Background & Objectives : Smoking is one of the major problems in the world today. It threatens people ’ s health. Pregnant women are no exception in this regard. Today, it is found that smoker women bear low birth weight babies, but the studies don ’ t offer clear findings about passive smoking in pregnancy and its effect on weight and height of newborns. This study is an attempt to determine the effects of passive smoking on the weight and height of the newborn babies.

  M ethods : This was a retrospective cohort study. We studied 100 pregnant mothers who were exposed to cigarette smoke and 100 others who were not. A checklist was completed in order to select those who could enter the study. A questionnaire was then filled out for both groups including the information related to the newborns ’ physical specifications.

  Results: This study showed that the average age of the mothers, their education, their husband ’ s education, number of pregnancies and the sex of babies born weren ’ t meaningfully different between the two groups. In the case group the mothers were exposed to cigarette smoke for 2.36 ± 2.28 hours on average and most of them (72%) were exposed to their husbands ’ cigarette smoke. The findings also indicated that difference in weight, height and head circumference among two groups ’ newborns were 11 grams, 0.15 cm and 0.02 cm respectively. The T-test indicated no significant difference between the two groups.

  Conclusion: The study showed that the newborns ’ of mothers exposed to the smoke had lower weigh, height and head circumference than the babies ’ of the control group subjects although the difference was not statistically significant.