If you’ve experienced the heartbreak of recurrent losses or failed IVF transfers despite high-quality embryos and “normal” test results, you’re not alone—and you’re not imagining that something deeper might be going on.
Many of the women and couples I work with arrive feeling confused, defeated, and dismissed by conventional fertility care. They’ve done everything right — IVF cycles, supplements, dietary changes — and still haven’t achieved or maintained a pregnancy. One often overlooked reason? Immune system dysregulation.
Your immune system is designed to defend your body from foreign invaders. But a developing embryo — especially one created with IVF — is partially made up of DNA that is foreign to the mother’s body. If the immune system fails to shift into a more tolerant, pregnancy-supportive state, it can misidentify the embryo as a threat and interfere with implantation or trigger a loss.
When the Immune System Disrupts Fertility
We now understand that a well-functioning immune system must walk a delicate line during early pregnancy: protecting you from illness while not rejecting the embryo. If this balance is off, it can be nearly impossible to establish or maintain a healthy pregnancy.
Some key immune dysfunctions that may play a role include:
- Elevated Natural Killer (NK) Cells
While the name sounds alarming, NK cells are a normal part of your immune defense. However, in some cases (especially in women with unexplained recurrent pregnancy loss), these cells become overactive or overly abundant, particularly in the uterus. This can create a hostile environment that prevents implantation or causes the embryo to be rejected shortly after. - TH1/TH2 Cytokine Imbalance
A healthy pregnancy requires a shift toward an anti-inflammatory (TH2-dominant) immune response. If your immune system is skewed toward a TH1 (pro-inflammatory) state, it may not allow implantation to succeed or it may contribute to early pregnancy loss. This imbalance can also impact the success of IVF, even with high-grade embryos. - Autoimmune Activity
If you have underlying autoimmune tendencies (e.g. thyroid antibodies, lupus markers, antiphospholipid antibodies), your immune system may be predisposed to attack tissues in your own body, including those involved in early pregnancy, such as the trophoblast and placental interface. This increases the risk of chemical pregnancies, early miscarriages, and even late pregnancy complications.
Signs Immune Dysfunction May Be Affecting You
• Two or more consecutive miscarriages (even at early stages)
• Repeated IVF or IUI failure, despite good-quality embryos
• “Unexplained” infertility with no clear hormonal or anatomical cause
• History of autoimmune conditions (Hashimoto’s, lupus, RA, etc.)
• Family history of autoimmunity
• Chronic inflammatory symptoms (joint pain, fatigue, IBS, rashes, allergies)
How We Test for Immune Factors in Fertility
While conventional fertility clinics rarely explore these immune factors, a comprehensive reproductive immunology workup may include:
• Uterine NK cell biopsy or peripheral blood NK activity
• Cytokine panels (including TH1/TH2 ratios, TNF-α, IL-6, IL-10)
• Autoimmune antibody screening (TPO, TG, ANA, antiphospholipid antibodies)
• High-sensitivity CRP and other inflammatory markers
• Stool testing to assess gut-immune interactions and microbiome balance
This type of testing gives us a clearer picture of the immune landscape you’re working with—and opens the door to personalized, evidence-informed support.
What Can Be Done? – Restoring Immune Balance
Immune overactivation is not irreversible. The goal is not to suppress your immune system but to gently regulate and guide it toward tolerance and balance.
Some tools we may incorporate:
• Anti-inflammatory diet and gut support to reduce immune triggers at the root
• Nutraceuticals (e.g. omega-3s, curcumin, quercetin, vitamin D, NAC)
• Targeted probiotic support to influence gut-immune signaling
• Low-dose naltrexone (LDN) to modulate autoimmune responses
• Intralipid IV therapy to calm uterine NK activity and support implantation
• Acupuncture to promote neuroimmune regulation
• Stress reduction techniques, since psychological stress directly affects immune behavior
The goal is to create a receptive uterine environment, support healthy placentation, and dramatically improve the chances of successful implantation and pregnancy.
If you’ve experienced the devastation of multiple losses or failed embryo transfers, you need more than reassurance—you need answers.
Reproductive immunology offers a roadmap to uncover what might be silently undermining your efforts—and it opens new treatment avenues that traditional protocols may have missed entirely.
If this resonates with your story, we’re here to help.