Project Viva - Child Cohort
- National Institutes of Health (NIH)
Project Summary
Project Viva is a groundbreaking longitudinal research study of women and children that began in 1999. Project Viva was started by Principal Investigator Matthew W. Gillman and his colleagues who were intrigued by the notion, then just emerging, that what happens very early in life - even before birth - can have effects on health into adulthood. In 1998, Dr. Gillman implemented a successful pilot study about diet in pregnancy. With financial support from the NIH, Project Viva began enrolling pregnant women in April 1999.
The initial goal of Project Viva was to find ways to improve the health of mothers and their children by looking at the effects of mother's diet as well as other factors during pregnancy and after birth. Over the past two decades, Project Viva has expanded its focus to include a wider range of experiences that influence health extending into midlife for the mothers, and young adulthood for their children. Health exposures of interest now include not only diet but also physical activity, sleep, environmental chemicals, air pollution, stressors, mental health, and others. Project Viva continues to conduct in-person visits with young adult participants (now ages 21+) and sends out annual surveys to track the changes of participants throughout the years.
Study population
A total of 2,128 babies born between 1999 and 2003 were enrolled into Project Viva. Today, more than two decades later, over 1000 young adult offspring continue to be actively engaged in Project Viva research! Project Viva mothers completed in-person examinations during pregnancy, and were seen together with their children at study visits throughout childhood and into the teen years. Project Viva now invites mothers and their children to continue their participation as individuals, as we shift our focus toward separate studies of Young Adult health and Women’s health.
Why is this important
- Medical, governmental, and other organizations have used our results to develop policies and guidelines for medical practitioners and the general public.
- Our findings informed guidelines for healthy weight gain in pregnancy published by the US National Academy of Medicine
- The Environmental Protection Agency used Project Viva research in developing its Strategic Roadmap on PFAS “forever chemical,” setting policies to safeguard public health, protect the environment, and hold polluters accountable.
- Project Viva’s research about prenatal fish intake and mercury exposure in relation to outcomes such as pregnancy health and child cognition influenced the US Food and Drug Administration’s guidance about fish intake in pregnancy and the American Academy of Pediatrics evidence review about fish intake in childhood.
- For the first time in their 40-year history, in 2020 The Dietary Guidelines for Americans included advice on healthy diet for pregnancy and children under age 2 years. Project Viva’s research informed much of this guidance. Viva’s research was also cited in The International Federation of Gynecology and Obstetrics guidelines for healthy diet before and during pregnancy.
Our research on healthy lifestyle informed the work of the White House Task force on Childhood Obesity and Michelle Obama’s Let’s Move! campaign.
Findings so far
Unhealthy environments are responsible for almost one quarter of the burden of disease worldwide, and pregnant women and children are especially sensitive to harms from pollutant exposures. We have measured many environmental chemicals using the blood, urine, hair, and tooth samples that Viva participants provided at study visits. We have also estimated exposures to pollutants in air and water based on home and school addresses.
We were among the first to demonstrate how pre-natal exposure to traffic pollutants can affect blood pressure, respiratory infections, and asthma risk in children. Other studies investigated how pollutants may reduce fetal growth and lead to obesity and impaired neurodevelopment. Lead levels in Project Viva participants were generally low, but even such low exposures in pregnancy were associated with higher risk for preterm birth in boys, and behavioral problems in later childhood.
As is true in the population in general, every Viva mom and child we measured had at least some higher per-and polyfluoroalkyl substances (PFAS) “forever chemicals” in their blood. We have found that higher PFAS levels in early pregnancy were linked to a higher risk of pregnancy complications and impaired thyroid function. Higher PFAS levels in childhood were associated with more behavioral problems and later onset of puberty in girls and, in some cases, greater body fat.
Both the length of pregnancy and fetal growth are important predictors of a baby’s health during infancy and throughout life. In Viva, over 7% of babies were born preterm, which is more than 3 weeks before their due date, 5% had lower birth weight than expected, and 13% had higher birth weight than expected.
We have led research examining factors that can influence birth outcomes. In early work, we did not find that stress induced by the terrorist attacks of September 11, 2001 shortened Viva pregnancies. However, both shorter and longer than average menstrual cycle length in mothers before pregnancy was associated with higher risk for preterm birth. Environmental factors are very important. Higher exposure to PFAS chemicals and higher pregnancy lead levels were associated with higher rates of preterm birth; and higher PFAS chemicals, maternal smoking, and higher air pollution levels all were associated with lower fetal growth.
In other studies, we have examined how these factors at birth predict later health of the child. Viva babies with higher birth weight went on to have higher weight, waist circumference, and body fat into adolescence. Thus, understanding factors that influence birth weight may be important for addressing the epidemic of childhood obesity. Interestingly, preterm birth may also be a marker for future maternal health. For example, we found that Project Viva mothers with preterm deliveries had higher blood pressure and lower HDL (“good” cholesterol) 3 years later.
Our work to understand how birth outcomes relate to health has also led to important scientific advances outside Project Viva itself. Early on, we realized that there were no national standards that we could use to assign percentiles for weight at birth to the Viva kids. Using data from birth certificates across the US from 1999 and 2000, we developed a reference for size at birth. This reference has been used not only in Project Viva, but also in more than 500 other research studies, as well as in hospitals and clinics, to calculate weight percentiles for fetuses and newborns. In 2017, we updated this reference to keep it relevant for the next generation.