Gestational weight gain in obese women by class of obesity and select maternal/newborn outcomes: A systematic review

Background: Obesity and gestational weight gain impact maternal and fetal risks. Gestational weight gain guidelines are not stratified by severity of obesity. Aim: Conduct a systematic review of original research with sufficient information about gestational weight gain in obese women stratified by obesity class that could be compared to current Institute of Medicine guidelines. Evaluate variance in risk for selected outcomes of pregnancy with differing gestational weight gain in obese women by class of obesity. Methods: A keyword advanced search was conducted of English-language, peer-reviewed journal articles using 3 electronic databases, article reference lists and table of content notifications through January 2015. Data were synthesized to show changes in risk by prevalence. Findings: Ten articles met inclusion criteria. Outcomes assessed were large for gestational age, small for gestational age, and cesarean delivery. Results represent nearly 740,000 obese women from four different countries. Findings consistently demonstrated gestational weight gain varies by obesity class and most obese women gain more than recommended by Institute of Medicine guidelines. Obese women are at low risk for small for gestational age and high risk for large for gestational age and risk varies with class of obesity and gestational weight gain. Research suggests the lowest combined risk of selected outcomes with weight gain of 5-9. kg in women with class I obesity, 1 to less than 5. kg for class II obesity and no gestational weight gain for women with class III obesity. Conclusions: Gestational weight gain guidelines may need modification for severity of obesity.