Reproductive immunology testing

What is reproductive immunology testing?

Reproductive immunology testing is a group of tests that some private clinics offer to people who have had miscarriages or failed IVF, based on the idea that the immune system is rejecting the pregnancy or embryo. The best-known is natural killer (NK) cell testing, done either on a blood sample or on a small piece of the womb lining.

These tests are usually offered alongside proposed 'immune treatments' such as steroids, intralipid drips, intravenous immunoglobulin (IVIG) and TNF blockers (for example, Humira/adalimumab).

Vuemedics's position follows UK regulators and specialists. The Human Fertilisation and Embryology Authority (HFEA) and the Royal College of Obstetricians and Gynaecologists (RCOG) advise against these tests and treatments outside formal research trials, because there is no good evidence that they work, and some of the treatments carry real risks.

This guide exists mainly to protect you. If a clinic is recommending NK cell testing or immune treatments to improve your chance of a baby, that should be treated as a warning sign, and you should ask hard questions before paying or starting treatment.

Types, options & approaches

There may be different ways to do this. The right approach depends on the clinical question and your circumstances.

What the regulators say

Source: HFEA treatment add-ons information. These are not part of routine NHS care, and the immune treatments can cause harm.

Preparing for your test

• Before agreeing to any test, ask why it is being recommended and what the result would change.
• Ask whether the test and any treatment are supported by good evidence, and whether they are offered on the NHS (they are not, as routine care).
• Ask to see independent information, such as the HFEA traffic-light ratings for add-ons.
• Consider getting a second opinion, ideally from an NHS recurrent miscarriage or fertility specialist.
• Find out the full cost, including the proposed treatments, before committing.
• If you are grieving repeated losses, take someone with you and do not feel pressured to decide on the day.

What happens

If you go ahead, a blood sample is taken, or a small biopsy of the womb lining is performed in clinic. The sample is sent to a laboratory to count immune cells or measure other markers.

The clinic then usually explains the result as showing 'high' or 'abnormal' immune activity and proposes a treatment to suppress it, such as steroids, an intralipid drip, IVIG or a TNF blocker.

Because the underlying theory is not well supported and the normal ranges are not agreed, these results are difficult to interpret. A 'high' NK cell result does not reliably predict miscarriage or IVF failure, and treating it has not been shown to improve the chance of a baby.

Is this test right for me?

A good consultation should explore whether it's the right choice for you now — including reasons to wait or consider something else.

Before you decide

Use this as a shared-decision checklist. The aim is not just “can this be done?”, but whether it is right for you, now, with the risks and alternatives clearly understood.

The key point is that the risks here are real while the benefit is not established. The HFEA states there is no evidence that immune cells, including uterine NK cells, prevent pregnancy, and 'no reason for any patient without an immunological disease to take these therapies'. If you are offered these tests or treatments, ask for the evidence in writing and seek a second opinion before paying or starting.

Published figures to discuss

Reliable numbers for benefit do not exist, because good-quality trials have not shown that these tests or treatments improve the chance of a baby. The risks of the treatments are real but vary by drug and dose. We therefore avoid quoting success or risk percentages and instead point to the regulators' position.

These are literature figures, not a personalised prediction. Your own risks and likely benefits depend on your circumstances, your health, and how your care is carried out and followed up.

What happens afterwards

There is no physical recovery from a blood test, and only brief cramping from a womb-lining biopsy. The more important 'afterwards' is making sense of a result that is hard to interpret, and not being pushed into treatment you do not need.

• Feeling unsure how to interpret an 'abnormal' immune result
• Feeling pressure or hope around a proposed treatment
• Wanting a second opinion before deciding
• Mild cramping or spotting after a womb-lining biopsy

Aftercare

• Do not start immune treatment without understanding the evidence and the risks.
• Ask for the result, the normal range and the evidence in writing.
• Seek a second opinion from an NHS recurrent miscarriage or fertility specialist.
• If you have had repeated miscarriages, ask about the evidence-based RCOG investigation pathway instead.
• Look after your emotional wellbeing and consider accredited fertility counselling.
• Report any side effects from treatments promptly, and seek urgent help for severe reactions.

