Sunday, October 2, 2016

Natural killer cells - friend or foe?

The first time I heard the term "natural killer cells" in relation to miscarriages and failed IVF cycles, I thought it sounded awful. As if certain women have these toxic cells in their bodies destroying any potential babies! However, I have since learned that everyone has natural killer cells and they are generally a good thing. They help your body fight off infections and diseases (including cancer) and indicate a strong immune system. The theory, which is quite new in the infertility industry, is that some women (I read somewhere it's around 10-15%) have elevated levels which could then interfere with pregnancies. Initially when an embryo arrives into the womb, it will appear as a something foreign since it will have different DNA, and her body will need to decide that this is something good and should be protected and not fought off. It is a complex process so I guess it's easy to imagine that something might go wrong along the way.

While researching NK cells (which has left me more confused than ever to be honest!) I came across a blog saying that if you have elevated levels then you should figure out why, and not just take medicine to reduce them. That makes sense but I don't think it's so easy. I went to a gastrologist recently to discuss some occasionaly digestive issues I've been having and am now getting tested for celiac, just to rule out any other food intolerances. I hope I don't have any more as living with lactose intolerance is already difficult enough! I'm not sure what else I could be tested for. The gastrologist I went to was actually really uncaring and abrupt. He agreed to do some testing but when I tried to show him the blood tests results, he basically just told me to discuss them with my gyno. I had mentioned my miscarriage following IVF to him to explain why we had done the further blood testing and he looked like he couldn't care less. He certainly didn't show any sympathy. Clearly he doesn't believe that stomach issues may have any connection with infertility. I felt quite upset actually after the encounter. On my way home I was sad thinking about those three IVF potential babies that were transferred into me during the first and second round and what could have been...

These days a lot of people have food allergies and intolerances. It's probably due to the western diet, too many processed foods, plus we eat too much dairy in general. A cow's milk is designed for calves not humans. I still eat dairy with lactase enzyme tablets. Completely cutting it out is just too difficult since I love yoghurts and cheese but I have been trying to reduce the amount. I tried osteopathy two years ago when I was attempting natural fertility options (such as acupuncture) and the lady told me that she has had several women who couldn't get pregnant who she advised to quit dairy for three months and they then fell pregnant shortly after! She had the theory that a lot of people probably have undiagnosed food intolerances that they don't know about but could be causing stomach inflammation. It could be the case that your body then says, oh something is wrong, and the natural killer cells get elevated. One of the women on an IVF forum I frequent was able to substantially reduce her elevated NK cells naturally when she followed the so-called AIP diet (Autoimmune Protocol) which is an even stricter version of the paleo diet. It is great to hear there may be some other ways to treat the NK cells, and I also read something about omega3 helping (I'm taking supplements now), but I don't think I would be able to follow such a restrictive diet for that long!

During my research I came across a website saying how great natural killer cells are, that they fight off cancer and some tips on how to elevate them which seemed ironic since I am trying to do the opposite! In general I rarely get the flu and don't come down with many colds so maybe I do have a strong immune system. The treatment for elevated NK cells can leave you more prone to infections so it's important to be aware of that. I came across IVIG & Intralipid Therapy in IVF: Interpreting Natural Killer Cell Activity for Diagnosis and Treatment which mentions the importance of testing for NK cells in relation to fertility and wishes more reproductive doctors would take it seriously.

However then I also found Fertility Fraud: Natural Killer (NK) Cell Testing which says there are too many false positives and no need for the unnecessary treatments. Another negative article: Natural killer (NK) cells – fertility fraud? which suggests the idea of the human uterus attacking an embroyo it is designed to nurture is "preposterous". And from another post on the same site:
Anxious IVF patients are soft targets for hard marketers. In consulting rooms and online, they’re told their bodies may be sabotaging their pregnancies because their embryos are perceived as infections. This ‘NK’ scare may be completely unfounded. Natural killer cells: you have to hand it to the person who coined that phrase. It’s a mortifying description for vulnerable IVF patients willing to try anything to improve their chances. The truth is, intralipids might help. Might. Not will

The next article I read, Reproductive Immunology – What is the truth about Natural Killer cells? sums it up such;
Studies looking into these cells have produced conflicting results, but the majority of leading scientists in this area dispute that Natural Killer cells are a problem in fertility treatment and pregnancy. Given the potential side effects accompanying Natural Killer cell treatments, there does not seem to be enough justification for undergoing this testing and treatment.

Reading all those of course makes me wonder if the tests and treatments could just be a complete waste of money, unjustified and potentially put my health or that of my future unborn baby at risk. Going through IVF, I am already prepared to take certain risks with my own health but I definitely would not want to negatively affect any children! Then again I also read lots of sites which were on the other side of the controversy, for instance: Miscarriages can be Prevented, and this study which concludes:
The results of present study demonstrated that the level of NK cells as a risk factor is associated with pregnancy loss in women with IVF failure.

