Objective: To investigate the effects of breastfeeding (BF) on metabolic-related outcomes in women with previous gestational diabetes mellitus. Methods: Databases, including PubMed, Embase, Cochrane Library, and Web of Science, were searched until March 5, 2020. Finally, 14 high-quality articles were included. Relative risk (RR) and weighted mean difference (WMD) with 95% confidence interval (CI) were pooled using Stata14.0 Software. Results: Subjects in the BF group had a lower incidence of diabetes (RR: 0.611, 95% CI: 0.452-0.826, p < 0.001) and lower fasting plasma glucose level (WMD: -4.762, 95% CI: -5.552 to -3.973, p < 0.001), fasting insulin level (WMD: -21.513, 95% CI: -37.594 to -5.431, p = 0.009), homeostasis model assessment of insulin resistance (HOMA-IR) (WMD: -1.107, 95% CI: -1.683 to -0.532, p < 0.001), and triglyceride level (WMD: -33.951, 95% CI: -50.714 to -17.189, p < 0.001) than those in the non-BF group. The high-density lipoprotein level (WMD: 3.855, 95% CI: 2.629-5.081, p < 0.001), low-density lipoprotein level (WMD: 4.223, 95% CI: 0.6712-7.774, p = 0.020), and insulin sensitivity index (WMD: 1.503, 95% CI: 0.857-2.160, p < 0.001) in the BF group were higher than that in the non-BF group. No difference was found in the 2-hour postprandial blood glucose (WMD: -3.804, 95% CI: -8.237 to 0.630, p = 0.093), incidence of prediabetes mellitus (RR: 0.870, 95% CI: 0.750-1.009, p = 0.065), or cholesterol level (WMD: 1.377, 95% CI: -8.178 to 10.931, p = 0.778) between the two groups. Conclusion: BF may improve several metabolic markers and decrease the risk of developing diabetes.
Keywords: breastfeeding; diabetes; gestational diabetes mellitus; metabolic-related outcomes.