Independent effect of maternal birth weight on infant birth weight

The relationship between the birth weights of the mother and her infant was evaluated in a sample of 106 women consecutively delivered of a single live birth. Women were included in the study if their birth weight was available in hospital files or from another reliable source. Women that were themselves a twin or had diseases complicated the course of the pregnancy were excluded. A positive significant correlation was found between mother and infant birth weights (r = 0.29, p = 0.003). This correlation remained significant (partial r = 0.22, p = 0.039) after adjusting for other covariables such as the mother's age, height, education, whether the pregnancy was planned, number of cigarettes smoked daily during pregnancy, month of first antenatal visit and number of visits, weight at end-pregnancy, gestational age and sex of the newborn. In the multiple linear regression model, mother's birth weight explained 3% of the variation observed in infant birthweight. A weaker crude correlation was also found between mothers' birth weight and gestational age (r = 0.19, p = 0.06). This study shows that maternal birth weight is an independent predictor of infant birth weight, and confirms previous findings suggesting that this maternal factor has a stronger effect on the birth weight than on the gestational age of the newborn.