Nonprescription and complementary medication in obstetrics.

Abstract

Pregnant women frequently are either prescribed medication or elect to consume complementary and alternative medicines.1-3 A recent multinational study of approximately 9500 women reported that 81% of women had taken at least one medication whilst pregnant (prescribed or over-the-counter (OTC)), typically analgesics, antacids, anti-allergics and systemic antibiotics.3 Although only a few medications have been demonstrated to be major teratogens, the thalidomide shadow is still ever-present in both healthcare providers' and women's thoughts. There has long been a reluctance to prescribe or consume medication in pregnancy, sometimes in the situation where it would be detrimental to the health of the women and her pregnancy not to do so. One of the major barriers to establishing safety profiles for medications in pregnancy is that most pharmacological trials specifically exclude pregnant women.4 Most medications have some degree of transplacental transfer, and some may have the potential to produce birth defects in the fetus (eg retinoic acid, methotrexate, sodium valproate) or induce reversible or irreversible adverse effects (eg nonsteroidal anti-inflammatory medications, angiotensin-converting enzyme inhibitors). The risk of inducing a birth defect for any medication also is related to maternal systemic exposure, the dose and the route of administration. This Australian categorisation system for prescribing medicines in pregnancy has been developed to assist medical practitioners in medication provision in pregnancy. Not all medicines approved for use in Australia are included in the Prescribing Medicines in Pregnancy Database. Examples of medicines exempted from pregnancy classification include aromatherapy, herbal medicines, homoeopathic medicines and traditional medicines (eg Traditional Chinese). This exclusion is significant as the use of complementary and alternative medicines (CAM) is increasing.6 In a recent Australian study of 1835 women, 52% reported using CAM (excluding vitamins and minerals) during pregnancy.2 Herbal medicine is a common CAM, particularly ginger, cranberry, raspberry, echinacea and chamomile,67 with use most typically as a complementary therapy to pharmaceutical drugs.8 Herbal medicines are usually taken for pregnancy-related symptoms (eg nausea, preparation for labour) rather than chronic conditions.6 CAM modalities are not restricted to herbal therapies but also include vitamins, massage, yoga and relaxation. The most common reasons for choosing to use CAM in pregnancy are the beliefs by pregnant women that CAM offers a safe alternative to pharmaceutical medications, the concept of a holistic approach to care and a need to have control over the pregnancy.8 It has been reported that women typically rely on informal information sources in their decision to use herbal medicines in pregnancy.6 Given that the recent study by Kennedy et al6 noted that urinary tract infection (UTI) was a frequent reason for taking herbal medicines such as cranberry, it is important that women are aware of the risks of not taking antibiotics to treat a proven UTI. Raspberry leaf has been promoted as a uterotonic agent to assist in preparation for labour; however, the evidence for its efficacy is weak.9 In this issue of ANZJOG, Charaf and co-workers10 extend the data on CAM in pregnancy to the preconception period. Although CAM use was not commonly used in the preconception period, there was a clear cohort of women who believed these agents may be of assistance to their conception and early pregnancy care. It is evident from the data emerging that many women do not inform their obstetrician about CAM use – 62% in one study from the United States.11 There is a perception amongst many pregnant women that CAM are ‘natural’ and do not cause harm – in fact, there is little known about the safety of CAM use in the preconception period and pregnancy. Unlike prescription medicines, CAM are not included in the TGA categorisation of medicines in pregnancy and given that some herbal medicines contain ingredients with phar-macologically active ingredients, this may be of concern. The most common source of knowledge about CAM in pregnancy is frequently family and friends.12 Skouteris and co-workers in a study of CAM use in pregnancy in Australian women noted that a quarter of women were planning to use CAM in preparation for labour.13 In this study, there was no association with maternal age, income or education and CAM use: it is clear that as healthcare professionals, we need to specifically ask all women about CAM use, elicit the precise nature of the agents taken and resource the potential effects (if any) of the agents on the woman and her fetus. It is also important to note that medical practitioners are utilising forms of CAM in their therapeutic approach to care, such that for many aspects of CAM (eg acupuncture), there are now overlapping boundaries. This expansion of care may facilitate ongoing research into CAM in pregnancy – for the benefit of women and their fetuses.