Published it the Australian and New Zealand Journal of Obstetrics and Gynaecology (ANZJOG), the study found 90 per cent of clinics did not have any scientific evidence to support these claims on their websites. Of 10 per cent who did reference publications, these were not found to be 'high quality' evidence. Meaning none of the claims were adequately substantiated either for leading to an increase in success for conception or a live birth. Though a few clinics did outline the evidence for their benefits was limited, for most add-ons, the evidence was 'very low quality, conflicting or so imprecise' that it wasn't clear if they were beneficial, harmful or had no effect.