There was also this interesting article: Natural Killer Cells & Fertility:Cutting Through the Controversy which summarizes;
Studies are beginning to surface that demonstrate IntraLipid therapy does in fact improve the odds of pregnancy for those with recurrent implantation failure. In fact, well-reputed journals (Human Reproduction (2016) 31 (1): 217–218; “The absence of evidence is not the evidence of absence” and (2015) 30 (7): 1526-1531 “Enough! Stop the arguments and get on with the science of natural killer cell testing”) are publishing articles outlining both the pro’s and con’s of testing natural killer cells. Unfortunately, many people opposed to the testing only cite the publication that argues against it. That being said, not everyone requires testing for natural killer cell activation – it should be reserved for certain patients that have already demonstrated an implantation issue. And treatment of these individuals, should their test be positive, has been successful in thousands of anecdotal cases.

I asked around a bit. Two doctor friends think that having high natural killer cells does not cause fertility issues and the numbers can just be raised due to other factors such as stress and to be wary of any "treatment". I heard from someone else who has a doctor friend in Hannover that specializes in fertility that she has had eight patients helped by the NK treatment, even a few of them who got pregnant naturally after failed IVF! I've also read loads of stories on forums from women who had several miscarriages and then got the treatment which worked for them. It doesn't work for everyone though, I know that. Hearing the positive stories makes me hopeful and I think it could be worth trying in our case. That said, I do feel somewhat uncomfortable about it and will definitely be asking my doctor a lot about the risks and side effects.

Would you pursue the natural killer cell treatment if you were me?


  1. Oh, this is a tough one. None of my clinics really backed IVIG or intralipids, and I honestly don't remember if they even tested me for Natural Killer Cells. HOWEVER, another clinic in our area regularly did IVIG and intralipids, and they did have success, although I don't know rates since they are "kitchen sink" people and it's hard to tell what the actual thing is that gets people pregnant. I so agree with this: "Anxious IVF patients are soft targets for hard marketers." There was very little I wouldn't do if told it would help get me pregnant when I was in the midst of IVF. Ironically, though, I couldn't successfully go dairy free. I have celiac, and so I feel like dairy is my right, and there are other studies that show that full-fat dairy is helpful for getting pregnant so who was I to believe? (The one that let me eat cheese. That one.). I am SO MAD at your gastroenterologist. There is a clear link between celiac and miscarriages/infertility. They need better training, to just foist you off to your ob/gyn is beyond insensitive and poor doctor-ing. I can't offer advice per se, but for me if it seemed like it would be helpful and my doctor was willing to try it, I did it because you don't know. Weigh the risks. See what your doctor says. And then make your decision accordingly. Best of luck to you...

    1. At this stage I am starting to feel somewhat desperate, like I would try anything if I thought it would work! So I am definitely and easy target for this. I hate the idea of being a guinea pig for the fertility industry though and of I worry about risks to any babies and side effects for me. Someone told me that they just need more clinical studies in this area and that's why some people are so against it but more doctors are starting to see that there is something to it and it can help in certain cases.. I hear ya on the dairy, I also find it impossible to quit it completely. There is something addictive in cheese though think I remember reading that somewhere!

  2. I understand your need to find and answer but honestly I would not believe what you read on the internet unless you are reading the original research reports produced by doctors. So many people will sell you on diets and snake oil cures but you might never actually know why you can't conceive.
    I have secondary infertility and I just had my fifth miscarriage, this time I was 11 weeks, and it has many health complications because I was so far along. Of course I will not stop trying to have a baby, but I have accepted I will never really know why this keeps happening to me. Infertility is both mysterious and very painful. I wish you luck and think you are brave for writing about it. I cannot let myself think about 'what if' anymore because it would drive me crazy and I would not be able to get out of bed in the morning. All of my friends are pregnant with their second and third children. I can only hope that someday I will get lucky and carry to term. Hope can be insidious as well as sustaining but I refuse to give up.

    1. Thanks for your comment, I appreciate the honesty. I will definitely be asking my doctor if she can point me to the research and testing and make sure I am well informed as much as possible before deciding. I am really sorry to hear what you are going through. Miscarriages are just heartbreaking, and I'm sure at 11 weeks it must have seemed like you were almost in the clear. I hope that your health complications will improve and I really hope that you will be able to carry to term soon.

  3. Your gastroenterologist sounds horrible! Maybe you should find someone else? I hope you don't have coeliacs disease... avoiding gluten is HARD! (Jan's cousins all have it).

    This all sounds really confusing. Just like everything to do with fertility there is so much contradicting information out there... it's impossible to know what to believe.

