Maternal cortisol levels during pregnancy are linked to the development of language in children over time

Higher levels of the stress hormone cortisol during the last three months of pregnancy may improve speech and language skills in the first three years of a child’s life, according to research presented at the 25th European Congress of Endocrinology in Istanbul. The findings help researchers understand the role cortisol plays in fetal and child development.

Language development during early childhood can indicate how well a baby’s nervous system is developing in the womb. Prenatal exposure to cortisol — a steroid hormone that helps the body respond to stress — directs fetal development and also influences its brain development. However, the effects of cortisol on early language development are still unknown.

In this study, researchers from Odense University Hospital analyzed data on the cortisol levels of 1093 Danish women during the last trimester of pregnancy and on the speech and language skills of 1093 Danish children between the ages of 12 and 37 months, from the Odense children’s cohort. They found that boys who were exposed to high levels of cortisol in the womb could say more words at the age of 12-37 months, while the girls were better at understanding more words at the age of 12-21 months.

“To our knowledge, this is the first study to look at the relationship between maternal cortisol levels and children’s language development over time, taking into account the children’s gender and the mother’s level of education,” said Dr. Anja Wenger-Dreyer, who was involved in the study. .

We had access to a large study cohort, high-quality analysis methods and relevant covariates, making our study an important contribution to the physiological understanding of prenatal cortisol exposure in fetal maturation and child development.”

Dr. Anya Finger-Dreyer

The team will then assess whether babies exposed to high cortisol in the womb are more likely to have higher intelligence quotient (IQ) scores. Except for data on maternal cortisol levels and early language development, the Odense Child Cohort also has data on intelligence tests taken by 7-year-olds. “Early language development in children is known to be a predictor of cognitive function later in life, such as attention, memory and learning, so we wanted to investigate whether prenatal cortisol exposure was also associated with IQ scores for children aged 7-years-old.” Dr. Finger Dryer.