IMMUNOGLOBULIN G LEVELS IN NORMAL, PRETERM AND LOW BIRTH WEIGHT(LBW) NEWBORNS- A COMPARATIVE STUDY

Immunoglobulin G (IgG) is the principal antibody transferred from mother to fetus through the placenta and provides essential passive immunity during early neonatal life.The efficiency of this transfer is largely dependent on gestational age and fetal growth, making preterm and low birth weight (LBW) newborns more vulnerable to infections.This prospective observational study was conducted in the Department of Physiology, Hi-Tech Medical College & Hospital, Bhubaneswar, from February 2024 to August 2025, to estimate and compare serum IgG levels among normal full-term, preterm, and LBW newborns and to assess their correlation with gestational age and birth weight.A total of 99 newborns were enrolled and divided equally into three groups: full-term normal, preterm, and LBW.Cord blood samples were collected at birth, and serum IgG levels were measured using the ELISA method.The mean serum IgG concentration was significantly higher in full-term newborns (820 ± 45 mg/dL) compared to preterm (620 ± 52 mg/dL) and LBW neonates (610 ± 49 mg/dL) (p < 0.05).A strong positive correlation was observed between gestational age and IgG levels (r = +0.78),while birth weight showed a moderate positive correlation (r = +0.64).The findings indicate that gestational maturity and adequate intrauterine growth play a critical role in effective transplacental IgG transfer, and reduced IgG levels in preterm and LBW newborns may contribute to their increased susceptibility to infections during early life.