• Written reason for the test and what it would change
• The evidence for any proposed treatment, in writing
• Full cost of tests and treatments
• A second-opinion appointment booked if unsure
• Information on the evidence-based recurrent miscarriage pathway
• Support contact (charity or accredited counsellor) noted

⚠ Get urgent help if…

• A clinic recommending NK cell testing or immune treatments as routine, or guaranteeing they will help
• Severe allergic reaction during an infusion (difficulty breathing, swelling, rash) — this is an emergency, call 999
• Signs of a blood clot after IVIG (swollen, painful calf or sudden breathlessness)
• Signs of infection while on steroids (fever, feeling very unwell)
• Feeling pressured to pay for or start treatment on the day, without time to consider
• Feeling unable to cope or having thoughts of harming yourself

Who to contact: your clinician, clinic or test provider first (keep their number to hand). For urgent advice when you can't reach them, call NHS 111. In an emergency, call 999.

General guidance — it doesn't replace the specific advice your specialist gives you.

Results & realistic expectations

There is no result from these tests that can be relied on to predict miscarriage or IVF failure, or to guide treatment that improves the chance of a baby. A 'high' NK cell level, in particular, does not reliably mean anything about your pregnancy chances, because blood NK cells differ from womb-lining cells and the normal ranges are not agreed.

The most useful outcome of considering these tests is an informed decision to follow the evidence-based pathway instead, and to protect yourself from unproven, sometimes risky, treatment.

Because these tests are not supported by good evidence, there is no meaningful 'shelf life' to a result. If you have had repeated miscarriages or failed IVF, your time and money are better spent on the evidence-based recurrent miscarriage or fertility pathways, which can be repeated or reviewed appropriately.

Related tests, treatments or support

These tests are often bundled with other unproven IVF 'add-ons'. The HFEA publishes a traffic-light rating system for add-ons, and most immune tests and treatments are rated as having safety concerns or insufficient evidence. Be cautious about packages that combine several unproven extras.

Follow-up & long-term care

If you have been offered or have had these tests, a good next step is a follow-up with an NHS recurrent miscarriage or fertility specialist who can explain the evidence and offer the standard investigation pathway. Any clinic offering immune treatment should be able to give you, in writing, the evidence for benefit and the risks involved.

Repeat, follow-on and what comes next

• Because the tests are not reliable, 'abnormal' results are often repeated or used to justify further paid treatment.
• Stopping these treatments and moving to evidence-based care is a reasonable and common decision after a second opinion.

Ask what happens if the result is unclear or needs repeating, and what is included if further tests or follow-up are needed.

What good aftercare looks like

• Honest, written information about the lack of proven benefit and the real risks.
• A clear route to a second opinion and to the evidence-based recurrent miscarriage pathway.
• Emotional support and accredited counselling for the impact of repeated loss or failed treatment.
• Prompt management of any treatment side effects, with emergency advice for severe reactions.
• No pressure to continue unproven treatment.

What affects the cost

Costs vary a great deal between people and providers, and we don't publish prices. What matters is understanding what drives the cost and making sure your quote is complete. The main things that affect it:

• Which tests are done (blood NK test, womb-lining biopsy, other immune panels)
• Whether proposed treatments (steroids, intralipid, IVIG, TNF blockers) are added, which can be expensive
• Number of clinic visits and infusions
• Repeat testing during or between cycles
• Whether these are bundled with other unproven IVF add-ons

• The evidence, in writing, that the test or treatment improves the chance of a baby
• The full cost of the test and any proposed treatments and infusions
• Whether the clinic relies on this result to justify further paid treatment
• What the HFEA traffic-light rating is for each add-on offered
• What happens, and what it costs, if results are 'abnormal'
• Whether an NHS or evidence-based alternative has been discussed

