BACKGROUND: The use of complementary and alternative medicines (CAM) is growing in Australia, with women higher users than men. Yet, only a few Australian studies have explored the use of CAM during pregnancy. AIMS: To explore the use of CAM, the types of CAM practitioners consulted, physical symptoms/complaints for which CAM are used by a sample of pregnant Australian women, and women's perceptions of the efficacy of CAM in treating those complaints. METHODS: Three hundred and twenty-one pregnant women, who volunteered for a study exploring women's well-being during pregnancy, completed a self-report questionnaire in their late second/early third trimester. RESULTS: Seventy-three per cent of women had used at least one kind of complementary therapy in the prior eight weeks of pregnancy. Over one-third of the women had visited at least one alternative medicine practitioner during pregnancy. Approximately one-third of the women reported taking CAM to alleviate a specific physical symptom, with 95.7% of these women reporting they either got completely better or a little bit better with use of CAM; one quarter reported planning to use an alternative therapy to assist with labour preparation. Age, number of physical symptoms experienced, income level and level of education were not associated with greater use of CAM (P < 0.05); however, women reporting more physical symptoms were more likely to consult a CAM practitioner. CONCLUSION: Findings highlight the substantial use of CAM during pregnancy and the need to have all health professionals adequately informed about such therapies during this life stage.