BIRTH-WEIGHT BELOW THE 10TH PERCENTILE - THE RELATIVE AND ATTRIBUTABLE RISKS OF MATERNAL TOBACCO CONSUMPTION AND OTHER FACTORS

Analysis of 7776 singleton births defined a cohort of babies with birt hweight below the 10th percentile after adjusting for gestational age and sex. The relative risk of a baby being small for gestational age i n respect to a number of factors, such as parental anthropometry, demo graphic factors, behavior patterns (tobacco, cannabis, alcohol, and ca ffeine consumption), maternal pathology and fetal abnormality, was cal culated. The highest relative risks are associated with severe antepar tum hemorrhage, severe pre-eclampsia, and severe fetal abnormality. As these are relatively rare events, a more accurate calculation of over all risk to the population as opposed to the individual can be obtaine d by studying the percent attributable risk of each of the factors. Th is demonstrates that maternal tobacco consumption is the major environ mental risk factor in our population.