Immune testing may reveal if your embryos are being killed off by your own cells
Your immune system is hugely complex. Think of it like a network of armies that defend you against harmful enemies. So what’s the link with women who have an unexplained failure with IVF? The theory is that some women have over-zealous immune systems and they use natural killer cells (NK cells) to attack an embryo or foetus while it’s developing in the womb.
What are natural killer cells?
These cells live in the uterus and their job is to fight off disease and illness. If they detect something foreign, they attack it so it can’t harm you. When an embryo is inserted into the uterus, ‘faulty’ cells think it’s harmful so they kill it off. An immune system that worked correctly would only detect and attack real threats such as bacteria, parasites and viruses.
Who should go for immune testing?
- If you’ve suffered repeated miscarriages and failed IVF with good embryos
- If you have endometriosis (this increases NK cell activity)
- If you have auto-immune disorders like lupus or scleroderma, connective tissue disorders or rheumatoid arthritis
What is the test?
Some doctors favour a blood test, others prefer to take a sample from the womb to count the number of NK cells. If these tests show your NK cell number or activity is ‘high’ you may be offered an immunosuppressive therapy to reduce the cells in the uterus to a normal level.
Does it work?
Immune testing is controversial. Many in the medical community are sceptical that it is a useful test. The UK’s authority on IVF, the HFEA, says that “there is no evidence that immunosuppressive therapies improve your chance of getting pregnant”.
It is hard to prove that testing and subsequent treatments affect the success or failure of IVF. On the other hand, there are genuine stories of women who suffered endless miscarriages and became pregnant after taking medication to reduce the killer cells.
- Be aware that the tests only take a snapshot in time of your immunity, it can change day by day depending on what your body is fighting off – or not
- Labs use different protocols because it’s not a standard test so results for the same test from different labs may vary widely, making interpretation difficult
- Getting your immune system right isn’t everything; the sperm and eggs have to be right too
- It may be worth having the sperm DNA fragmentation test to see if there’s a problem there.
What happens if your doctor says no to the test?
Find a clinic that does consider immunology to be important.
How much does it cost?
- IVIg (Intravenous Immunoglobulin G) consists of human antibodies, made from pooled donor blood that is washed and processed and it’s expensive – £1000-£2000 per transfusion and several may be needed (up to four hours per session)
- Intralipid infusion therapy consists of soy oil, glycerine and egg yolk based liquid (dubbed ‘the mayonnaise miracle’) and is injected into the arm. It takes around one to two hours per session (half the time of IVIg) and you only need around 2-3 sessions. Also it’s harmless (if you’re not allergic to egg/soy) and costs £500 for 2 treatments, and around $100-200 per treatment in the US so it’s much cheaper than IVIg
Intralipids versus IVIg, which is best?
Professor Robert Winston is not a believer. In 2012 he tweeted this comment: “Intralipids are peddled for so-called immune infertility. Yet another remedy being used without real evidence it works.”
Fact is, NK cells and the link to infertility is still new science and there haven’t been any large scale studies to prove it works, but more and more clinics are looking into it. An immune test may be worth doing if you have tried IVF two or three times with good quality embryos – particularly with embryos that have been PGD tested for genetic conditions.
Questions to ask your clinic
- Is this the best test for your problem?
- What is the risk of not having the test done, and what are the alternatives?
- Are there any side effects?