Insulin

PMID: 30000050

Abstract:

Mothers with diabetes using insulin may nurse their infants.[1][1] Exogenous insulin is excreted into breastmilk, including newer biosynthetic insulins (e.g., aspart, glargine glulisine, lispro). Insulin is a normal component of breastmilk and may decrease the risk of type 1 diabetes in breastfed infants.[2-4] Pasteurization of milk by the Holder method reduces the concentration of insulin by about half.[5]
Insulin requirements are reduced postpartum in women with type 1 diabetes.[1,6] In one study, insulin requirements were lower than prepregnancy dosage only during the first week postpartum: 54% of prepregnancy dosage on day 2 and 73% on day 3 postpartum. On day 7 postpartum, insulin dosage returned to prepregnancy requirements.[7] Another study found that dosage requirements did not return to normal for up to 6 weeks in some mothers.[8] A third study found that at 4 months postpartum, patients with type 1 diabetes who exclusively breastfed had an average of 13% lower (range -52% to +40%) insulin requirement than their prepregnancy requirement.[9] A retrospective case-control study found a 34% decrease in postpartum insulin requirement compare to preconception values. There was a nonsignificant trend towards lower requirements in exclusively breastfeeding mothers compared to partial or full formula feeding.[6] A small study found that mothers on insulin pumps were found to have an average basal insulin rates 14% lower and carbohydrate-to-insulin ratios were 10% higher than pre-pregnancy settings.[10] Breastfeeding appears to improve glucose postpartum glucose tolerance in mothers with gestational diabetes mellitus and in normal women.[11-13]
A small, well-controlled study of women with type 1 diabetes mellitus using continuous subcutaneous insulin found that the average basal insulin requirement in women with type 1 diabetes who breastfed was 0.21 units/kg daily and the total insulin requirement was 0.56 units/kg daily. In similar women who did not breastfeed, the basal insulin requirement was 0.33 units/kg daily and the total insulin requirement was 0.75 units/kg daily. The 36% lower basal insulin requirement was thought to be caused by glucose use for milk production.[14]
Lactation onset occurs later in patients with type 1 diabetes than in women without diabetes, with a greater delay in mothers with poor glucose control.[7,15] Mothers with type 1 diabetes also discontinue nursing at a higher rate during the first week postpartum.[16-18] Women with any form of diabetes during pregnancy had more problems with low milk supply than women without diabetes.[19] Once established, lactation persists as long in mothers with diabetes as in mothers without diabetes.[15,20] However, as in women without diabetes, smoking has a strong negative impact on lactation among mothers with type 1 diabetes.[9,21] Other factors that have been identified as causes of shorter duration of breastfeeding among type 1 diabetic patients are more frequent caesarean sections and earlier delivery.[22] Among patients with gestational diabetes, those treated with insulin have a delayed onset of lactogenesis II compared to those not treated with insulin.[23]

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP11061680-A	Insulin human		11061-68-0	Price