Predictors of the use of medications before and during pregnancy

Drug use in pregnancy is often reason of concern for mothers and their physicians. However, only few studies investigated predictors of drug use in pregnancy.

To examine maternal characteristics as predictors of medication use in the 6 months before pregnancy and during the first 6 months of pregnancy. To examine whether prescription and over-the-counter (OTC) medication use in the 6 months before pregnancy had an impact on medication use in pregnancy.

Six maternity care units and five community pharmacies.

Data were collected using a specially designed self-reported questionnaire during the period March 2009-March 2010. Logistic regression was used to identify factors associated with medication use.

Adjusted odds ratios (aOR) and 95% confidence intervals (CI) were used as association measures.

A total of 236 women were included in the analysis. After controlling for maternal characteristics, parity of more than one was associated with lower prescription medication use in pregnancy (aOR 0.46; 95% CI 0.22-0.93), higher household income with higher OTC medication use before pregnancy (aOR 3.13; 95% CI 1.22-8.00), and miscarriage with higher C and D Food and Drug Administration (FDA) risk category medication use in pregnancy (aOR 3.65; 95% CI 1.30-10.25). Prescription medication use before pregnancy was associated with higher prescription medication use in pregnancy (aOR 2.49; 95% CI 1.12-5.52), OTC medication use before pregnancy with higher OTC medication use in pregnancy (aOR 35.95; 95% CI 7.95-162.49), and C and D FDA risk category medication use before pregnancy with the same category medication use in pregnancy (aOR 3.54; 95% CI 1.23-10.17).

Different maternal characteristics were shown as predictors of medication use before and during pregnancy. However, medication use before pregnancy was shown as the most important predicting factor for the medication use in pregnancy.