With the incidence of diabetes rising in this country and throughout the world (an estimated 33.9% of the US population (1)), it is inevitable that as lactation consultants we will encounter mothers with diabetes, prediabetes, or a history of gestational diabetes. Does diabetes affect the course of lactation? Is there anything that we should be aware of as practitioners? The answer is a loud YES. For this post, our focus is going to be on whether diabetes affects breast milk production.

Breastfeeding rates and diabetes
Research has shown that mothers with type 1 diabetes are less likely to be breastfeeding at 2 and 6 months than mothers without diabetes (2). Other studies have noted that there is delayed lactogenesis in mothers with poorly controlled diabetes (3,4, 5). However, one study noted that this may be due in part to obesity, which is a common comorbidity for type 2 diabetes (3). It’s important to note that not ALL mothers with diabetes and/or obesity will automatically have milk supply issues. Nonetheless, if there is a low supply or delayed lactogenesis, it’s good practice to consider mom’s history of diabetes or insulin resistance.

Insulin Resistance
Of particular interest is the fact that insulin resistance in and of itself may affect milk supply, especially if in the setting of something like polycystic ovary syndrome (PCOS). Diana Cassar-Uhl, MPH, IBCLC, has a fantastic article outlining some of the research and recommendations for nursing mothers with varying degrees of insulin resistance. It’s a terrific read.
Signs of insulin resistance in mothers can range from difficulty losing weight, especially around the waist, to the signs of PCOS (oily skin, fertility issues, irregular menstruation, excess body hair) to the signs of pre-diabetes/diabetes (excessive thirst, frequent urination, etc.).

Individual care, complete picture.
Whether a mom has a definitive diagnosis of insulin resistance, diabetes, or PCOS, or it is only suspected, close contact with her doctor and diet recommendations from a registered dietitian are essential for mom’s health. It is unclear whether weight loss and blood sugar control will increase milk production if it is already affected. In short, as with many things lactation-related, nursing mothers need to receive individualized care, and diabetes and other forms of insulin-resistance need to be part of the overall picture of mom’s health to ensure breastfeeding success.

(1) Cdc.gov. (2017). National Diabetes Statistics Report. [online] Available at: https://www.cdc.gov/diabetes/pdfs/data/statistics/national-diabetes-statistics-report.pdf [Accessed 13 Feb. 2019].
(2) Leahy, K. (2016). Postpartum Care, Lactation, and Contraception in Diabetes. On the Cutting Edge, 37(4), pp.41-44. (3) Chapman, D. J. (2014). Risk Factors for Delayed Lactogenesis among Women with Gestational Diabetes Mellitus. Journal of Human Lactation, 30(2), 134–135.
(4) Neubauer, S., Ferris, A., Chase, C., Fanelli, J., Thompson, C., Lammi-Keefe, C., Clark, R., Jensen, R., Bendel, R. and Green, K. (1993). Delayed lactogenesis in women with insulin-dependent diabetes mellitus. The American Journal of Clinical Nutrition, 58(1), pp.54-60.
(5) Oza-Frank, R., Moreland, J. J., McNamara, K., Geraghty, S. R., & Keim, S. A. (2016). Early Lactation and Infant Feeding Practices Differ by Maternal Gestational Diabetes History. Journal of Human Lactation, 32(4), 658–665.