Could the air you breathe affect your chances of IVF success? New research has found a concerning link between poor air quality – including smoke from wildfires – and lower pregnancy rates following embryo transfer. Here’s what fertility patients need to know.
When you’re going through IVF, there can already feel like an overwhelming number of things to think about.
Medication. Food. Exercise. Sleep. Alcohol. Caffeine. Supplements. Stress.
But there’s another factor researchers are increasingly investigating:
The air we breathe.
A new study has found an association between unhealthy air quality and significantly lower pregnancy rates following IVF embryo transfer.
The research looked at patients undergoing fertility treatment in New York during the summer of 2023, when smoke from huge Canadian wildfires travelled hundreds of miles across the border and blanketed New York City.
And the results have raised important questions about the possible relationship between air pollution, wildfire smoke and fertility treatment.
What did the IVF study find?
Researchers looked at 190 fresh and frozen embryo transfers carried out at a fertility centre in New York between June and July 2023.
They compared IVF outcomes with the Air Quality Index (AQI) on the day each embryo transfer took place.
AQI is a measure used to show how clean or polluted the outdoor air is.
The researchers divided air quality into three groups:
Good air quality – AQI 0–50
Around 62% of embryo transfers resulted in a clinical pregnancy.
Moderate air quality – AQI 51–100
Around 65% resulted in a clinical pregnancy.
Unhealthy air quality – AQI above 100
The clinical pregnancy rate fell to approximately 27%.
That difference understandably attracted researchers’ attention.
But there is a really important point for anyone currently going through IVF:
The study found an association. It does not prove that wildfire smoke caused the embryo transfers to be unsuccessful.
More research is needed.
Why could wildfire smoke potentially affect fertility?
Wildfire smoke isn’t simply the smoke we can see or smell.
It can contain extremely small particles known as PM2.5 – particulate matter measuring 2.5 micrometres or less.
These particles are so tiny that they can travel deep into the lungs and potentially enter the bloodstream.
Researchers are investigating whether exposure to these particles could trigger inflammation and oxidative stress in the body.
Both are of interest in reproductive medicine because implantation – when an embryo attaches to the lining of the uterus – involves an incredibly complex interaction between the embryo, endometrium, hormones and immune system.
Scientists therefore believe it is biologically plausible that environmental pollution could potentially influence this delicate process.
But we don’t yet know exactly how, or how significant that effect may be.
Was the problem inside the IVF laboratory?
Interestingly, researchers don’t necessarily think so.
Modern IVF laboratories have sophisticated air-filtration and environmental-control systems designed to protect eggs, sperm and embryos.
One of the researchers, reproductive endocrinologist Dr Randi Goldman, believes the possible effect may instead relate to the patient’s exposure to poor air quality around the time of embryo transfer.
That could include the days immediately before and after transfer.
This is important because an embryo doesn’t exist separately from the person carrying it.
Once an embryo has been transferred, implantation depends on a complex biological environment inside the body.
Researchers now want to understand whether external environmental factors – including air pollution – can influence that environment.
This isn’t the first study linking wildfire smoke and IVF
Other research has raised similar questions.
Researchers at Oregon Health & Science University studied fertility patients undergoing IVF around the time of Oregon’s devastating 2020 wildfires.
They found that exposure to unhealthy air quality during the period when embryos were developing in the laboratory was associated with patients having fewer blastocysts available.
A blastocyst is an embryo that has developed for around five or six days after fertilisation and reached the stage at which it may be transferred or frozen.
Importantly, however, that study did not find significant differences in pregnancy outcomes following embryo transfer.
And another much larger Australian study published in 2026 looked at 1,647 assisted reproduction cycles around the devastating 2019–2020 Australian “Black Summer” wildfires.
That research found that well-controlled fertility laboratories were able to maintain extremely low particle levels despite high outdoor pollution – and researchers did not find significant differences in egg numbers, fertilisation, embryo use, pregnancy or live birth rates.
So the scientific picture isn’t yet straightforward.
That’s exactly why further research matters.
Could air pollution affect sperm too?
Potentially.
Environmental fertility research isn’t only looking at women or embryo implantation.
Scientists are increasingly investigating how pollution and wildfire smoke may affect male fertility and sperm health too.
Research presented to the American Society for Reproductive Medicine has linked wildfire-smoke exposure with changes in sperm concentration and total motile sperm count.
