Maternal weight gain and pattern of weight gain during pregnancy influence the ultimate outcome of pregnancy. Pregravid body mass index (BMI), maternal dietary intake, maternal height and age all determine the weight gain during pregnancy. The study was taken up with an objective to observe maternal weight gain and its pattern in pregnancy in women from an upper income group and to find out their association with pregnancy outcome. 180 normal primiparous pregnant Indian women (20–35 years) from an upper income group were recruited between the 10th and 14th weeks of pregnancy and were followed up throughout their pregnancy to record total and trimester-wise weight gain. Neonatal birth weights were recorded. The results showed that mothers with high pregravid BMI gained more weight during pregnancy than the recommended weight gain; in addition, weight gain in the first trimester was significantly correlated with birth weight of the neonates (P = 0.019). Significant correlation was found between weight gain in the third trimester and birth weight of the neonate irrespective of maternal BMI. The rate of weight gain was significantly correlated with neonatal birth weights irrespective of maternal pregravid BMI (P = 0.022) and as per its categories (P = 0.027). Thus, overall it can be concluded that adequate maternal nutrition before and during pregnancy is important for adequate weight gain by the mother and can result in better outcome of pregnancy. The rate of weight gain is also an important contributing factor.