Pregnancy / 28 August, 2025 / Ellie Thompson
In the UK, many fertility clinics still use BMI as a strict criterion for IVF eligibility—but evidence from other countries tells a different story. Patients with higher BMIs are achieving successful outcomes elsewhere, raising questions about whether BMI should really limit access to treatment.
Dr. Jyoti Taneja, FRCOG, DFSRH, a leading consultant in Obstetrics and Gynaecology specialising in Reproductive Medicine and Surgery at IVF clinic Avenues in London, shares her expertise on why a more individualised approach can make all the difference for patients seeking IVF.
I meet many people who have already been told “no” before they reach us. In the UK, there is no law that sets a BMI limit; however, some clinics and funders establish their own cutoffs to manage perceived risks or allocate resources. The problem is that a single number cannot capture someone’s health or their chance of success. With proper planning, many patients with higher BMIs can be treated safely. Our job is to look at the whole person and say, “How can we help?” rather than, “You do not fit.”
How reliable is BMI as a predictor of IVF success?
BMI is a rough population marker, not a crystal ball for an individual. Two people with the same BMI can have very different ovarian reserve, embryo quality, uterine health and response to medication. That is why we do not make decisions on BMI alone. We assess the complete reproductive picture and then design a plan around you.
What does the research say about outcomes for higher BMI?
Broadly, higher BMI is linked to some increased risks, but it does not mean you cannot have a successful IVF journey. Many people with higher BMI conceive and have healthy babies, especially when care is personalised. In our own lab analysis, we did not see a simple straight-line relationship between BMI and egg quality. Many patients with a BMI above 30 produced high-quality oocytes. That mirrors what we see in everyday practice when protocols and lab standards are strong.
How can clinics focus on quality of care rather than BMI?
Quality comes from process. Start with a thorough pre-assessment, optimise any health factors we can, plan anaesthesia properly, and keep the lab consistent and data-driven. At Avenues we also use AI tools in the lab to support decision-making. These steps help everyone, and they remove the temptation to use BMI as a shortcut for access.
What role do bespoke treatment plans play?
A bespoke plan is the difference between exclusion and safe access. We adjust stimulation, medication dosing, and day-of-procedure support to your physiology, not your BMI category. It is thoughtful, it is safer, and it is kinder. Patients feel that care has been designed for them, because it has.
Are there specific risks for higher BMI, and how are they managed?
Some risks are more common, for example, airway challenges with anaesthesia or pregnancy-related conditions like hypertension and gestational diabetes. These are manageable when you plan for them. We conduct a detailed pre-assessment, have the right equipment and team, and provide you with a briefing on how we will ensure your comfort and safety on the day. Risk management should be a pathway, not a barrier.
How can patients advocate for themselves if BMI is used as a barrier?
You deserve an individual assessment. A simple script helps:
“Please assess my personal risks and options rather than BMI alone.”
“If you cannot treat me, what would need to change for you to say yes? Please note that in my record.”
“Can you provide a referral to a clinic that offers weight-inclusive care?”
Bring a partner or friend, write down your questions, and do not be afraid to seek a second opinion. Our Hospitality Team can help you prepare for those conversations.
What can the UK learn from places where BMI is not a barrier?
The lesson is to invest in safer pathways rather than smaller eligibility lists. When clinics focus on individual risk, good pre-assessment and consistent lab practice, access widens without compromising safety. Patients feel seen, and outcomes improve because care actually fits the person.
How can clinics move from “one-size-fits-all” to personalised care?
Build a standard pathway for personalisation. That sounds like a paradox, but it works. Use structured baselining, decision checklists, anaesthesia planning for different bodies, and clear consent that explains risks and mitigations. Add technology that supports consistency. Then make space for coaching and emotional support, because feeling safe and informed changes how you move through treatment.
What guidance or support is currently available?
Start with a clinic that will evaluate you, not just your BMI, such as Avenues. Our team shares practical resources on preparing for appointments. We offer a Fair IVF+ Package, which has no BMI restrictions and includes Nicola Salmon’s coaching, providing tools for confidence and calm. At Avenues, you are not doing the fertility journey alone.
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