Prevalence trends and individual patterns of ADHD medication use in pregnancy in Norway and Sweden, 2010–2019

Abstract

Purpose: This study aimed to describe recent trends in ADHD medication use in pregnancy in Norway and Sweden, including prevalence, individual characteristics, and patterns of use. Methods: We studied ADHD medication use (amphetamine, dexamphetamine, methylphenidate, atomoxetine, lisdexamfetamine, guanfacine) by year and age in pregnancies from 2010 to 2019 identified from the medical birth registers (gestational age ≥ 22 weeks) linked to prescribed drug registers (Norway, N = 577,116; Sweden, N = 1,118,988). We compared characteristics of those who used any ADHD medication in pregnancy to no use in pregnancy. Discontinuation was defined as no use after first trimester. Results: ADHD medication use increased from 2010 to 2019 by 3.0 users per 1000 pregnancies in Norway (from 2.5 to 5.5/1000) and by 6.3 per 1000 in Sweden (from 1.6 to 7.9/1000), mainly driven by methylphenidate and since 2015 by lisdexamfetamine. Medication use has increased among pregnant individuals of all age groups, with higher use among the youngest. Pregnant individuals who used ADHD medication were less likely to be married/cohabiting, more likely be nulliparous and to smoke. They had particularly high use of co-medication with antidepressants, anxiolytics/hypnotics, and opioids: 42% in Norway and 65% in Sweden used at least one additional class of psychotropic medication. Most individuals discontinued ADHD medication in pregnancy (85% Norway, 78% Sweden). Conclusion: ADHD medication use during pregnancy increased in Norway and Sweden in the last decade. However, discontinuation rates during pregnancy were high. Those who used ADHD medication had more risk factors for pregnancy complications including low parity, smoking, and other psychotropic drug use.