Summary. Immune status during the third trimester of pregnancy was investigated in relation to maternal haemoglobin levels. The proportion of T and B lymphocytes showed a tendency to fall in anaemic women which was significant when haemoglobin levels were <8 g/dl. Immunoglobin G showed the opposite trend. There were no alterations in phytohaemag-glutinin-induced lymphocyte transformation in relation to haemoglobin concentration.