus, every 1% increase in HbA1c predicted a 182 g increase in birth weight (b = 181.81, t[189] = 2.15, p = 0.03). Conclusions Results extend research from high‐income countries and indicate that fetal sex may have implications for glucose regulation in early to mid‐pregnancy. Future research should examine sociocultural factors, which could elucidate potential mediating factors in the relation between HbA1c and birth weight in healthy pregnancies.