Regulation is a big factor. The clinic has to pay a fee for every cycle to the regulator, and all the regulations impose many additional staff, procedures and equipment into clinics beyond just what is needed to do the clinical practice. The cost base in the UK, not just for IVF but for medical care is high - but of course, nowhere near as high as the USA; and compared to, say some other European countries the UK has a higher wages structure and cost of living