Decreased birth weight and attainment of postnatal catch-up growth in offspring of rats exposed to cigarette smoke during gestation.

Pregnant rats were exposed to cigarette smoke daily for a 2-hour period throughout gestation and the body weights of offspring were monitored for 5 weeks postnatally. The average birth weight of the cigarette smoke exposed pups was significantly smaller compared to both pair-fed and ad libitum control groups. However, the body weights of the pups exposed to smoke were no longer significantly different from those in the pair-fed and ad libitum control groups at weeks 1 and 2 after birth, respectively. This study indicates that fetal growth retardation caused by exposure to cigarette smoke during pregnancy does not persist after birth.