On the NHS? These tests and treatments are not part of routine NHS care and are advised against outside research; the NHS instead offers the evidence-based recurrent miscarriage investigation pathway. How you access NHS fertility and recurrent miscarriage services, and what you qualify for, is decided separately in each part of the UK — England, Wales, Scotland and Northern Ireland each have their own rules, which can differ and change over time. National clinical guidance (such as NICE for England) sets out what is recommended, but it does not by itself decide what is funded where you live. Ask your GP or the relevant NHS or HSC fertility service to confirm what is currently available to you.

You're entitled to your total cost in writing — including reports, follow-up and what happens if the result is inconclusive — before you decide.

Consent traps and marketing red flags

These are not small details. They are often where patients lose choice, time to reflect, or realistic expectations.

Choosing a specialist safely

• Check the specialist is on the GMC Specialist Register for this area.
• Make sure they work at a CQC-registered service, and look for membership of the relevant Royal College or professional body.
• You're entitled to time to consider and to have your questions answered before you agree — the specialist who looks after you should explain it, not a salesperson.
• Be wary of pressure: time-limited offers or deposits taken before you've had time to think are red flags, not bargains.
• You're entitled to your total cost in writing — including any follow-up — before you decide.

How Vuemedics verifies every consultant →

Take this to your consultation. A good specialist will welcome every one of these.

• What is the evidence that this test improves my chance of having a baby?
• Is this test or treatment recommended by the HFEA or RCOG, or only offered privately?
• What is the normal range for this test, and how reliable is it?
• What are the risks of the treatment you are proposing?
• What does the HFEA traffic-light rating say about this add-on?
• Would the evidence-based recurrent miscarriage pathway be more appropriate for me?
• Are you on the GMC Specialist Register for this area, and which Royal College or professional body are you a member of?
• Will you be the specialist who carries out my test, and who looks after me afterwards?
• What are the risks for someone like me, and how often do your own patients have a problem or need it repeated or redone?
• What does a realistic result look like — and what can this test not achieve?
• What are my options, including waiting, doing nothing for now, or choosing a different approach?
• Can I have written information, results and aftercare instructions in a format I can use, including any accessibility or communication support I need?
• What is the total cost in writing, including any follow-ups, and how much time do I have to decide?

Find a verified specialist for reproductive immunology testing

Every consultant is GMC-checked and independently reviewed. Search by postcode and distance, or switch to a map. Ordered by rating, relevance and recency — never by who pays.

How we made this page

Medically reviewed by a GMC-registered consultant. Written in plain English, checked against NHS, NICE, GMC and relevant Royal College / specialist-society guidance, and kept under review. No clinic paid to appear on this page, and we publish no pricing. This is general information to help you prepare — it is not a substitute for advice from your own clinician. How we review our guides →

Source hierarchy: UK regulator and NHS/NICE guidance first, then relevant Royal College or specialist-society guidance, then peer-reviewed evidence for procedure-specific figures where available.

Sources & standards: HFEA — Immunological tests and treatments for fertility HFEA — Treatment add-ons with limited evidence RCOG — Recurrent miscarriage (patient information) RCOG — Recurrent Miscarriage (Green-top Guideline No. 17) First do no harm: uterine natural killer (NK) cells in assisted reproduction (review, PMC) NICE NG257 — fertility problems: assessment and treatment (clinical guidance, England) NHS inform (Scotland) — infertility and fertility services NHS Wales — specialist fertility services commissioning policy (CP38) Northern Ireland Regional Fertility Centre (Belfast HSC Trust)

Reviews reflect patients' experience of care, not clinical outcomes. For procedure volumes and outcome data see PHIN.

Last medically reviewed 2026-09-21. Spotted something wrong or out of date? Report an error in this guide.