Abstract
Background: Pain is common during pregnancy yet there are few contemporary studies of opioid utilisation in pregnancy. We aimed to describe prescription analgesic opioid use during pregnancy across four regions: Oceania [New South Wales (Australia), New Zealand], North America [Ontario (Canada), United States (US)], Northern Europe [Denmark, Finland, Iceland, Norway, Sweden, United Kingdom (UK)], and East Asia (Hong Kong, South Korea, Taiwan).
Methods: We applied a common protocol to population-based data to measure analgesic opioid dispensing or prescriptions during pregnancy prior to birth in 2000-2020. Populations captured included those with public and private insurance in the US, a sample of primary care practices in the UK and whole-of-population cohorts in the remainder. We examined prevalence of use, defined as at least one dispensing or prescribing and estimated trends over time. We described use by sociodemographic- and pregnancy characteristics.
Results: Among a total of 20,306,228 pregnancies, 1,115,853 (55 per 1000) had at least one analgesic opioid dispensing or prescription, ranging from 4 per 1000 in the UK to 191 per 1000 in the US publicly insured population. We observed the greatest relative decrease in prevalence in Hong Kong (prevalence ratio 0.2; 95% CI 0.1-0.2 between 2005 and 2020) and greatest increase in Iceland (prevalence ratio 4.4; 95% CI 3.7-5.2 between 2004 and 2017). Codeine and tramadol were among the three most prevalent opioids in most populations. In a sensitivity analysis defining opioid use as two or more opioid dispensing or prescribing events, the prevalence of opioid use across populations was 17 per 1000.
Conclusions: In this large multinational study, we observed wide global variation in prevalence of analgesic opioid use in pregnancy, yet patterns of use by sociodemographic- and pregnancy characteristics were relatively consistent. Analgesic opioid use remained stable or downward trending over time in most, but not all, countries.