It may be possible to predict preschool boys’ emotional and behavioral problems well in advance due to a link that researchers have established between abnormal thyroid hormone levels during pregnancy and possible behavioral problems in preschool boys.
The study published in the Endocrine Society’s Journal of Clinical Endocrinology & Metabolism say that Thyroid hormones are crucial for normal development of a baby’s brain and nervous system. During the first trimester—the first three months of pregnancy—a baby depends on its mother’s supply of thyroid hormone, which comes through the placenta. Levels of maternal thyroid hormones, including thyroid stimulating hormone (TSH) and free thyroxine (FT4), change dynamically during pregnancy, and both high and low maternal thyroid hormone levels can affect children’s behavioral development.
The researchers studied 1860 pairs of mothers and their children from the Ma’anshan Birth Cohort in China. The researchers repeatedly measured thyroid hormone levels in the first, second and third trimesters of pregnancy. The researchers followed up with the families when the children were 4 years old and had them fill out a checklist to evaluate their behavioral problems.
The researchers found boys born to mothers with high thyroid hormone levels during pregnancy were more likely to be withdrawn, have behavioral problems and be anxious or depressed. Moderate and low thyroid hormone levels were associated with aggressive behavior in preschool boys.