Rapid weight gain in the first and final months of a pregnancy will play a major role in development of excess fat tissue in children and adolescents, especially in girls, according to a new study.
The study by the researchers at the University of Texas at Austin was published in the journal Obesity. The researchers looked at more than 300 pregnant women and followed their children from 5 to 14 years old. They connected patterns of weight change in pregnancy to patterns of their children’s body mass index (BMI), waist circumference and body fat percentage changes during childhood and early adolescence.
WEIGHT CHANGE PATTERN
Assistant professor of nutritional sciences at UT Austin Beth Widen noted that they wanted to understand whether different weight change patterns during pregnancy impacted the child’s growth over time or the child’s potential to develop excess fat tissue.
Widen noted that they did not see much of a difference in the patterns of weight and body size over time in boys. However, for for girls, the researcher pointed out that they came across striking differences ” This tells us there are differences between the sexes in this area of child growth,” Widen said.
Weight change in pregnancy generally followed four distinct patterns in this study. One group of pregnant participants in the study lost weight during the first trimester, gained moderately during the second and gained rapidly during the third. A second group experienced slow weight gain across all three trimesters. A third group saw slow weight gain during the first trimester and moderate weight gain through the end of pregnancy. The last group experienced rapid weight gain during the first trimester, followed by slow weight gain during the second and moderate weight gain during the third. The researchers found that girls born to the fourth group in this study – individuals who gained weight more quickly at the start and end of pregnancy – had the highest body mass index measurements. Conversely, girls born to study participants from the first group – individuals who lost weight in the first trimester, and gained moderately in the second trimester and rapidly in the third – had the lowest BMI, waist circumference and body fat percentages in the study.
No clear-cut pregnancy weight and childhood body composition patterns emerged with boys in the study. Widen speculates this may be due to differences between the sexes in growth and development in addition to differences in how boys and girls respond to prenatal exposures.
Researchers emphasize that finding a pattern in children’s body composition from pregnancy and across childhood is not the same as detecting causation, so further research is needed.
“The study shows us that there may be sex differences in child body composition based on what they are exposed to in uterus,” Widen said. “But, really, we believe there is only a small portion of pregnancy weight gain that can be consciously changed – specifically among fat tissue – since much of the weight change is necessary to support the pregnancy. It is possible that these findings are just the start of research that can help us further understand risk factors for childhood obesity and may help us develop more individualized weight gain guidelines that support pregnant people.”
The research was funded by grants from the Eunice Kennedy Shriver National Institute of Child Health & Human Development, the National Institute of Environmental Health Sciences (NIEHS) and the U.S. Environmental Protection Agency (EPA) Children’s Environmental Health and Disease Prevention Research Centers, Irving General Clinical Research Center, Educational Foundation of America, John and Wendy Neu Family Foundation, New York Community Trust, the Trustees of the Blanchette Hooker Rockefeller Fundi and the National Institutes of Health.