Maternal smoking status during pregnancy and low birth weight in offspring: Systematic review and meta-analysis of 55 cohort studies published from 1986 to 2020

Hong-Kun Di, Yong Gan, Kai Lu, Chao Wang, Yi Zhu, Xin Meng, Wen-Qi Xia, Min-Zhi Xu, Jing Feng, Qing-Feng Tian, Yan He, Zhi-Qiang Nie, Jun-An Liu, Fu-Jian Song, Zu-Xun Lu

Research output: Contribution to journalReview articlepeer-review

Abstract

Background: Maternal smoking during pregnancy may be associated with low birth weight (LBW) in offspring and global risk estimates have not been summarized previously. We aimed to systematically explore evidence regarding maternal smoking and the LBW risk in offspring globally and examine possible causes of heterogeneity across relevant studies.

Methods: Comprehensive search of PubMed, Ovid Embase, Ovid Medline (R), and Web of science from inception until October 2021 was carried out. A random-effects meta-analysis was used to estimate the pooled odds ratio (OR) and corresponding 95% confidence interval (CI). Restricted cubic spline analysis with four knots was used to further examine the dose-response relationship.

Results: Literature searches yielded 4,940 articles, of which 53 met inclusion criteria (comprising 55 independent studies). Maternal smoking during pregnancy was significantly associated with the risk of LBW in offspring (OR=1.89 , 95% CI=1.80-1.98). Furthermore, an obvious dose–response relationship between the amount of cigarettes daily smoked in pregnancy and the risk of LBW in offspring was observed. The results of subgroup analyses indicated that the risk of maternal smoking on LBW was larger in more recently conducted studies (P = .020) and longer period of active smoking during pregnancy (P = .002). No evidence of publication bias was found.

Conclusions: In summary, maternal smoking in pregnancy was significantly associated with a aternal smoking in pregnancy was significantly associated with a higher risk of LBW in offspring on a global scale. The risk of maternal smoking on infant higher risk of LBW in offspring on a global scale. The risk of maternal smoking on infant LBWLBW seems to be increasing over time, and was higher with seems to be increasing over time, and was higher with longer smoking duration longer smoking duration throughout pregnancy and more cigarettes smoked daily. throughout pregnancy and more cigarettes smoked daily.
Original languageEnglish
Pages (from-to)176-185
Number of pages10
JournalWorld Journal of Pediatrics
Volume18
Issue number3
Early online date28 Jan 2022
DOIs
Publication statusPublished - Mar 2022

Keywords

  • Low birth weight
  • Maternal smoking
  • Meta-analysis
  • Pregnancy

Cite this