The effect of pre-pregnancy body mass index on the risk of gestational diabetes mellitus: A systematic review and Dose-Response Meta-Analysis

Background: Gestational diabetes mellitus (GDM) is the most common metabolic disorder during pregnancy and high pre-pregnancy BMI is strongly associated with GDM. This study aims to investigate the effect of pre-pregnancy body mass index on the risk of GDM. Methods: In this study, five electronic databases including Medline (PubMed), Scopus, Embase, Web of Science and Google Scholar were searched for literature published up to 1 January 2018. The pooled effect analysis was performed using fixed and random-effect models. The twostage random-effects meta-analysis was performed for a dose-response relationship between BMI (dose) and GDM. Also, studies that they treated the BMI as a continuous variable wereanalyzed. Results: Up to 2018, thirty-three observational studies with a total of 966852 samples and 40721 patients with GDM were included in the present study. The pooled estimate of GDM risk in pregnant women using adjusted OR was 0.68, 2.01, and 3.98 and using adjusted RR was 0.34,1.52, and 2.24 for underweight, overweight and obesity, respectively. The trend for risk of GDM indicates a significant linear increase along with BMI (dose) increase in pregnant women. So that, in both crude and adjusted OR/RR models, the risk of GDM increase 4% (effect=1.04; 95% CI: 1.03-1.05) with an increase in a unit of BMI (dose). In addition, using the random effect model, the risk of GDM based on crude risk increase 19% and based on the adjusted risk increase 14% with an increase in a unit of BMI Conclusions: Dose-response association between pre-pregnancy BMI and GDM is an important finding that can reinforce the scientific background for vigorous public health interventions for control of pre-pregnancy BMI as well as the weight gain during pregnancy. In addition, the screening program of GDM for those women who are obese need to be reinforced

The effect of pre-pregnancy body mass index on the risk of gestational diabetes mellitus: A systematic review and Dose-Response Meta-Analysis Keywords:

Pre-Pregnancy , Body Mass Index , Risk , Gestational Diabetes Mellitus