Reproductive medicine is not limited to the relatively simple practice of fertilising an egg in vitro, and then transferring one or two embryos to the woman’s uterus. Rather, there are now multiple additional interventions that are intended to improve the success rates of IVF. The combination of a poor evidence base, commercialisation and patients’ enthusiasm for anything that might improve their chance of success, results in a ‘perfect storm’ in which dubious and sometimes positively harmful treatments are routinely both under-researched and oversold. In this chapter, I will argue that, although giving patients information about the inadequacy of the evidence-base behind add-on treatments is important and necessary, this should not be regarded as a mechanism through which their inappropriate use can be controlled. Instead, it may be necessary for the Human Fertilisation and Embryology Authority to categorise non-evidence-based and potentially harmful treatments as ‘unsuitable’ practices’, which should not be provided at all, rather than as treatments that simply need to be accompanied by a health warning.

In this chapter, the evidence and use of in vitro fertilisation (IVF) add-ons in the UK is explored. In addition, the stance of professional and regulatory bodies is described. The term ‘add-on’ has been coined to describe the additional ‘extras’ to a routine or intracytoplasmic sperm injection cycle that are commonly offered to those undergoing treatment with the aim of improving livebirth rates. A summary of the highest quality available evidence for the following add-ons is presented: endometrial scratching; time-lapse imaging; assisted hatching; preimplantation genetic testing (PGT-A); endometrial receptivity array; GM-CSF containing culture media; Embryo Glue (hyaluronic acid); artificial egg activation with calcium ionophore; intracytoplasmic morphologically selected sperm injection (IMSI); physiological intracytoplasmic sperm injection (PICSI); sperm DNA test; and reproductive immunology procedures. There remains a paucity of evidence to support the routine use of add-ons based on the available randomised controlled trial and systematic review evidence. This is particularly important given that most patients pay additional fees to utilise add-ons. In order for patients to receive high- quality care in IVF clinics, clinicians must be prepared to discuss the relevant evidence regarding efficacy and safety of the specific add-on being considered.