The aim of this work was to study the associations between medication use, fear of childbirth, and maternal mental health. Pregnant women (n = 1,984) were recruited through routine antenatal care at a Norwegian hospital from November 2008 through April 2010. Data were collected by three self-completed questionnaires at pregnancy week 17 and 32 and at 8 weeks postpartum. Fear of childbirth was measured by the Wijma Delivery Expectancy Questionnaire (W-DEQ). Symptoms of anxiety were measured by the Hopkins Symptom Checklist (SCL-25) and symptoms of depression by the Edinburgh Postnatal Depression Scale (EPDS). In total, 57.7 % of the women used medications during pregnancy. Analgesics were used by 55.8 % of the women and psychotropic medications by 1.8 %. In all, 7.8 % of the women reported fear of childbirth (W-DEQ >85), the prevalence of anxiety (SCL >18) was 11.8 % and the prevalence of depression (EPDS >13) was 8.1%. Fear of childbirth was significantly associated with use of psychotropic drugs (OR 3.63; 95 % CI 1.39-9.43) but not with the use of analgesics or medications in general. The presence of symptoms of anxiety or depression increased the magnitude of this association. Fear of childbirth is associated with an increased use of psychotropic medication. This finding could not only be explained by an overlap between fear of childbirth and impaired mental health.