Maternal pre-pregnancy obesity and the risk of macrosomia: a meta-analysis

Purpose The aim of our meta-analysis was to explore whether pre-pregnancy obesity is regarded as an important risk factor for predicting macrosomia or not. Methods Three databases were systematically reviewed and reference lists of relevant articles were checked. Meta-analysis of published cohort studies comparing whether pre-pregnancy obesity was associated with macrosomia and adjusting for potential confounding factors. Calculations of pooled estimates were conducted in random-effect model. Heterogeneity was tested by using Chi-square test and I-2 statistics. Publication bias was estimated from Egger's test (linear regression method) and Begg's test (rank correlation method). Results Sixteen cohort studies met the inclusion criteria. The meta-analysis showed that pre-pregnancy obesity was associated with macrosomia as an important risk factor. The adjusted odds ratio was 1.93, 95% CI (1.65, 2.27) in random-effect model, stratified analyses showed no differences regarding different quality grade, definition of macrosomia, location of study and number of confounding factors adjusted for. There was no indication of a publication bias either from the result of Egger's test or Begg's test. Conclusion Our findings indicated that pre-pregnancy obesity should be considered as an important risk factor for macrosomia. The effect of pre-pregnancy obesity on macrosomia need to be carefully assessed and monitored.