Related Experiment Video
Updated: Jul 14, 2026

Swimming Exercise Protocol and Care Methods for Pregnant Rats
Published on: April 5, 2024
The timing of nutrient restriction during rat pregnancy/lactation alters metabolic syndrome phenotype
Mina Desai1, Dave Gayle, Jooby Babu
1Department of Obstetrics and Gynecology, David-Geffen School of Medicine at University of California, Los Angeles, CA, USA. mdesai@obgyn.humc.edu
Objective:
Modulation of growth of intrauterine growth restricted (IUGR) newborns causes either adult obesity or normalization of body weight and fat. We investigated the impact of rapid versus delayed catch-up growth of IUGR offspring on glucose and lipid profiles.
Study Design:
From 10 days to term gestation and through lactation, control pregnant rats received ad libitum food, whereas study rats were 50% food restricted. Cross-fostering techniques were used to examine effects of food restriction during pregnancy and/or lactation periods. Glucose and lipid profiles were determined in offspring at ages 1 day, 3 weeks, and 9 months.
Results:
Food restriction during pregnancy produced hypoglycemic IUGR pups. Those permitted rapid catch-up growth demonstrated adult obesity with insulin resistance (hyperglycemia/hyperinsulinemia) and hypertriglyceridemia. Conversely, IUGR exhibiting delayed catch-up growth demonstrated normal adult body weight and insulin deficiency (hyperglycemia/hypoinsulinemia) and elevated cholesterol levels as compared with controls. However, these adult offspring had higher glucose though similar insulin levels as control offspring nursed by food restricted dam.
Conclusion:
The timing and the rate of IUGR newborn catch-up growth causes markedly altered adult phenotypes. Although delayed newborn catch-up growth may be beneficial in the prevention of adult obesity, there may be significant adverse effects on pancreatic function.

