[Relationship between maternal serum glucose levels and human milk glucose concentrations]

To study the relationship between glucose levels in serum and glucose levels in maternal milk in healthy lactating women, and to discuss the factors influencing maternal milk glucose concentrations.

The samples and data were from the database for human milk composition in China between 2011 and 2013. A total of 184 lactating women with complete serum and breast milk glucose concentrations were included from 11 provinces across China. The human milk glucose was analyzed using high-performance anion exchange chromatography, and the serum glucose was analyzed with an automated biochemical analyzer. Using a general linear model, the relationship between maternal blood glucose levels and breast milk glucose concentrations was analyzed, along with the factors influencing breast milk glucose concentrations.

The average age of the study participants is(27.4±4.3) years, with 18(9.8%) having hypoglycemia, 164(89.1%) having normal blood glucose levels, and 2(1.1%) having hyperglycemia. The average maternal blood glucose level was(82.08±10.21) mg/dL. There was no significant difference in breast milk glucose concentrations between the hypoglycemia and normal blood glucose groups((26.90±8.84) mg/dL vs(24.76±10.11) mg/dL, P=0.39). There was no significant correlation observed between maternal blood glucose and breast milk glucose concentrations(r=-0.089, P=0.23, n=184). After stratifying by blood glucose levels and adjusting for factors such as lactation stage, parity, and outdoor activity time, no significant association was found as well(hypoglycemia: β=-0.341, P=0.21; normal blood glucose: β=-0.073, P=0.54). Multivariate analysis showed that the glucose concentration in late mature milk was significantly higher than that in early mature milk(29.08 mg/dL vs 23.63 mg/dL, P=0.02). Multiparous mothers had higher glucose concentrations in human milk compared to primiparous mothers(28.34 mg/dL vs 24.37 mg/dL, P<0.01), and there was a positive correlation between the duration of outdoor activities in the past 24 hours and glucose concentration in human milk(β=0.963, P<0.01).

Milk glucose concentrations was not significantly associated with maternal serum glucose concentrations in healthy lactating women. Lactation stage and parity were related to milk glucose concentrations, and outdoor activity time showed a positive correlation.