Is there an association between maternal smoking and oral clefts?

Abstract

Data sourcesCochrane, PubMed and Ovid Medline. A search timeline of January 1966 to May 2015 was used and language was restricted to English.Study selectionCase-control and cohort studies relating to oral clefts, with information on maternal active smoking, before and after conception, excluding paternal smoking and exposure to environmental tobacco smoke.Data extraction and synthesisTwo authors extracted data independently. Both Begg's and Egger's funnel plots were used to assess publication bias. Sensitivity analysis was performed to assess impact of the different study types and chi-squared and P values were determined by SPSS software. Studies with missing data were excluded from the meta-analysis.ResultsA statistically significant association was found between maternal active smoking and CL +/- P (odds ratio [OR] 1.368; 95% confidence interval [CI] 1.259-1.486) as well as CP (OR 1.241; 95% CI 1.117-1.378). Half the studies showed positive dose-response effect for each subgroup (test for linear trend, P < .05).ConclusionsWomen who smoke during pregnancy have a moderate risk of having a child with a CL +/- P or CP. A dose-response effect between maternal smoking and clefts was not established.

Maternal consumption of caffeine and second-hand tobacco smoke as risk factors for the development of oral clefts

“… 16 Both coffee ingestion 21 and exposure to second-hand tobacco smoke 22 have been shown to increase the plasma concentration of homocysteine. Additionally, these factors have been associated with an elevated risk of spontaneous abortions, chromosomal anomalies, multiple congenital aberrations, 23 and notably, low birth weight. 24 …”

Smoking and Tobacco Use: Ill Effects on Reproductive, Maternal, Newborn, Child Health, and Adolescent (RMNCHA) Program—A Review

“…There is an increased risk of congenital defects in the offspring of smokers. 53 The most commonly reported birth defects include orofacial clefts (cleft lip or cleft palate), [54][55][56] neural tube defects (defects of the defects of the brain, spine, or spinal cord), 57,58 cardiovascular/heart defects, musculoskeletal defects, limb reduction defects, missing/extra digits, clubfoot, craniosynostosis (fused skull bones that may affect brain growth), facial defects, eye defects, gastrointestinal defects, gastroschisis, anal atresia, hernia, and undescended testes. 59 A meta-analysis of 23 articles showed a higher risk of neural tube defects in neonateswhen mothers smoked (OR: 1.05), and this further increased with exposure to passive smoking.…”

Maternal Cigarette Smoking and Cleft Lip and Palate: A Systematic Review and Meta-Analysis

“…Three previous meta-analyses have demonstrated weak to moderate links between maternal smoking and CL/P (Wyszynski et al, 1997; Julian Little et al, 2004; Xuan et al, 2016). While previous systematic reviews have been comprehensive, the included studies were not assessed for their quality and this might have compromised the validity of the findings (Crossan and Duane, 2018). Potential sources of bias in the primary studies include no adjustment for confounders, inappropriate control groups and recall bias.…”