Abstract

Background: Smoking is preventable factor for pregnancy outcomes such as low birth weight (LBW). In this study, we assessed the effects of smoking cessation in pregnancy period on the birth weight in Randomized Controlled Trial studies (RCTs). Methods: International databases of Pub Med, Scopus, and Web of Science, by the MeSH heading and/or additional terms, were searched to assess relevant studies in systematic possess. I-2 statistics was used to assess of heterogeneity. Pooled effects size was obtained by random effects model. Meta-regression was used to explore of heterogeneity using Stata software version 12 (Stata Corp, College Station, TX). Results: A total 16 RCTs, 6192 women were enrolled to assess of smoking cessation in pregnancy period on the birth weight. Relative risk (RR) of not smoking at the end of pregnancy in intervention group was 2.47 (95 CI: 1.73-3.20). The odds ratio (OR) for effect of smoking cessation on LBW was 0.65 (95 CI: 0.42-0.88) and standardized mean difference (SMD) was significantly increased in the intervention group, 0.28 (95 CI: 0.05-0.50). Conclusions: Results of this study approve results of previous RCTs that smoking cessation in pregnancy is a good practical action to prevention of LBW in infants.