A comparison of the effects of prenatal exposure to tobacco, alcohol, cannabis and caffeine on birth size and subsequent growth.

Maternal use of cigarettes, alcohol, cannabis, and caffeine was established for four time periods; prepregnancy, first trimester, third trimester and average use over pregnancy. The relationship between such usage and growth parameters of offspring followed up from birth to 12 and 24 months of age were examined. Of the soft drugs used, nicotine had the most pronounced effect. After adjustment for other relevant variables, nicotine use prior to and during pregnancy was negatively related to weight and head circumference at birth. Furthermore, third trimester nicotine use was a stronger predictor of decreased weight and head circumference at birth than was first trimester use. The results obtained are consistent with ponderal index (PI) literature suggesting a recovery of growth retardation in infants with a lowered PI. Average consumption of greater than one ounce of absolute alcohol per day was negatively related to birth weight and length. Neither cannabis nor caffeine use had a significant negative effect on any growth parameter.