Natural Killer Cells, Fertility and Miscarriage
If you’re struggling with infertility or recurrent miscarriage you need to know about Natural Killer Cells.
Natural Killer cells are cells in our bodies that we need to get rid of things that might cause problems in the body, eg. tumors. However when these NKC are at increased levels in the uterine lining or endometrium (and there is controversy over what increased is because they numbers differ significantly in different parts of the cycle) they might be actually mistaking the embryo for a foreign body and attacking it ie not allowing it to implant. However more needs to be learned about the NKC in the uterine lining because it does appear to be different than the NKC in other parts of the body, and therefore what actually happens is unknown and maybe much more complex or simplified than what researchers now think.
If levels of NKC do create issues for fertility it can be hard to understand how and why your own body may be attacking its own tissue, i.e. the fertilized egg.
Remember, the immune system’s response is meant to get rid of foreign invaders in your system to keep you healthy. If your body looks at the fertilized egg as a foreign invader then it may try to get rid of it. In some cases because the embryo wouldn’t have survived or it has a chromosomal defect the body will let go of the pregnancy for this reason.
Elevated Natural Killer Cells in the endometrial lining may be an issue for you if you have had recurrent miscarriages or many missed conceptions (fertilisations that just don’t seem to take), or several IVF attempts where you seem to produce good quality embryos but they just don’t implant.
To test this theory some doctors are doing biopsies of the endometrial lining to assess NKC activity. If elevated, then medicine can be administered either with an artificial cycle or right when a natural pregnancy is detected to suppress the activity of the NKC long enough for the embryo to implant.
We have found that not all doctors know about this/use these protocols and many that do know about it are skeptical that it is even an issue.
We would suggest you talk to your fertility specialist about this issue to see what their thoughts are if you have had several IVF cycles with good embryos but no implantation, recurrent miscarriages or long cycles where your temps are elevated past the normal 14 day luteal phase but then drop out and you begin menstruating 16, 17, 18 days post ovulation.
If they do the testing and it turn out to show elevated levels or Natural Killer Cells in the uterine lining, your Doctor may use treatment to address the issue, but naturally you may be able to assist as well.
Keep in mind though if NKC are tested from the uterine lining that research has shown that at certain times of the cycle, the NKCs are normally elevated. So, if you have a positive test or a test that says the Natural Killer Cells are elevated, make sure you discuss this with your doctor to confirm that at when you had the test done, this wasn’t at the time that NKCs are normally increased in the uterus OR that if done at that time, your results are higher than what they should be for that time in the cycle. Because if they are looking at levels typically normal for the first half of the cycle but you were tested in the second half this can create some confusion as to whether or not your test results were truly elevated.
Can Progesterone Help With NKC Activity?
Progesterone has been considered nature’s own immunosuppressant for years. Meaning if there is enough progesterone available there the NKC activity may not be an issue.
Monitoring your progesterone levels can be done with testing such as blood and saliva tests but we also use temperature charting to help give us some indication about what may be happening with this too.
If your progesterone levels are determined to be low then this may be an important area to address to help with eleveated NK cells.
Other hormone glands in your body ie your thyroid and your adrenals both have an impact on progesterone production. This is because the hormones they release ie T3 and cortisol respectively can have a direct impact on progesterone. This means making sure that these parts of your body are functioning at their best is really important.
Probiotics For Uterine Health
Recent research has shown that despite what researchers used to think, the uterus is not a sterile environment, meaning there are bugs present that make up a uterine microbiome. You often hear about this related to the gut but many areas of the body has its own microbiome. The gut, the skin, the vagina, the uterus, etc.
So, there is potential that if the uterine microbiome has an imbalance between good and bad bacteria there may be a reaction from the body’s Natural Killer Cells making them respond to the imbalance and therefore increasing NKC’s activity. More research needs to be done in this area. But a probiotic taken orally has many other benefits if it is accompanied by a healthy eating plan, that this might be a useful addition to your supplementation regime.
Probiotics inserted vaginally may also be a benefit however the research there does support utilising certain strains of probiotics vaginally for bacterial vaginosis so there is certainly promise to their use for uterine health as well.
To book an appointment with our Naturopath to discuss steps you can consider if you have been diagnosed with high NK cells go to: www.naturalfertility.co./book-now
Here at Natural Fertility Co we have been helping patients with their fertility and hormone health for over two decades. If you would like to book your first consultation with us then please go to our booking page.