Maternal smoking during pregnancy and offspring body mass index and overweight: a systematic review and meta-analysis

Abstract

The present study aimed to conduct a systematic review and meta-analysis to evaluate the evidence on the association of maternal smoking during pregnancy with offspring body composition in childhood, adolescence and adulthood. MEDLINE, Web of Science and LILACS databases were searched. Reference lists were also screened. We included original studies, conducted in humans, that assessed the association of maternal smoking during pregnancy with offspring body mass index (BMI) and overweight in childhood, adolescence and adulthood, published through May 1st, 2018. A meta-analysis was used to estimate pooled effect sizes. The systematic review included 64 studies, of which 37 evaluated the association of maternal smoking during pregnancy with overweight, 13 with BMI, and 14 evaluated both outcomes. Of these 64 studies, 95 measures of effect were extracted and included in the meta-analysis. We verified that the quality of evidence across studies regarding maternal smoking in pregnancy and overweight and BMI of offspring to be moderate and low, respectively. Most studies (44 studies) were classified as moderate risk bias. Heterogeneity among studies included was high and, in the random-effects pooled analysis, maternal smoking during pregnancy increased the odds of offspring overweight (OR: 1.43, 95%CI: 1.35; 1.52) and mean difference of BMI (β: 0.31, 95%CI: 0.23; 0.39). In conclusion, offspring of mothers who smoked during pregnancy have higher odds of overweight and mean difference of BMI, and these associations persisted into adulthood.

The association between secondhand smoke exposure and growth outcomes of children: A systematic literature review

“…A study by Braun et al 17 found stronger effects of tobacco smoke exposure as children become older. Our review is in line with a meta-analysis by Oken et al 13 on 14 articles (with 84563 children) and Magalhães et al 53 that children whose mothers smoked during the prenatal period were at an elevated risk of becoming overweight in childhood (OR=1.5 and OR=1.43, respectively). A meta-analysis by Qureshi et al 54 demonstrated the association between prenatal exposure to environmental tobacco smoke and childhood obesity with OR=1.905.…”

“…data not shown) or were not original research articles, these were also excluded 23 . As the effect of maternal smoking in the prenatal period on the growth of the offspring has been reviewed thoroughly elsewhere 13,14 , the aim of the present review was to emphasize SHS exposure from other people smoking (i.e. paternal smoking).…”

“…To date, limited information has been collated to illustrate the association between SHS exposure in non-smoking mothers during pregnancy and/or in children during postnatal life and the growth of children. Two review studies examined the association between SHS exposure and children growth outcomes, focusing on tobacco use of the mother during pregnancy 13,14 . Two other review articles explored the impact of SHS exposure on non-smoking pregnant women on anthropometric growth of children, focusing on the newborn baby 15,16 .…”

An index measuring adherence to New Zealand Infant Feeding Guidelines has convergent validity with maternal socio-demographic and health behaviours and with children’s body size

“…In this study, we opted for using Poisson regression with robust variance as an alternative to the odds ratio (OR), as OR can overestimate prevalence ratios and this overestimation increases as the prevalence of the outcome increases (30,31) . To select the independent variables to be tested in these models, an a priori causal model was used based on the published literature (12,13,(32)(33)(34)(35)(36)(37)(38) . This a priori model assumes that antenatal maternal socio-demographic and health behaviour variables influence both the IFI score and childhood adiposity and, therefore, need to be adjusted for in the models.…”

Teenage pregnancy

“…25 There is also increasing evidence for longer-term adverse health outcomes related to body mass index, with a recent meta-analysis finding that children of women who smoked during pregnancy had an increased risk of obesity in childhood when compared with children of women who did not smoke. 26 Smoking cessation in early pregnancy can almost eliminate these risks. It is recommended that smoking be addressed at every GP visit during pregnancy in view of its serious health impact.…”