The use of complementary and alternative medicine (CAM) and therapies has increased in Australia [1, 2] as in many other developed countries [3, 4], and 65–80% of the world's population use traditional medicine as their primary form of health care [5, 6]. There are limited data on the extent of women's use of either herbal or vitamin supplements during pregnancy , despite the fact that knowledge of the potential side effects of many of these products is limited, particularly with respect to their use in pregnancy [8–11]. Although regulation of alternative medicines has improved in Australia herbal medicines are still not subject to the same scrutiny in terms of safety, efficacy and constituents as conventional medicines , although many consumers assume or expect this to be the case . Many consumers do not inform their primary care provider about their use of these alternative medicines [2, 12].
Cross-sectional surveys in one Australian state in 1993, 2000 and 2004 demonstrated high levels of use of CAMs and CAM therapists [1, 2, 12]. While overall use of CAMs was stable, with approximately 50% of respondents using at least one non-medically prescribed alternative medicine in the previous year, there was an increased number of women using herbal medicines . Users of CAM are more likely to be female, better educated, employed [2, 13, 12] and have a higher income [2, 12].
Several papers specifically report on the use of herbal supplements or medicines in pregnancy, and the studies are summarised in Table 1. Herbal use reported in pregnancy ranged from 7% to 96%. When considering only studies from Australia, use of herbal medicine in pregnancy ranged from 10–56%. There is a trend that smaller studies have found higher prevalence of herbal medicine usage. Pinn and Pallett  reported a relatively low prevalence (12%), but only asked women in mid-pregnancy, whereas Nordeng and Havnen  found that use of herbal supplements increased as pregnancy progressed, supporting trends noted in a previous Finnish study .
Characteristics of women more likely to take herbal supplements in pregnancy include being older ; married ; primiparous [8, 17]; having tertiary level education ; previous herbal use ; being white ; and being less educated . One study found older women were less likely to be taking herbal supplements ; another reported that the only predictor of increased use of herbal medicine in their study of nausea in pregnancy was increased severity of nausea and vomiting .
The use of herbal supplements during pregnancy may be pregnancy related, for example for nausea and vomiting [19, 7, 8], reflux , candida , nutritional , or to prepare for labour ; or may be for unrelated health issues such as colds and respiratory illnesses  or skin problems . Reasons reported for ceasing herbal medicine supplements during pregnancy include concerns for the health of the fetus/baby [8, 16, 19], the 'condition' improving , the supplement not helping  and advice from a health care provider .
Herbal supplement use in pregnancy has been reported to be recommended by health care providers [16, 19], natural/alternative medicine practitioners [18, 19] or pharmacists ; suggested by friends or family [8, 10, 16, 18, 19]; based on information from media sources ; or based on women's own information and knowledge [15, 16]. Women may choose to use herbal supplements because they consider them safer during pregnancy than pharmaceutical products . MacLennan et al.  reported that nine percent of their sample considered that alternative medicines were safe to use in pregnancy, and 36% considered they were unsafe, with the remainder unsure (28%) or varying depending on the medication 27%.
Information on herbal use may not be specifically elicited during pregnancy care. One study found that 75% of women reported their supplement use during pregnancy to their primary care provider , and another reported that the use of herbal supplements were documented in only two (1%) of the women's medical records where women had reported taking herbal supplements during study data collection ; it is not stated whether this was because women did not tell pregnancy providers or whether providers did not document the information. In an Australian study only 36% of participants informed their primary medical carer of alternative medicine usage .
Our aim was to explore patterns of herbal medication use including dietary supplements in pregnant women. We expected that in keeping with the increased use of herbal and alternative medicines in the community generally, we would find a relatively high proportion of women attending for pregnancy care were using herbal medicines periconceptionally, during pregnancy, labour or in the puerperium. We also expected that the use of herbal remedies might differ between cultural groups. This paper presents the findings relating to herbal medicine use in pregnancy.
Ethics approval was obtained from the Mercy Health and Aged Care Research Ethics Committee.