MILK Study


Mothers and Infants LinKed for Healthy Growth

Congratulations Mom and Welcome Baby!

This study is being conducted by Dr. Ellen Demerath Ph.D. Division of Epidemiology and Community Health at the University of Minnesota, Patricia Fontaine, M.D. Senior Clinical Investigator at Health Partners Institute for Education and Research, and David Fields, Ph.D. at University of Oklahoma-Health Sciences. It is funded by the National Institute for Child Health and Development (NICHD).

Study Purpose

The purpose of this study is to learn more about how breast milk is related to mother and infant weight gain and body composition (the amount of muscle and fat that is in your body). About 360 mothers/infants pairs will take part in this study from Minnesota and Oklahoma, with about 225 participants from Minnesota and 135 from Oklahoma.

Interested in Participating?

We are currently enrolling pregnant women only through our research partners, Health Partners (not through an open enrollment process with the general population).  If you would like to learn more about the study, please come visit us at the Driven to Discover building at the State Fair where for that time only we will have an open enrollment process for women who meet the inclusion criteria!

Study Developments

By investigating how our biology predicts and affects breastmilk production, we hope this research will support the needs of women as individuals. By studying how biology influences breastmilk nutrition, we hope to learn more about why breastmilk is such a good meal for growing babies.

We are busy working with the data we’ve collected so far! Below are some recent findings and statistics from the MILK study:

Preliminary Data: The MILK study's first subjects

Preliminary Data: The MILK study's first subjects

Completed all 3 visits8932
Average age of baby in weeks when mom went back to work99
% of study babies with big brothers/sisters60.2%64.5%
% of study babies that are first babies39.8%35.5%
% of moms still exclusively breastfeeding at three months86.4%96.9%
% of moms still exclusively breastfeeding at six months75.9%65.6%
Average baby body fat % at 1 mo16.2%19.7%
Average baby body fat % at 3 mo23.3%23.5%
Average baby body fat % at 6 mo34.4%34.7%
Breast milk fat content % at 1 mo4.9%5.5%
Breast milk fat content % at 3 mo4.7%5.5%

Abstract: Milk Production & Maternal Pre-Pregnancy BMI

Abstract: Milk Production & Maternal Pre-Pregnancy BMI

Title: Breastmilk output is negatively related to maternal pre-pregnancy BMI and pregnancy glycemia in nondiabetic, exclusively breastfeeding women (abstract)

  • We know that women with higher body mass index tend to have more difficulty starting and continuing breastfeeding. One reason cited for this issue is lower production of breastmilk in this population. This study connected pre-pregnancy weight status and blood sugar levels (glucose) to the way women’s bodies produce milk after giving birth. At 1 month after giving birth, non-diabetic, exclusively breastfeeding women who had a higher weight status before pregnancy produced less breastmilk. At 3 months after giving birth, non-diabetic, exclusively breastfeeding women whose cells processed glucose less effectively during pregnancy produced less breastmilk. 

Abstract: Milk Composition & Maternal Pre-Pregnancy BMI

Abstract: Milk Composition & Maternal Pre-Pregnancy BMI

Title: Altered breastmilk hormone concentrations in non-diabetic, obese, exclusively breastfeeding women (abstract)

  • This study looked at the relationship between pre-pregnancy weight status in non-diabetic women and breastmilk composition. At 1 and 3 months after giving birth, heavier women had higher levels of insulin and lower levels of adiponectin in their breastmilk. Insulin is a hormone that helps our bodies effectively use sugar (glucose), and it’s important to keep these levels from becoming too high. Adiponectin is a protein that protects against inflammation in the body and is associated with the way we metabolize energy from nutrients. The next step in this research is to look at whether these levels are associated with infant growth and development.
Infant Feeding Resources

For more information on breastfeeding and infant nutrition practices, visit our feeding resources page!

Another on the way?

Stork with baby

If you're pregnant again and interested in enrolling your new little one in the Milk Study, we'd love to hear from you!

MILK in the news!

TV By Everaldo Coelho and YellowIcon [LGPL, via Wikimedia Commons] - Background color changed from black to white by uploader.Check out our feature on WCCO! The station filmed a visit with one of our moms who is back for the study with her second baby.

Happy birthday!

Happy BirthdayOur MILK Study babies began turning TWO this November
Happy 2nd birthday to all of our wonderful participants!

Contact us

Further study participation

Many of you have inquired as to how you and your children can participate in other research studies here at the University of Minnesota. The Institute of Child Development (ICD) conducts many studies with children of various ages.

Enroll in the ICD participant pool