Among thalassaemia traits during stress, like pregnancy refractory microcytic hypochromic anaemia occurs. Differences of mean Hb% are statistically significant in both the groups through out the pregnancy and the differences have increased as pregnancy advances.During pregnancy, maternal hemoglobin levels may fall to some extent but severe anaemia does not result. Thalassaemia trait does not have any significant influence over estimated fetal weight or liquor volume or perinatal outcome in respect to hemoglobin of baby, birth weight, one minute Apgar score.