Grant: Travel Awards - Institute Community Support

OBJECTIVE: Which diet is the best for the management of blood sugars in mothers during pregnancy is still unclear. We conducted a systematic review and network meta-analysis in pregnant women to compare the effects of different diets on diabetes risk factors (fasting blood glucose [FBG] and insulin [FBI], glycated hemoglobin [HbA1c], Homeostatic Model Assessment- Insulin Resistance [HOMA-IR]). A network meta-analysis is a useful evidence synthesis tool that can pool studies together to determine the "average" effect of one diet compared to another and also rank diets to assess which is the best. METHODS: MEDLINE, EMBASE, and COCHRANE (to April 2014) were used to identify randomized trials of diets on diabetes risk factors at 4-weeks or longer during pregnancy. Two independent reviewers recorded relevant study characteristics and data. A network meta-analysis was conducted to compare the effects of diets on FBG, whereas individual trial comparisons were presented for FBI, HbA1c, and HOMA-IR owning to a lack of trials. Study quality was assessed using the Cochrane's Risk of Bias Tool and the quality of evidence for each outcome was assessed using the GRADE approach. RESULTS: Thirteen studies met our inclusion criteria (n= 1838 participants). Only a weight management diet compared to no dietary advice showed a meaningful reduction on FBG (-0.48 mmol/L [95% credible interval -0.87, -0.03]). General healthy dietary advice compared to no dietary advice given during pregnancy demonstrated statistically significant reductions in FBI, HbA1c, and HOMA-IR (p< 0.05). CONCLUSIONS: A weight management diet compared to no dietary advice demonstrated a meaningful FBG reduction. Healthy dietary advice compared to no dietary advice also found a significant improvement on FBI, HbA1c, and HOMA-IR. To confirm these results, larger, longer, higher quality randomized trials are needed. SIGNIFICANCE: Healthy diets may be an effective strategy to improve blood sugars in pregnant women