Study of serum immunoglobulins in normal pregnancy.

Suppression of maternal immune response may be one of the factors contributing to continuation of pregnancy, a state in which the foetus exists as a well tolerated homograft. Studies on serum immunoglobulin levels in pregnancy show varying results. In this study serum immunoglobulin levels of Ig G, Ig A and Ig M were estimated in 75 normal pregnant women, 25 in each trimester. These were compared with a control group of 25 healthy women. A graded significant decrease in Ig G levels was observed throughout the pregnancy. Ig A levels decreased during the first and second trimester of pregnancy. A significant increase in Ig M levels from the first to third trimester was observed.