Introduction
A teratogen is a substance that can adversely affect the development of an embryo or a foetus on exposure during pregnancy. A wide range of substances have been recognised as teratogens, including some medications [1, 2]. There is a need to ensure that potential teratogens are used as safely as possible by women of child bearing age, because the use of teratogenic medications is likely to be inevitable in many cases due to the unavailability of equally effective alternative treatment options [3, 4].
To support healthcare professionals’ and patients’ understanding regarding the relative of safety of using different medications during pregnancy, evidence-based classification systems have been developed [5]. Within such systems, medications are assigned into different risk categories based on available data on their harm to the foetus, including type, subjects, and results of the available teratogenicity studies [5, 6]. One example of a classification system is the Food and Drug Administration (FDA) pregnancy categories, which classifies any medication within one of five categories (A, B, C, D, or X) based on its degree of safety, with class A being the safest and class X being the most harmful to the foetus [7].
To minimise foetal harm when prescribing potential teratogens, risk management programmes have also been developed for certain medications, with the manufacturer of isotretinoin launching the first pregnancy prevention programme aimed at preventing foetal exposure in 1988 [4, 8]. Subsequently, the use of teratogenic medications has been increasingly controlled through the development of risk minimisation activities and programmes [8]. Elements to ensure safe use of teratogenic medications include certification of prescribers and dispensers, patient counselling regarding contraception use and monitoring patient contraception behaviours through regular pregnancy testing and use of contraception [8, 9].
The development and implementation of teratogenic risk management programmes should also take into consideration patient’s experience of using a medication [10]. The value of recognising patient’s experience of medication-taking as part of ensuring medications are used effectively and deliver intended outcomes is one of the principles of medicines optimisation, a model for informing pharmacy practice based on the aim of improving outcomes of medication use. The four guiding principles of medicines optimisation are: aim to understand the patient experience; evidence-based choice of medicines; ensure medicines use is as safe as possible and make medicines optimisation part of routine practice [11]. Medicines optimisation is a patient-centred approach for achieving optimal use of medications by providing personalised care for each patient [12]. Conceptualised in terms of medicines optimisation, with the patient at the centre of healthcare, patients’ views, opinions, and perceptions of taking a teratogenic medicine, and understanding of teratogenic risk, are therefore important factors when investigating the effectiveness of any risk management programme [13, 14]. Moreover, because a key actor in ensuring evidence-based choice of medications are healthcare providers, these stakeholders’ perceptions of teratogenic risk will play a part in understanding patients’ experience of using the medication [10]. In fact, evidence from the literature suggests that the patient-physician relationship and teratogenic risk communication have a significant impact on patients’ medication utilisation [13]. In this context, over-estimation of teratogenic risk may result in poor adherence to treatment during pregnancy, anxiety or pregnancy termination, while under-estimation of teratogenic risk can result in foetal exposure to the harmful effects of a teratogenic medication [15-17].
A growing body of literature has investigated the implementation of pregnancy prevention measures while prescribing teratogenic medications to women of child bearing age [18-22]. Additionally, research has focused on the perceived risk of teratogenic medications of various populations [15, 23, 24]. Yet to date, what is lacking is a systematic synthesis of data from a medicines optimisation perspective that explores teratogenic medication safety by systematically reviewing publications on the implementation of risk management (pregnancy prevention) measures when prescribing teratogens to women of child bearing age in combination with a review of patients’ experience of using teratogenic medications in terms of reported perceptions of teratogenic risk.