HealthDay News — Maternal thyroid hormone trajectories may impact behavioral development in preschool-aged boys, according to a study published online Jan. 6 in the Journal of Clinical Endocrinology & Metabolism.
Peixuan Li, from Anhui Medical University in China, and colleagues examined the sex-specific effect of thyroid hormone trajectories on preschoolers’ behavioral development. Pregnant women were recruited at the first antenatal checkup from May 2013 to September 2014; the analysis included 1,860 mother-child pairs. Maternal thyroid hormone (thyroid stimulating hormone [TSH] and free thyroxine [FT4]) levels were categorized into high, moderate, and low trajectories. Behavioral development was assessed at age 4 years.
The researchers found that a maternal high TSH trajectory was related to withdrawal and externalizing problems in boys (odds ratios, 2.01 and 2.69, respectively), while a moderate TSH trajectory was associated with aggressive behavior (odds ratio, 3.76). There were associations observed for a maternal high FT4 trajectory with anxious/depressed and total problems (odds ratios, 2.22 and 1.74, respectively), while a low FT4 trajectory correlated with aggressive behavior (odds ratio, 4.17). No significant associations were observed for girls.
“It is worth noting that, our findings regarding the effect of maternal thyroid hormone trajectories on preschoolers’ behavioral development are only observed in boys,” the authors write. “The potential mechanism is unclear.”