Lifestyle and sociodemographic risk factors for gastroschisis: a systematic review and meta-analysis

Background Gastroschisis is strongly associated with young maternal age. This association suggests the need for further investigations on non-genetic risk factors. Identifying these risk factors is a public health priority in order to develop prevention strategies aimed at reducing the prevalence and health consequences in offspring. Objective To systematically assess and quantitatively synthesise the available epidemiological studies to evaluate the association between non-genetic risk factors and gastroschisis. Methods Literature from PubMed, EMBASE and Scopus was searched for the period 1990–2018. Epidemiological studies reporting risk estimates between lifestyle and sociodemographic risk factors and gastroschisis were included. Two pairs of reviewers independently extracted information on study characteristics following Preferred Reporting Items for Systematic Reviews and Meta-Analyses and MOOSE (Meta-analysis Of Oservational Studies in Epidemiology) guidelines. Relative risk (RR) estimates were calculated across the studies and meta-analysis was performed using random-effects model. Results We identified 58 studies. Meta-analyses were conducted on 29 studies. Maternal smoking (RR 1.56, 95% CI 1.40 to 1.74), illicit drug use (RR 2.14, 95% CI 1.48 to 3.07) and alcohol consumption (RR 1.40, 95% CI 1.13 to 1.70) were associated with an increased risk of gastroschisis. A decreased risk among black mothers compared with non-Hispanic white mothers (RR 0.49, 95% CI 0.38 to 0.63) was found. For Hispanic mothers no association was observed. Conclusions Exposure to smoking, illicit drugs and alcohol during pregnancy is associated with an increased risk of gastroschisis. A significantly decreased risk for black mothers was observed. Further epidemiological studies to assess the potential role of other environmental factors are strongly recommended. PROSPERO registration number CRD42018104284.