    I have also read omega 3s are supposed to be helpful. I started taking fish oil this month. Zinc is also supposed to be good, for both male and female fertility.

    1. Yea it might be worth finding a nicer gastroenterologist if I can, and going with my husband next time as I doubt the doctor would have been so mean if I hadn't been on my own! I hope I don't have to avoid gluten. Loads of people these days seem to have issues with it! The natural killer cells issue is definitely very confusing, and there seem to be so many potential issues involving infertility it's so hard to figure out what to try and what might work in our case!

  4. Sorry to your gastroenterologists was so awful. You posted a lot of good research here!

    If it were me and it wasn't too expensive to try it once, I'd consider trying it once to see how my body responded. But if even one try carries big risks I'd be hesitant.

    I tried chemical IVF once and it had terrible results. I tried Clomid and I responded poorly. But I gave them a go.

    Now I stick to natural IVF and it works for me. It got me pregnant once.

    But I wouldn't have reached this point if I didn't try other things first.

    However, if it's dangerous and too expensive to try once, then I probably wouldn't even do that.

    Best of luck! *fingers crossed*

    1. Yea I'm kind of torn between whether I should try another round without getting the natural killer cell treatment first or whether to go for it now. Once I find out more about the risks and costs etc, it should help me decide. That's great that natural IVF seems to work well for you. I would consider trying that if I don't respond well to the meds again next time. I'm crossing my fingers for you too :)

  5. Yikes! First off, our gastro sounds like a real dud. Hopefully you won't have to go back to that miserable guy for awhile (or ever)!

    When I asked my RE to run an RPL panel, he tested for many things, but NK cells weren't one of them. When I asked why, my RE didn't think they played as big a role as the other things they tested for (the names of which now escape me). Idk what the right answer is on that one. But I also know of other fellow bloggers who had high NK cells, went on treatment for them, and subsequently had healthy pregnancies. That leads me to believe there actually is something to high NK cells being "bad guys."

    As for diet, I've been dairy free for 5 years due to both vegetarian lifestyle and lactose intolerance. I might have dairy every few weeks and When i do, need to take the enyzmes like you. 5 years of no dairy and still no baby... My thoughts on dairy, gluten, whatever is everything in moderation. Unless you have bona fide celiac disease, it's doubtful that gluten is keeping you from getting pregnant.

    I hope you find the right combination of foods soon and that you don't have celiac disease .

    1. I'm not in a rush to ever go back to that gastro doc, I'm thinking of writing him a really bad review online too! Yes I've also followed lots of bloggers who got treatment for high killer cells and it seemed to do the trick. It's possible it would have worked anyway but I've seen it happen so often I really think there must be something to it. For some people anyway. I don't have celiac disease which is a relief!

  6. If I were you, I think I'd be willing to try out the intralipids. Being infertile does make you pretty desperate and I like that one article pointed out that we are soft targets. We definitely are as most of us will try anything. But, once you've tried everything else, it's hard not to do the one thing you have left. I definitely think you should talk to your doctor and see what all it entails.(Did you check out the YouTube video I sent you?)

    As for Celiac, I think it's great that you're getting tested! I was tested about 15 years ago and the results came back "borderline" positive. But, I was a teenager and didn't want to stop eating yummy food so I ignored it and continued eating what I wanted to. About a year into ttc, my sister mentioned that I shouldn't be drinking so much beer because of the gluten. That's when I started looking into Celiac and infertility. My gastro. told me that a blood test can miss the diagnosis and wanted to do an endoscopy, as well. Apparently, this is the only true way to know if you have Celiac. He told me that I'd have to take a few months off from trying for the procedure. I wasn't willing to do that so I just decided to make the lifestyle change. I've been gluten free for almost a year now and feel so much better. There is no cure or special pill for Celiac. It just requires a lifestyle change. (I do plan to have an endoscopy done in the future but wasn't willing to take time off from trying to conceive). If you do find out that you are gluten intolerant, let me know. I'll send you lots of good blogs and information for cooking. It's really not that bad at all. I have lots of recipes I enjoy. :)

    My research into Celiac says that it can cause DOR, low AMH, POF, and miscarriages. I have diminished ovarian reserve and was told that it's hereditary. But, no one in my family has ever had this nor have they had problems getting pregnant. This really makes me think that gluten is the problem. All those years I spent not caring about my borderline results... it makes me so angry to think about it! I just wish someone would have forced me to take it seriously.

    The only other possibility is mild endometriosis. If it is mild, it's possible that it's undetectable because I don't have symptoms. But, endo can/will cause low AMH, DOR, POF. Endo does run in my family so that is a possibility. But, my RE didn't think it was worth testing for because I didn't have symptoms and it wasn't going to change our plan to get a baby.