Other studies have also suggested that exposure to particulate pollution before conception may affect sperm development and quality.
This matters because fertility is not solely a female issue.
Both partners’ health and environmental exposures can potentially play a role in conception.
Should you postpone an embryo transfer because of wildfire smoke?
This is probably the biggest question someone reading this while going through IVF will have.
And the answer isn’t simply yes.
The New York study’s researchers suggested that, in some circumstances, freezing embryos and postponing embryo transfer until air quality improves could be considered.
But delaying fertility treatment isn’t a small decision.
There may be medical, emotional, financial and practical consequences.
You also cannot predict exactly what the air quality will be several weeks or months later.
And importantly, this is currently an emerging area of research.
Do not cancel or postpone an IVF cycle or embryo transfer without speaking to your fertility specialist.
If severe wildfire smoke or very poor air quality is affecting your area, contact your clinic and ask what they recommend for your individual circumstances.
What can I do if I’m having IVF during poor air quality?
There are some sensible steps you can take to reduce your exposure when air pollution levels are particularly high.
Check your local Air Quality Index
Air-quality forecasts can tell you when pollution levels are elevated.
If wildfire smoke is affecting your area, check official local health and environmental guidance.
Spend more time indoors
When outdoor air quality is unhealthy, reducing the amount of time you spend outside can reduce exposure.
Keep windows and doors closed when advised to do so.
Consider indoor air filtration
A HEPA air purifier can help remove fine particles from indoor air.
If you already use an air purifier, check that the filter is suitable for fine particulate matter and has been replaced according to the manufacturer’s instructions.
Avoid adding other sources of smoke
Avoid smoking and second-hand tobacco smoke and minimise other sources of indoor air pollution.
Ask your IVF clinic
If you’re approaching egg collection or embryo transfer during a period of severe air pollution, speak to your fertility team.
Ask:
“Is the current air quality something I need to consider for my treatment?”
Your clinic can advise you based on your treatment stage and individual circumstances.
Don’t blame yourself for your IVF outcome
This is perhaps the most important message.
Research into environmental fertility factors can be incredibly valuable.
But it can also unintentionally create another thing for fertility patients to worry about.
IVF success or failure is influenced by many complex factors, including age, egg and sperm health, embryo genetics, diagnosis, uterine factors and sometimes factors medicine still doesn’t completely understand.
You cannot control the weather.
You cannot control a wildfire hundreds or even thousands of miles away.
And you certainly shouldn’t look back at an unsuccessful IVF cycle and wonder whether going outside on a smoky day caused it to fail.
This research does not tell us that.
Instead, studies like these help fertility scientists identify environmental factors that may deserve greater investigation.
Our environment and our fertility are increasingly connected
This research also forms part of a much bigger conversation.
Scientists are increasingly examining how the environment around us could influence reproductive health.
That includes:
- air pollution
- wildfire smoke
- pesticides
- endocrine-disrupting chemicals
- plastics and microplastics
- occupational exposures
- extreme heat
- lifestyle and environmental toxins
There is still a huge amount we don’t know.
But fertility isn’t separate from the rest of our health.
Our reproductive systems exist within our bodies – and our bodies exist within an environment.
Understanding those connections could eventually help fertility specialists develop better advice, better prevention strategies and potentially more personalised fertility treatment.
Going through IVF? Understand the factors that matter to you
If you’re preparing for IVF, it can be difficult to separate the things you can control from those you can’t.
That’s why good information matters.
On Babble Connect by IVFbabble, you can access tools and guidance to help you understand and plan your fertility journey – without adding unnecessary fear.
You can explore:
Fertility symptoms and testing
Understand symptoms and questions you may want to discuss with your doctor.
IVF treatment planning
Learn about the different stages of IVF and prepare questions for your fertility team.
IVF costs
Use the IVF Cost & Treatment Planner to understand the expenses that may form part of your treatment.
Fertility clinics and experts
Find and connect with fertility professionals who can advise you based on your own medical circumstances.
IVF success information
Understand what IVF success rates mean and some of the factors that can influence treatment outcomes.
Because fertility research is moving quickly – and you deserve information that helps you feel informed rather than overwhelmed.
Explore fertility guidance, tools and experts on Babble Connect by IVFbabble.
This article is for information only and should not replace individual medical advice. Do not delay, cancel or change fertility treatment because of air quality without discussing it with your fertility clinic.
