Mark Henderson, The Times newspaper's Science Correspondent quotes Professor Bill Ledger of the University of Sheffield in a recent article extolling the virtues of gonadotrophin releasing hormone (GnRH) antagonists in IVF treatment. According to Professor Ledger, 'hundreds of infertile women could be spared the most distressing side effects of IVF' such as hot flushes, night sweats, mood swings and insomnia by a drug regime 'too rarely' used in Britain. He also claimed that for women to use these drugs would also 'significantly lower the risk of ovarian hyperstimulation syndrome, the most dangerous complication of IVF apart from multiple births'.
The article goes on to say that 'Despite these advantages, GnRH antagonists are alleged to be unpopular with British fertility doctors, who consider that they slightly reduce the chances of a successful pregnancy compared with traditional long-protocol IVF drugs.' Professor Ledger is reported as saying that in the UK 'many clinics were too frightened of potentially falling in the success-rate league tables' to use GnRH antagonists.
Let us examine the facts behind this. Are British fertility doctors really so behind the times, not wishing to alter their practices and fearful of a fall in the success rate tables?
An alternative explanation for the perceived reluctance to move to a new 'wonder regime' might be the absence of suitable prospective randomised controlled trial data. What is the efficacy and cost effectiveness of the new regime? Evidence based clinical medicine in IVF is not a mere mantra- but a principle that needs to be upheld in practice. Is treatment using a GnRH antagonist really so beneficial that does not warrant a randomised controlled trial before being introduced wholesale into British fertility practice?
I suspect that clinics are not frightened by a possible (but unlikely) fall in their live birth rates related to the introduction of more patient-friendly protocols. They continue to be concerned about the publication of outcome data that is not published on an intention-to-treat basis. This will soon be rectified by the UK's IVF regulatory body, the Human Fertilisation & Embryology Authority (HFEA). It is likely that hitherto, the differences between clinics in live birth rates following IVF will reflect inter alia how the data is collected and reported, over and above patient selection and treatment protocols.
Patient safety in IVF remains a primary concern. Ovarian hyperstimulation syndrome (OHSS) is an unpleasant condition which affects some IVF patients, and in rare and extreme cases may potentially be fatal. A significant reduction in the incidence of moderate and severe OHSS, by the use of GnRH antagonists would represent a major clinical advance. A large study would be necessary to confirm the speculation that has been made on this, given the relatively low incidence of severe OHSS. Anything that may make IVF safer and more patient-friendly merits our serious consideration. Let those who promote the use of these drugs use their best endeavours to mount the appropriate trials accordingly.
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