Elucidation of Breast Milk Composition and Structure Over the First Year of Lactation: UC Davis Lactation Study

This study's objectives include: 1) develop a better understanding of the composition and structures of breast milk over the early stages of lactation with specific emphasis on the glycans and lipids; 2) how glycan diversity relates to maternal and infant gut microbiota with an emphasis on bifidobacteria species; 3)how milk composition and structure relate to maternal health and diet.

These samples will be analyzed using comprehensive gas and liquid chromatographic methods, nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS); and next generation sequencing, terminal restriction fragment length polymorphism and quantitative polymerase chain reaction.

There are several cohorts to the main study.

Gestational Diabetes Mellitus Cohort. The aim of this study is to investigate the differences between milk composition, infant and maternal gut microbiota from women with and without gestational diabetes mellitus or type 2 diabetes vs. controls.

Fresh Milk Study. The aim of this study is to elucidate the relationship between the expression of glycan metabolizing genes of mammary epithelial cells and levels of milk glycans.

RNA Study. The aim of this study is to compare the RNA of milk fat globule membrane crescents in human milk against epithelial expression profiles in non-human primate milk.

Skin Study. The aim of this study is to provide skin samples from healthy term infants to act as the control group for a different study with preterm infants.

Breast Milk, Gut Microbiome, and Immunity (BMMI) Project. The aim of this study is to provide healthy control samples for the BMMI project. The BMMI project is a multi-investigative project designed to elucidate how maternal nutrient status, and milk composition and structure influence infant gut microbiome from participants in developing countries.

Inclusion criteria

• Pregnant women 18 years and older who plan to breastfeed for at least 6 months
• Women who are in good health
• Women with or without diagnosis of gestational diabetes mellitus, or type 2 diabetes mellitus or impaired glucose tolerance

Exclusion criteria

• Women who do not plan to breastfeed for at least 6 months
• Women who give birth to pre-term infants
• Women who smoke, either currently or 1 year before becoming pregnant
• Women who have chronic medical conditions or communicable diseases
• Women who take metabolic altering drugs such as corticosteroids or thyroid medication