Abstract and Introduction
Women with gestational diabetes mellitus (GDM) have a high risk of developing postpartum type 2 diabetes. Strategies to prevent postpartum type 2 diabetes are important to reduce the epidemic of diabetes and its societal impact. Breastfeeding was reported to improve early postpartum glucose tolerance and reduce the subsequent risk of type 2 diabetes. To investigate whether breastfeeding influences short- and long-term postpartum diabetes outcomes, women with GDM (n = 304) participating in the prospective German GDM study were followed from delivery for up to 19 years postpartum for diabetes development. All participants were recruited between 1989 and 1999. Postpartum diabetes developed in 147 women and was dependent on the treatment received during pregnancy (insulin vs. diet), BMI, and presence/absence of islet autoantibodies. Among islet autoantibody-negative women, breastfeeding was associated with median time to diabetes of 12.3 years compared with 2.3 years in women who did not breastfeed. The lowest postpartum diabetes risk was observed in women who breastfed for >3 months. On the basis of these results, we recommend that breastfeeding should be encouraged among these women because it offers a safe and feasible low-cost intervention to reduce the risk of subsequent diabetes in this high-risk population.
Gestational diabetes mellitus (GDM) occurs in around 4% of pregnancies and is defined as glucose intolerance with an onset or first diagnosis during pregnancy. GDM is known to increase the risk for postpartum type 2 diabetes. Of potential relevance for the protection against postpartum diabetes, an analysis of large cohort studies in the U.S. found that the duration of lactation was inversely associated with the incidence of type 2 diabetes.[3–5] The risk reductions were particularly marked when breastfeeding was continued for 1 to 2 years or ≥2 years. However, women with GDM are less likely to breastfeed and, if they do, breastfeeding usually is continued for a shorter duration than among women without diabetes.[6–10] Nevertheless, women with GDM who do breastfeed have improved lipid and glucose metabolism during the first 3 months after birth.[11–13] These findings suggest that breastfeeding may not only have a short-term effect on postpartum glucose tolerance, as previously shown[11–13] but may also delay the long-term development of type 2 diabetes among women with GDM. Nevertheless, few studies have assessed these possibilities.[3,2]
The prospective German GDM study has followed patients with GDM from delivery for up to 19 years postpartum to determine the risk of developing diabetes and to identify factors that modify long-term risk for postpartum diabetes. Here, we examined the risk of postpartum diabetes and tested the hypothesis that breastfeeding protects against postpartum type 2 diabetes in women with GDM.
Diabetes. 2012;61(12):3167-3171. © 2012 American Diabetes Association, Inc.