Medicinal cannabis in pregnancy : panacea or noxious weed?

The use of medicinal cannabis has been the subject of enabling legislation in Australia since 2016. At present the medical profession has not supported its use for anything but a few indications which include paediatric treatment-resistant epilepsy (especially Dravet's syndrome), pain syndromes associated with multiple sclerosis, Parkinson's disease and chemotherapy-induced nausea. However, in the United States where medicinal cannabis has been legalised in 29 States and Washington DC, nausea is an approved indication in many jurisdictions and this has been followed by widespread use for pregnancy-induced nausea and vomiting. This may prove to be ill advised as serious concerns have been expressed about its safety in pregnancy particularly its proven potential to restrict fetal and postnatal growth as well as to impair childhood cognitive functions such as memory, verbal skills and emotional development. These reported effects on neuropsychiatric behavioural and executive functions may influence future adult productivity and lifetime outcomes. Twenty-one States of the United States approve the use of legal cannabis for nausea and vomiting including its use in pregnancy. This is likely to encourage complacency regarding its fetal risks in pregnancy. In Australia the federal and State legislation restricts use of legal cannabis by placing the pharmaceutical under Sch 8 of the Poisons Act 1971 (Tas) which requires specific application for each individual patient use. It is to be hoped that this will prevent the excesses of use in pregnancy witnessed in the United States.