Age Limit & BMI Criteria

Infertility is defined as the failure to conceive after one year of having regular unprotected intercourse, or failure to conceive after six months of regular unprotected intercourse in circumstances where couples have managed to conceive in the past. The World Health Organisation (WHO) estimates that 1 in 6 couples may be affected by subfertility, though some experts believe this number may be higher.

There are many reasons you and your partner may be having trouble conceiving naturally, and at GENNET City Fertility we will do everything we can to uncover the reasons that are preventing you from taking the next step towards becoming parents. Some of these factors may be related to your age or your BMI and weight, which we have our own criteria for assessing and advising on before treatment begins.

Read on below to learn more, or contact us today if you would like to speak to one of our members of staff about booking a consultation.

Our Age Limit at GENNET City Fertility

As we are a private clinic, the treatments we will provide for our patients are not limited by their age, as they might be in an NHS setting. We are more than happy to support a higher age threshold for those looking to start the journey to parenthood a little bit later in life; this includes offering alternative methods of treatment for those who are approaching or have already reached those thresholds.

We will be glad to offer treatment for female patients, or for non-binary or transgender patients who were born female, from 18 years of age up until their 46th birthday. This is an additional six years beyond the age threshold offered by most NHS trusts, so you can take the time you need to prepare and get ready for the next step in forming the family you’ve always wanted.

For patients above this threshold, our consultants will also be able to offer information and advice on egg donation and surrogacy as options. Regardless of your age at the time you choose to start treatment with us, we will always be open, honest, and transparent about the likelihood of success and what we can do to help.

We believe that it is your right to choose your treatment from the options we have available. As such, we encourage all of our patients to make fully informed decisions about what they would like from us, and to let us know which treatment option they feel is best for them.

There are no age limits or restrictions for male patients, or non-binary or transgender patients who were born male.

Our BMI and Weight Criteria at GENNET City Fertility






Normal weight




Obese-Class I


Obese-Class II

40 and above

Obese-Class III


We would discourage patients from moving forward with treatment if their BMI is over 35kg/m2. This is because BMI above this weight causes a significant reduction in the chances of a successful treatment, as well as increases in risks to both the patient going through the pregnancy and their baby. For these patients, we would strongly recommend speaking to their GP or to a professional dietician, in order to reduce their weight.

In any and all cases that treatment is refused because of a patient’s BMI, we will arrange follow-ups on three or six month bases in order to assess their weight loss. We will also offer counselling and support where needed or requested.

For Patients with BMI of 32 to 35

We will be able to offer treatment for patients with BMI ranging between 32 and 35, but we must also note that they will be assessed on an individual basis. For example, we may need to take underlying conditions, such as hypertension or diabetes, into consideration when thinking of potential risks to the pregnancy. Patients may also need to be referred for medical assessment before we can move forward with their treatment.

At GENNET City Fertility, we are able to provide support for patients looking to make dietary and lifestyle changes that may lead to them reducing their weight. Through Tailor Made Nutrition and the services supplied by Dr Michelle Braude, our patients can receive expert guidance and support that has been optimised to suit their needs. With this counselling on their side, our patients are more likely to make the changes they need to take the next step that little bit sooner sooner.

Our Partnership with Counterweight

We are also working with Counterweight to provide our patients with the advice and assistance they need before they start their own IVF treatment cycles. This simple, three-step programme is designed to assist our clients not only with reducing their weight, but also avoiding the “yo-yo” effect by keeping their weight down permanently. 

If you would like to learn more about this programme, please follow the link above and fill out the contact form found at the bottom of the page. A specialist dietician will soon be in touch to provide you with more information.

Contacting Us

If you have any further questions about our age limits or weight criteria, please don’t hesitate to get in touch with our clinic on the phone or via an email. Our friendly staff will be happy to explain anything that needs clarification, or offer answers to any queries.

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