Path To Birth

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Natural Killer Cells & TTC

Fertility, Infertility, IVF, PregnancyJess Lowe6 Comments
Natural Killer Cells NK Cells IVF Implantation Infertility Pregnancy Loss

When I got the diagnosis of having high natural killer (NK) cells I was surprised. After all we have been pregnant before (albeit both were ectopics). I thought that NK cells were only an issue if you've been trying with no whisper of a pregnancy despite strong embryos. With everything that had happened we thought implantation was the one thing we didn't have a problem with. Our babies implanted - just in the wrong spot!

Once my tubes were removed we assumed it was just a matter of time before we were pregnant again. With nowhere to go our baby would grow safely in the right spot.

Some time later this wasn't happening so my doctor went looking for more reasons and the answers came flooding back. One of them was high NK Cells.

So What Are NK Cells And How Do They Impact Your Fertility?

We all have NK cells in our body - all over it in-fact! Normally they are a wonderful thing - part of your bodies immune defence to attack and destroy any foreign growing objects. They target rapidly dividing and growing cells as this is what illnesses like cancer do.

When it comes to TTC when an embryo implants your hormones and the embryo normally signal to the body that this foreign element is safe - so the body knows to leave it to grow.

An embryo is the very definition of a rapidly dividing cell...but unlike cancer this one is very much desired!

Occasionally what can happen is this message gets lost and the body builds up its defensive NK cells in your uterus.

My understanding is that once NK cells are activated in this area of the body they continue to increase, making subsequent attempts at pregnancy even harder.

High NK Cells can lead to repeated failure to implant or early miscarriages.

Diagnosis Of NK Cells

The NK test involves a biopsy of the lining of the uterus in your luteal phase. This can be taken as part of an investigative laparoscopy so its not as scary as it sounds.

The exact cause of NK cells is often unknown.

In my case there is a chance that is was spurred by a previous pregnancy implanting that had the DQ Alpha gene match I now know I share with my husband (DQ Alpha is a blog of its own but in a nut shell means my body recognises my husbands DNA contribution as me, not separate so encourages my body to attack the embryos as a foreign growth).

But I think ultimately the cause is irrelevant - from what I have seen finding out why won't effect how the problem is overcome!

Treatment Of NK Cells

In basic terms treatment works by lowering your immune system and therefore your natural defences to attacking the embryo as it tries to implant.

Like the rest of IVF exact protocols can differ but a popular treatment is Intralipid - a solution that is injected intravenously - along with blood thinning injections like Clexane and a steroid like Dexamethasone.

It might sound intense, but my experience is that it is no more so than the rest of IVF. The administration of the Intralipid for me has been painless and side effect free!

My Thoughts On NK Cells and TTC

If you are in the category of unexplained infertility, getting good embryos and no joy NK cells might be worth exploring as possible reason.

Not all fertility doctors will investigate for NK cells, and some won't treat for them. It seems to becoming increasingly accepted but there are only currently a handful of doctors that are at the forefront of treatment at the moment in each country.

I can't speak for any other personally than my doctor - Dr Lolatgis at Monash IVF.

If you've had a diagnosis or have a doctor who won't treat them it might be worth a second opinion with someone who will. Google and fertility forums will quickly point you in the direction of Dr's in your area that deals with NK cells.

Dr Geoffery Sher in the US has a great website with a lot of information about NK cells on there.

While the treatment has not worked for me yet (note I have some more complicated issues than just NK cells) I know at least 5 women who were trying for years and now have babies or are pregnant after undertaking NK treatment.

I think it helps when you personally know people who have succeeded with a treatment you are facing - the hope factor goes up!

Do you have NK cells? What has been your experience?