Natural killer cell test
Dear Lord Winston

I am a 37 year old Mum of a naturally conceived 8 year old. Due to secondary infertility I am undergoing ICSI treatment. I have had 3 cycles, resulting in 2 early (week 5 then 4) miscarriages. I have been referred for blood tests for recurrent miscarriage. One of these tests is for Natural Killer cells. Please could you let me know your opinion on the Natural Killer cell test, result interpretation and treatment with IVIG. Thank you, E

Dear E,

Sorry – I really do not understand. You say you have secondary infertility with a live birth and you’ve had several miscarriages yet you are undergoing ICSI which argues that your husband is severely infertile. This doesn’t add up in my book.

Can you also explain the acronym ‘IVIG’ – I think I know what this is and, if I am right, it worries me a little.

I look forward to your reply.

Best wishes
Robert Winston

Dear Robert

Thanks for your response and sorry for causing confusion with an incomplete picture of Our fertility history.

We conceived our Son naturally 9 years ago. After trying for a year to conceive a second time we were referred for testing and my Husband was found to have no motile sperm. He has now been diagnosed with partial hypogonadism and azoospermia. Once his Urologist and Endocrinologist had ruled out being able to stimulate or extract sperm for fertility treatment he was put on testosterone injections.

All the basic tests carried out so far regarding my fertility have not highlighted any issues.

We started fertility treatment with a sperm donor last year. I had 3 unsuccessful IUI treatments and then started IVF. The clinic ended up doing ICSI I believe because the thawed sperm had below 40% motility. I was not completely clear why this was necessary as I have been told the donor sperm thaws ‘well’ and has proven fertility at the clinic.

At my consultation following the third ICSI cycle we discussed all the tests that would be considered for recurrent miscarriage. One of the tests we discussed was Natural Killer cells (test details from my medical notes – Natural Killer cytotoxicity with suppression, steroid, IVIG (intravenous immunoglobulin) and intralipid and natural killer essay). It was explained that the tests, interpretation of the results and treatment (IVIG) was controversial with no approved guidelines on how to test and interpret the results and what treatment to use. I am very sceptical about having expensive tests that are not sanctioned by the HFEA and fairly decided that as a healthy individual I would not have IVIG (intravenous immunoglobulin) as part of my fertility treatment.

My question was whether you had been involved in any discussions around Natural Killer cells, their role in fertility and the testing and treatment of them by fertility clinics (having checked other fertility clinics online I see they offer the tests and IVIG treatment).

Please let me know if you need any more information.

Thank you

Dear E,

This is, of course, only my opinion, but I do wonder a little whether you are in the right hands. Firstly, the use of ICSI simply because the clinic has thawed duff donor sperm smacks of incompetence to me. If it is duff, it shouldn’t be used at all. Why did they not just thaw another sample? And did they charge you for the ICSI? It is very likely that your success rate might even be reduced by the ICSI process and in my view no medical procedure should ever be used unless there are really good reasons. This is because every medical procedure, even taking a blood sample from your arm for example, carries some risk – however small – and this must be justified.

I remain completely unconvinced by the NK cells story – I know of no carefully controlled data which clearly show that this will help people like yourself in any way. Added to this, the proposed treatment may not only be useless but could even be dangerous to your general health and I would not allow an infertile of my family willingly go through immunosuppression in this way.

The problem is that there are many unproven treatments out there – most of them very profitable – and infertile couples being desperate are prepared to pay heavily for unvalidated treatments which might just help them conceive. Also, do not be seduced by clinics that claim very high success rates for these treatments when they do have a control group and above all, don’t pay out good money for people to experiment on you. If they want to experiment, and you decide to consent after careful thought, they should be paying for the experiment – not you. In my view the alternative is not ethical and I am surprised that the regulators do not take a more robust line.

With best wishes and my apologies for being so negative,
Robert Winston


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