What is BMI and why is it so important when it comes to fertility?

Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. BMI is calculated by dividing your height (in centimetres) by your weight (in kilograms).  So for example, if you are 173cm tall and weigh 67 kgs your BMI would be 22.4. Which is within the normal range.

The same groups apply to both men and women. Underweight: BMI is less than 18.5. Normal weight: BMI is 18.5 to 24.9. Overweight: BMI is 25 to 29.9. Obese:BMI is 30 or more.

What is the maximum BMI you would allow for fertility treatment?

We treat women with a BMI up to 35.  However, we would advise that if you do have a BMI of 30+, that being overweight can negatively affect your fertility. At HART, we don’t just focus on “diagnosed” fertility issues, we also look at lifestyle and factors that could affect your treatment outcome. And so weight issues and bad lifestyle choices could have a negative affect on your fertility overall.

How does a high BMI affect fertility treatment?

A high BMI causes issues in IVF (In Vitro Fertilisation), ICSI (Intracystoplasmic sperm injection) or IUI (Artificial Insemination) treatment just as much as it would do in natural conception, because of how it affects your fertility.

Women with a high BMI have lower success rates from IVF, it can also affect how you respond to fertility medications and the quality of your eggs. Women with a high BMI also have a higher risk of pregnancy complications.

BMI isn’t just an issue for women undergoing fertility treatment however. It’s just as important for your partner too. If he’s significantly overweight, it can affect sperm. Studies have shown that obesity can affect sperm motility (how well sperm moves) with a higher risk of sperm DNA damage. A high BMI can also affect sperm count.

It is therefore very important to ensure that both you and your partner are really focused on a healthy lifestyle before you start fertility treatment. So if you already have a high BMI, we would always recommend first that you get your diet on track and you start an exercise regime before commencing treatment.

Our fertility nutritionist Emily Innes provides private consultations for our patients who wish to reduce their BMI before fertility treatment.  She provides our patients with a personally tailored plan and practical advice to help you achieve your fertility goals!

Will my lifestyle affect whether IVF will work for me?

We know that a healthy diet  and BMI has an impact on IVF success rates, but other factors such as smoking and alcohol abuse also play significant roles too. Bad lifestyle choices will always affect fertility in both men and women.

Various studies have shown a link between alcohol intake and conception – it’s why women planning a pregnancy are advised to limit alcohol (or cease completely). In men, excessive alcohol intake can negatively affect sperm quality, quantity and testosterone levels.

If you smoke, studies have shown that it reduces the chances of conception. For men, it can decrease sperm count and motility and affect sperm shape and function.

We would therefore advise that if you do smoke (or if your partner smokes) that you quit at least three months before you start treatment. We know this is extremely tough for some but it is important to ensure that your bodies (physically, physiologically, hormonally, emotionally), not to mention your eggs and sperm, are in the best possible state when commencing fertility treatments.

What can I do to improve my fertility before I start IVF, ICSI or IUI?

As mentioned above, adopting a healthy lifestyle in the months before you start fertility treatment is your first step.

Seek advice from our Fertility Nutritionist, Emily Innes who can put you on the perfect plan that will suit your body. Be sure to eat a good balanced diet that will provide you with all the vitamins and minerals you need, such as wholegrain carbs, lean proteins and omega-3 rich fish with plenty of fruit and vegetables.

De-stress by starting yoga!  Fertility concerns and or problems can be hugely stressful on not only your body but on your overall well-being.  It is therefore important that during this time of preparing yourself for fertility treatment that you have time to de-stress, breathe and find your own zen! We have a wonderful Fertility Yoga Specialist, Harriet Came who is a peri natal yoga specialist with experience and great passion for supporting couples on their fertility journey.

Finally, come in and see us!  We have an incredible team of Fertility Experts who will advise you on what steps are important to make your dream of starting a family, a reality.

Love HART x