Do Pregnant Women Report Use of Dispensed Medications?

Abstract

Surveillance of drug safety in pregnancy often draws on administrative prescription registries. Noncompliance in the use of prescribed medication may be frequent among pregnant women owing to their fear of fetotoxic side effects. To estimate compliance in the use of prescription drugs dispensed during pregnancy, we compared prescription data from the North Jutland Prescription Database with information on drug use provided by pregnant women to the Danish National Birth Cohort (DNBC), which is a health interview survey. We used the North Jutland Prescription Database to identify all prescription drugs dispensed during pregnancy for the 2,041 women who were enrolled in the DNBC in the County of North Jutland, Denmark. Compliance was defined as the probability of reporting drug use in DNBC after purchasing a dispensed prescription drug. The overall compliance to drugs purchased within 120 days before the interview was 43% (95% confidence interval = 40-46). Drugs used for treating chronic diseases, for example, beta-blockers, insulin, thyroid hormones, and diuretic and antiepileptic drugs, were always reported to be used, but compliance was low for drugs used for local or short-term treatment such as antihistamines, antibiotics, antacids, nonsteroid anti-inflammatory drugs, and gynecologic drugs. Thus, for the latter drug groups the prescription database may provide an incomplete identification of exposure. Neither data source is unbiased regarding actual drug intake. Nevertheless, our results indicate that for some drug groups risk assessment studies based on prescription data may produce false negative results as a result of noncompliance.

Maternal medicine: Drug prescription patterns before, during and after pregnancy for chronic, occasional and pregnancy‐related drugs in the Netherlands

“…Compliance was high for drugs used in chronic diseases but low for drugs used for local or short-time treatment. 24 Furthermore, the prescription database does not include drugs administered in hospitals and OTC drugs. For some drugs, underestimation of exposure may be considerable.…”

Corticosteroid Use and Risk for Orofacial Clefts

“…Although we recommend interpreting these results with caution, an association by timing of exposure cannot be dismissed completely. For comparison, a large US study reported that 0.8% of women received first trimester prescriptions for systemic corticosteroids (Andrade et al, 2004), with actual medication use probably less than 100% (Olesen et al, 2001). Furthermore, the prevalence is similar to what has been found in the National Health and Nutrition Examination Study (NHANES) during the years 1999 to 2008, where 0.5% of women aged 20 to 29 years and 0.6% of women aged 30 to 39 years reported use of oral corticosteroids (Overman et al, 2013).…”

Methodological challenges in using routinely collected health data to investigate long-term effects of medication use during pregnancy

“…Noncompliance with medication use may result in misclassification bias, where some of the women classified as 'exposed' were in fact not exposed during pregnancy. For example, Olesen and colleagues compared reporting of medication use during pregnancy among women enrolled in the Danish National Birth Cohort to the North Jutland prescription database, for those women living in the North Jutland area [Olesen et al 2001]. Medications used for chronic medical conditions (i.e.…”