Adolescents whose mothers had thyroid dysfunction during early pregnancy are likely to have poor scholastic performance, according to recent study findings published in Thyroid.
Further, the adolescents own thyroid dysfunction also is associated with difficulties in school performance assessed by self-evaluation, according to the researchers.
Fanni Päkkilä, MD, of Oulu University Hospital in Finland, and colleagues evaluated data from the Northern Finland Birth Cohort 1986 on 5,791 women whose maternal serum samples were obtained during early pregnancy and serum samples from their children at age 16 years (n = 5,829). Researchers sought to determine the effect of maternal thyroid dysfunction on children’s school performance, as well as the child’s own thyroid dysfunction.
Participants’ school performances were evaluated by the main teacher when the child was aged 8 years and again by themselves when they were aged 16 years.
Writing difficulties were the most common problem at age 8 years (16.5%), followed by reading difficulties (11.6%) and difficulties with mathematics (8.2%); 20.9% had difficulties in at least one of those. Scholastic problems at age 8 years did not differ significantly between children of mothers with thyroid dysfunction and those without.
During the self-assessed evaluation at age 16 years, most participants reported being worse than average in Finnish or math (27.7%), followed by being worse than average in math (23.4%), being worse than average in the Finnish language (8.6%) and repeating a class (1.8%). Similar outcomes were found among participants of mothers with hypothyroidism and those with euthyroidism.
Participants of mothers with subclinical hypothyroidism had higher odds of having difficulties in math (OR = 1.4; 95% CI, 0.95-2.08) compared with those of mothers with overt hypothyroidism. Compared with participants of mothers with euthyroidism, participants of mothers with subclinical hypothyroidism were more likely to have repeated a class (OR = 2.14; 95% CI, 1.01-4.53).
Compared with participants of mothers with euthyroidism, participants of mothers with hypothyroidism were more likely to have self-reported difficulties in math (OR = 1.56; 95% CI, 1.03-2.38).
Participants of mothers who were hypothyroxinemic were more likely to have repeated a class compared with participants of mothers with euthyroidism (OR = 3.49; 95% CI, 1.06-11.48); all of these participants were boys.
Prevalence and odds of a participant having severe intellectual difficulty of mild cognitive limitation were not related to maternal thyroid dysfunction.
More difficulties in the Finnish language were found among girls (OR = 2.82; 95% CI, 1.42-5.61) with thyroid dysfunction compared with those with euthyroidism. Self-reported difficulties in Finnish and/or mathematics were more often self-reported among boys with hypothyroxinemic test results compared with those with euthyroidism (OR = 2.13; 95% CI, 1.26-3.62).
“In conclusion, abnormal maternal thyroid function status during early pregnancy increased adolescents’ odds of repeating a class at school and had also some effect on the adolescents’ performance in Finnish language and mathematics at age 16,” the researchers wrote. “It did not, however, increase a child’s odds of having an intellectual problem. Additionally, adolescents’ own abnormal thyroid function status had some effect on their self-evaluated school performance.” – by Amber Cox
The researchers report no relevant financial disclosures.