The Snack Study: The Feasibility of Changing Night-time Food Choices to Improve Glucose Tolerance in Pregnancy

Obesity during pregnancy increases the risk for high glucose and diabetes in the mother, and for obesity and comorbid metabolic disease in the offspring. Results of previous intervention studies designed to improve the metabolic health of obese mothers, and thereby reduce the risk to their offspring, have been modest at best. Furthermore, few studies have proved to be efficacious among low income African American women who have high risk for the transmission of obesity to future generations. The purpose of this study is to examine the feasibility of changing the types of foods and drinks that are consumed at night during late pregnancy in order to improve maternal glucose tolerance and reduce the risk for future obesity in the child. We hypothesize that women who replace their usual night-time foods and drinks with lower glycemic load options will have more stable night-time glucose and lower glucose following an oral glucose load. This intervention will be assessed in a cohort of African American women of low income, who were obese at their first prenatal care visit.

Inclusion criteria

• African American race
• Healthy, singleton pregnancy
• ≤ 28 weeks' gestation at enrollment
• BMI of 30.0 - 45.9 kg/m2 at first prenatal visit
• Reports regular food consumption after 8pm at night that is not attributable to work schedule or other constraints.

Exclusion criteria

• pre-gestation or gestational diabetes
• current smoker
• presence of any medical condition or the use of any medication known to affect fetal growth
• previous delivery of a small-for-gestational age infant (<10th percentile)
• previous delivery of a pre-term infant (<36.0 weeks' gestation)
• inability to communicate in both verbal and written English
• unwilling or unable to consume study-provided foods.