Immunoglobulin levels in mothers and their new-born in two socio-economic groups

Levels of the three major immunoglobulins IgG, A and M were measured in paired maternal and cord sera from two income groups of population at the time of delivery. Levels of IgG were significantly higher in the maternal sera obtained from low income group. A close correlation was seen between cord IgG and birth weight upto 2.3 kg. 4% and 25% of cord sera had levels of IgA and IgM greater than 2 S.D. of mean levels indicating possibility of intrauterine infection. The possibility of placental leak was negated by the observation that the levels of these two Igs were also higher in corresponding maternal sera. Low degree of correlation between maternal or cord immunoglobulins of all classes and birth weight suggested that intrauterine infection has relatively minor role in influencing the birth weight of the neonate.