Does Exposure to Corticosteroids Before Birth Increase the Risk of ADHD?

What you need to know

• Corticosteroids are often given to pregnant women at risk of preterm birth to help the baby’s lungs develop. However, there are concerns about potential effects on the child’s brain development.
• This study found no evidence that exposure to corticosteroids before birth increases a child’s risk of being prescribed ADHD medications later in childhood.
• The findings provide reassurance about the safety of using corticosteroids for preterm births, especially for late preterm births (34-36 weeks) where the benefits are less certain.

Background on corticosteroids for preterm birth

Corticosteroids are medications that can be given to pregnant women who are at risk of giving birth prematurely. These medications help speed up the development of the baby’s lungs, which can reduce breathing problems and other complications after birth.

Doctors typically recommend corticosteroids for pregnancies at risk of delivery before 34 weeks. For births between 34-36 weeks (called “late preterm”), the use of corticosteroids is more controversial. This is because the risks of complications for the baby are lower at these later gestational ages, so the potential benefits need to be carefully weighed against any possible negative effects.

One concern about corticosteroids is whether they could affect the baby’s brain development. Some studies in animals have suggested corticosteroids may increase hyperactivity. There have also been mixed findings from human studies looking at outcomes like ADHD (attention-deficit/hyperactivity disorder). However, many of these studies had limitations that made it difficult to draw firm conclusions.

How this study was done

This study used health records for over 16,000 children born preterm (between 31-36 weeks gestation) in British Columbia, Canada from 2000-2013. The researchers looked at whether these children were prescribed ADHD medications between birth and 2018.

Rather than directly comparing children who did or did not receive corticosteroids, the researchers used a special study design called “regression discontinuity.” This design takes advantage of the fact that corticosteroids are routinely recommended up until 34 weeks gestation, but not after.

By comparing children born just before versus just after the 34 week cut-off, the researchers could look at the effects of being more versus less likely to receive corticosteroids, while minimizing other differences between the groups that could skew the results.

Key findings on corticosteroids and ADHD risk

The main findings from this study were:

• About 5.5% of children in the study were prescribed ADHD medication at some point during follow-up (median follow-up of 9 years).

• There was no significant difference in ADHD medication prescriptions between children born just before versus just after 34 weeks gestation.

• The estimated difference was small - about 1.3 extra cases of ADHD medication use per 100 children by age 13 for those more likely to have received corticosteroids. However, this difference was not statistically significant, meaning it could have occurred by chance.

• The results were similar when looking at children who had 2 or more ADHD medication prescriptions, not just a single prescription.

What this means for pregnant women and families

These findings provide reassurance that exposure to corticosteroids before birth likely does not substantially increase a child’s risk of developing ADHD. This is particularly relevant for pregnancies at risk of late preterm birth (34-36 weeks), where the benefits of corticosteroids are less certain and safety concerns become more important to consider.

However, there are some limitations to keep in mind:

• The study only looked at ADHD medication prescriptions, not actual ADHD diagnoses. Not all children with ADHD take medication.

• The results are most applicable to births around 34 weeks gestation. The effects could potentially be different for births at very different gestational ages.

• While no significant increase in risk was found, the study can’t definitively rule out a small increase in ADHD risk from corticosteroid exposure.

Conclusions

Overall, this study provides important evidence supporting the safety of antenatal corticosteroids when it comes to long-term child neurodevelopment, specifically related to ADHD. The findings can help inform discussions between doctors and pregnant women about the pros and cons of using corticosteroids, especially for late preterm births.

However, decisions about using corticosteroids should still be made on an individual basis, weighing the potential benefits and risks for each specific situation. More research is still needed to fully understand the long-term effects of corticosteroid exposure before birth on child development.