    Hopefully, you won't have Celiac Disease and your doctor will let you try out Intralipids. Screw your gastrologist for not knowing anything about the female body. I'm always so surprised when people in the medical field know less about certain issues than us common folks. You deserve better care than that!

    Keep us updated and let us know what you decide. I'm so sorry you're now facing this dilemma. I can't imagine how you must be feeling. Sending love and internet hugs!

    1. thanks for your message! I'm not celiac which is a relief but I think I might have some gluten sensitivity/intolerance sometimes so I'm going to try cutting back a bit anyway! And see if I notice any difference in how I feel. I wondered about endo too since it seems so common but I don't have any symptoms and I had a laparoscopy to remove a cyst two years ago and they didn't find any then.

      I'm definitely leaning towards trying the intralipids or whatever treatment is suggested, will try anything at this stage!

  7. Please allow me to tell you my story. I know so much about this now.
    I have not been down the ivf route as my situation is different.
    I fall pregnant with (I believe) healthy babies. However my elevated nk cells attack my pregnancies and I lose them at around 6/7 weeks. This happened 6 times in 2 yrs.
    The last 2 losses were while I was on nk therapy. I'd been told after the first 4 mc's by specialist mc clinic st mary's in Paddington that I was healthy, no problem with me and I will likely have a healthy prey next time.
    I then heard about nk cells and investigated.
    Found a private clinic, started treatment after having levels tested and the results showing high levels.
    2 pregnancies failed again at the same time. On both I had been on intralipid drips every 4 weeks, progesterone pessaries and injections, clexane injections, steroid tablets, aspirin.....
    Monitored closely but 2 more losses.
    Now 6 losses and feeling baffled as I knowwe were treating a proven problem and treating correctly.
    Someone mentioned nutritionist treatment so I spoke to someone. The nutritionist I met had treated another lady for exactly the same problem. Successfully twice.
    So we tested my food intolerances with a home blood test kit. Lorisian £300.
    It tests you for 150 foods to see it you are intolerant.
    I came back with reactions to yeast, dairy, corn maize, tuna, grapes, plaice, sole, lychees, peanut, eggs. Ironically foods I ate daily...I also did a candida quiz and showed high levels of candida.
    So 3 month detox of these foods. Alongside some gut healing tablets and tips, body brushing, Epsom salt baths etc.
    I went through a traumatic ordeal as a teen, I was diagnosed with ptsd, the theory is that high levels of stress can elevate nk levels as a ? Result of a leaky gut triggered by stress.
    I'm sure other ppl have them for diff reasons potentially but that's my cause ...
    So after my 3 month detox I'm now taking some candida cleanse tablets 1 HR before food, and a detox support tablet 1 HR after food. This is the next stage to kill of candida and remove it from my blood stream and body.
    So 4 months in now in total. Detoxing does feel a bit shit. Boring missing certain foods, and for this detox especially yeast, I also have to eat a very low sugar diet. Reason 1- yeast feeds on sugar/ 2- stable sugar levels are very good for fertility. Fluctuating sugar levels are a bad idea.
    The idea is that foods you may not realise you are intolerant to, but are eating are making you immune system respond as your gut is unhappy after you eat said foods. Bloating, fullness, discomfort, constipation, gas etc.. when your immune system is elevated, your nk levels jump up too as a natural removing the intolerances your immune system will relax and nk cells will natural decrease.
    Generally calming your body down.
    Since removing these foods that I was intolerant to I have rare bloating, less gas, less discomfort. I can see and feel very quickly if I've eaten something I shouldn't have now.
    It's. Implement because you have to know everything that contains your intolerant. Yeast for example is in sauces, stocks, ripe fruit, soy, vinegar.

    Please email me to chat directly if you'd like to discuss further.
    Regarding nk therapy. My personal opinion is that although nk therapy meds may work, if you are eating foods that are triggering an nk cell immune system response then your stuck in a vicious cycle.

    In January I can start trying again once my 4 month detox is fully done, then we retest my levels of nk cells and assess again.
    I will be sticking to this diet until I have baby safely in my arms to be on the safe side and ensure the nk cells don't jump up at all.

    1. Thank you so much for commenting and sharing your story. I am so sorry to hear about all your loses. Just heartbreaking.

      I also do think there could be a connection with some of my food issues and the elevated natural killer cells and I was disappointed the gastroenterologist I went to didn't take me seriously. I've started taking some extra strong probiotic tablets with 10 million healthy bacteria and generally watching which foods I react badly too and trying to avoid them and my digestion seems to have improved so far. I hope I won't need to cut out more food groups as it is so hard to be on a restrictive diet. You are great to keep it up!

      That is promising that the nutritionist was able to help other women with similar issues. I really hope this will do the trick for you and that your next pregnancy will result in a healthy baby. Wishing you all the best!


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