Beth Widen knows that good nutrition in pregnant women and their infants is essential to their health and development. But it is also one of the most difficult populations to study.
Every person’s body is different and each pregnancy, even for the same person, can be very different. When it comes to studying pregnancy, there are unique ethical concerns that make the type of randomized controlled experiments seen in other areas of human subjects research much more difficult. For example, dietary interventions can have complex and unexpected consequences on fetal development. Researchers must therefore be creative in their experimental designs. Add to that the avalanche of nutrition advice, misconceptions and guidelines that pregnant women are bombarded with (“You’re eating for two,” “No sushi,” “Drink lots of orange juice”), and the intense emotions people may feel about it. nutrition – not to mention the difficulties of finding a diverse research cohort willing to take the time to work with scientists between prenatal appointments – and it’s no wonder that many experts in the field of nutrition avoid the challenge of studying nutrition during pregnancy.
“Surprisingly, nutrition during pregnancy and early childhood is still an emerging field,” Widen said. “We are constantly exploring new measurement and data collection techniques. We are finally beginning to understand some of the complex mechanisms underlying pregnancy that contribute to maternal and child health outcomes. We know that diet, exercise, and metabolic health are associated with pregnancy outcomes, but we do not know exactly how they are all interrelated and specifically which behaviors and factors positively or negatively influence pregnancy outcomes and long-term health.
Pregnancy is an extremely complicated process, as well as a very vulnerable time in the life of the fetus and the pregnant person. It is a condition that changes the body forever for a biological parent. For infants, what happens in utero can have consequences for years, or even for the rest of their lives.
Playbook Update
Many pregnancy recommendations are based on studies dating back decades. Food supplies have changed. People’s behavior has changed. Rates of diabetes, obesity and severe pre-eclampsia have increased. Maternal mortality rates are rising, with disparities disproportionately affecting underserved populations. The stakes are high in the race for ideas that will lead to the best recommendations for pregnant women today and tomorrow.
Widen aims to use his unique blend of skills to provide insight into these important questions. As a registered dietitian, women’s health expert, pediatric researcher and public health scientist, she aims to use and develop the most advanced methods to measure and analyze the bodies of pregnant women and newborns, and document their results subsequent ones. Widen has a seemingly boundless curiosity and enthusiasm for his field of study. She speaks on multiple topics, exuberantly and eager to discuss science and share the discoveries she has discovered. His passion for his work is evident and his enthusiasm contagious.
Molly Bray, chair of nutritional sciences at the University of Texas at Austin, notes that “Dr. Widen strives to dispel the many myths that abound about nutrition during pregnancy and to help parents nourish their infants and their toddlers. Her research lays the foundation for science-based decision-making about how to eat during this critical period of life for the health of mother and infant.
For decades, doctors have recommended a range for weight gain during pregnancy, with the Centers for Disease Control suggesting a range between 11 and 40 pounds, depending on a person’s starting point.
Gaining less than the recommended weight during pregnancy can be dangerous for the person giving birth and for the infant, who may be born too early or too small. Some babies born too small may have difficulty initiating breastfeeding, be at increased risk of illness, and have developmental delays. Gaining too much weight during pregnancy can lead to gestational diabetes, complications during delivery, and an overweight baby. Excessive weight gain during pregnancy can also lead to cesarean delivery and increases the risk of obesity and health problems for the child and parents.
In a recent study published in Pediatric obesity, Widen and her research team found that the amount of weight gained during pregnancy did not have as much of an effect on infants as the mother’s weight before the pregnancy began. Body mass index (BMI), a measure of weight adjusted for height, at the start of a pregnancy was a stronger predictor of newborn adiposity (the amount of fatty tissue in the body) as the amount or trajectory of weight gained during pregnancy. An article published this month in American Journal of Clinical Nutrition examines trajectories of weight gain during pregnancy, which are characterized by when and how quickly weight is gained, and how this affects outcomes for mom and baby.
Long-lasting effects
“Having excess adipose tissue at birth potentially sets you up for a worse trajectory throughout life, including an increased risk of childhood obesity,” Widen said. “With our pregnancy and infancy cohort, the Mother Infant NuTrition Study (MINT), we try to answer some big questions. Is the change in weight during pregnancy important, or is it the composition of the weight: fat versus muscle? Or when during pregnancy we gain weight? What are the downstream effects for mother and baby? And is there anything that can be done to control them?
Another recent study from Widen and her team found that postpartum people who breastfed their babies for at least six months had lower BMI and body weight 4 to 10 years later than those who did not breastfeed, and the association did not vary not according to socio-economic status.
Some of Widen’s most recent work aims to unravel the impact of early life predictors, such as prenatal exposures or infant feeding, on growth. A study published in Nutrition Diary found that infants exposed to HIV in utero but who were not infected were three times more likely to have linear growth failure in the first two years of life than those who had never been exposed.
In order to generate recommendations that apply to a broad population, but remain useful at the individual level, Widen chose to focus on historically understudied high-risk populations and groups. Too many previous studies have focused heavily on healthy white women during pregnancy, she said. Although it takes more time and effort to recruit a diverse sample, it is worth it.
Her studies have included members of Dominican neighborhoods in New York, patients in rural and urban clinics in Kenya, and clinical practices in Austin serving Hispanic families. Widen has conducted field research in Uganda, Kenya and Malawi. Since receiving her Ph.D. in 2012 from the University of North Carolina at Chapel Hill, she has published more than 38 peer-reviewed articles.
A previous study by Widen and his team in 2019 found that a mother’s obesity during pregnancy was associated with poorer motor skills in preschool children and lower IQ in middle childhood in boys . They found that the differences were comparable to the impact of lead exposure during early childhood.
Even as she tries to understand the mysteries of growing new humans, Widen is also thinking about how to use more advanced methods of measurement, analysis, projection and modeling to collect data and learn from it.
“For example, we don’t have good ways to measure body fat levels of babies and children in a typical clinical setting,” Widen said. “What is usually done is that children’s weight and height are measured and then plotted on a weight-length growth curve or a body mass index-age growth curve; However, these do not accurately reflect the body composition of growing children, particularly how much of their weight is fat versus lean tissue.
Widen and colleagues measure adipose tissue using pregnancy-safe imaging techniques in prenatal and postpartum MINT participants.
MAGIC to come
Widen’s observational studies led her to develop interventions to support maternal and child nutrition. Perhaps the project she is most passionate about is the Mothers And CareGivers Investing in Children project (MAGIC) test the program. An interdisciplinary team of researchers in nutritional sciences, human development, family sciences and pediatrics examines adapted feeding and relationships between infants and caregivers to determine the influence of infant eating behaviors on food intake trajectories. weight, health outcomes and risk of obesity. The study uses real-time virtual and in-person sessions to help parents and other caregivers feed their babies during the first year of life.
“The MAGIC trial is one of the first studies of its kind in the United States, combining real-time observations of eating with our intervention program that supports healthy eating and optimal feeding practices during early childhood “Widen said.
Deborah Jacobvitz, professor of human development and family sciences at the University of Texas at Austin, notes that “Dr. Widen’s innovative work is at the forefront of obesity prevention research.” The MAGIC intervention we developed provides parents with the tools necessary to promote their children’s ability to regulate their own food consumption and develop healthy, sustainable eating habits.
