New research shows that children in Denmark whose mothers used antidepressants during pregnancy have lower standardised math test scores. However, their scores in Danish language tests are similar to those of other children.
When children solve math problems as part of Denmark’s national testing programme, their results do not only depend on whether they have paid attention.
New research shows that their performance is associated with whether their mothers used antidepressants during pregnancy.
Children whose mothers used antidepressants while pregnant had slightly, but statistically significantly, lower standardised math scores than other children.
A researcher behind the study says that this finding calls for further research into the possible associations between maternal use of antidepressants during pregnancy and children’s cognitive development.
“All types of antidepressants cross the placenta, and there has long been concern about whether using antidepressants during pregnancy may affect fetal brain development. Our study indicates that these may be associated, even if the difference in math performance is small. However, the results do call for further investigations examining the possible biological link,” explains Julie Werenberg Dreier, Senior Researcher, National Centre for Register-based Research, Aarhus University.
The research has been published in the Journal of the American Medical Association.
1.8% of children born to women using antidepressants during pregnancy
The new study includes test scores from 575,369 children born in Denmark who completed a national test in Danish or math between 1 January 2010 and 31 December 2018.
The children were born between 1 January 1997 and 31 December 2009 and had attended a public primary and lower-secondary school.
In total, 10,198 (1.8%) of these children were born to mothers who had filled a prescription for antidepressant medication during pregnancy.
The researchers linked data on the children’s school test performance with information on the parents. Data obtained from the Danish National Prescription Registry showed whether the mothers had picked up prescriptions for antidepressants during pregnancy. Data on the mothers’ medical history and parents’ education and income came from the Danish National Patient Registry and other registries at Statistics Denmark. The researchers received information about the children from the Danish Medical Birth Registry.
In the analysis, the researchers took into account other factors that could affect the child’s test results in school. They also compared how siblings performed in the national tests if the mother had used antidepressants during one pregnancy but not the other.
“Few studies have examined how maternal use of antidepressants during pregnancy potentially affects a child’s long-term cognitive development. We did this by linking data from many nationwide registries with the national test scores, which reflect how the children are performing academically in school – which is closely related to their cognitive ability and intelligence,” says Julie Werenberg Dreier.
Lower test scores in math
If the mother used antidepressants during pregnancy, the child performed slightly worse on the standardised math test.
On a scale from 1 to 100, the math scores of children born to mothers using antidepressants in pregnancy were on average 2 points lower than those of other children, after accounting for parental differences, such as health and socioeconomic status.
“This small but statistically significant difference seems to be associated with whether the mother used antidepressants during pregnancy or not. We found the same difference in the children’s final examination grades and between siblings, when only one was exposed prenatally to antidepressants and the other not. This is a very robust finding.” explains Julie Werenberg Dreier.
The Danish language scores did not differ according to whether the mothers used antidepressants during pregnancy.
“The difference in the math test results is small, and caution is required in identifying causal relationships based on registry data. Nevertheless, we think that examining this association in greater depth would be useful to better understand the context,” says Julie Werenberg Dreier.
Not advisable to discontinue medication
The fact that children risk performing slightly worse in mathematics is not enough for Julie Werenberg Dreier to recommend that mothers stop using antidepressants during pregnancy.
She emphasizes that antidepressants in many instances are used to treat a severe illness that, if left untreated, may have even greater consequences for the child.
The benefits and potential risks of using medication in pregnancy must always be balanced against each other.
“Even though we find this association between maternal use of antidepressants and math performance in school, looking at the broader picture and considering the potential serious consequences of severe maternal depression during pregnancy are also important,” concludes Julie Werenberg Dreier.