A study of pregnant Punjabi, Indian women was carried out to establish whether or not there was a relationship between maternal HbA1 at term and birth weight of the baby. Measurements were made on the mother, placenta and baby. The regression of birth weight on placenta weight gave a correlation (r = 0.7, P less than 0.01, n = 59). No correlation was found between HbA1 and birth weight, birth weight corrected for placenta weight, or placenta weight. However, there was a weak but significant correlation between HbA1 and an adjusted placenta weight, expressed as a ratio Bwt'/Plwt', (r = 0.27, P less than 0.05, n = 56).