Adherence to medication for chronic disorders during pregnancy: results from a multinational study

Background For a variety of chronic disorders, low medication adherence during pregnancy may jeopardize maternal as well as foetal health. Little is known about how closely pregnant women follow their chronic pharmacotherapy regimens. Objective To explore the level of adherence to medication for a variety of chronic disorders, namely cardiovascular, rheumatic and bowel disorders, diabetes and epilepsy, during pregnancy and to identify determinants of low adherence during pregnancy. Setting This multinational, cross-sectional, internet-based study was undertaken in 18 countries in Europe, North America and Australia. Data originating from some South American countries were also collected. Methods The study period lasted from 1-October-2011 to 29-February-2012. By using an anonymous on-line questionnaire we collected information about maternal demographics, chronic disorders and related medication use during pregnancy, and women’s pregnancy-specific beliefs about medication. Main outcome measure Adherence to medication during pregnancy via the 8-item Morisky Medication Adherence Scale (MMAS-8). Results A total of 210 pregnant women reported chronic medication use during pregnancy and filled in the MMAS-8. Overall, 36.2 % had low medication adherence. On the basis of the MMAS-8, the rates of low adherence were 55.6 % for medication for rheumatic disorders, 40.0 % for epilepsy, 36.1 % for bowel disorders, 32.9 % for cardiovascular disorders, and 17.1 % for diabetes. A lack of folic acid use, having previous children, and individual pregnancy-specific beliefs about medication were significant determinants of low medication adherence during pregnancy. Conclusion Many pregnant women had low adherence to their chronic pharmacotherapy regimens during pregnancy. Women’s beliefs about medication were a central factor determining low adherence.