Behavioral problems in young children are linked with the levels of thyroid hormones during pregnancy, suggests a new study from China, which examined the sex-specific effect of thyroid hormone trajectories on behavioral development in preschool age children.

The study conducted at the Ma anshan Maternal and Child Health Hospital in China examined 1860 mother-child pairs from the Ma anshan Birth Cohort (MABC), which included pregnant women recruited from May 2013 to September 2014. Researchers excluded women who had either a family or personal history of thyroid disease.

Maternal thyroid hormones – thyroid stimulating hormones (TSH), free thyroxine (FT4) and TPOAb were repeatedly measured during all three trimesters of pregnancy. The mothers and their children were followed up for four years. Behavioral problems in children were recorded with the help of the Achenbach Child Behavior Checklist at 4 years of age.

Results reported in the Journal of Clinical Endocrinology and Metabolism showed high TSH levels in 4.4% of women during pregnancy, moderate TSH levels in 27.8%, while 67.8% had low levels. High FT4 levels were seen in 14.6% of pregnant women, 52.4% had moderate levels, and low FT4 levels were seen in 33% of the women. Boys born to mothers with high TSH levels were more likely to be withdrawn (odds ratio 2.01) and have externalizing problems (OR 2.69), whereas aggressive behavior (OR 3.76) was more common in preschool boys born to mothers with moderate TSH levels. Similarly, high FT4 levels were associated with anxious/depressed behavior (OR 2.22), while the probability of aggressive behavior in preschool-age boys was higher if mothers had low FT4 levels (OR 4.17).

This study has shown an increase in the risk of behavioral problems in preschool boys with abnormal thyroid hormone levels and provides an insight into the genesis of emotional and behavioral problems in children, according to study authors. Hence, its important to closely monitor thyroid hormone status of the mother during pregnancy.

Reference

1. Li P, et al. Sex-specific effect of maternal thyroid hormone trajectories on preschoolers behavioral development: a birth cohort study. J Clin Endocrinol Metab. 2022 Jan 6;dgab887. doi: 10.1210/clinem/dgab887.