20 July 2018

Can your weight affect your fertility?

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Complete Fertility

People whose weight falls outside of what is termed healthy for their height may reduce their chances of conceiving and having a healthy baby.

These ‘unhealthy’ weight categories include being obese, overweight and underweight. In this blog we look at the problems associated with being over and underweight for both men and women when it comes to their fertility and, what you can do to optimise your fertility.

Why does having excess weight affect your chances of having a healthy baby?

With the rise in obesity and people being overweight in the UK, it’s important to understand the impact of excess weight on your fertility.

In both men and women, obesity and being overweight can affect fertility by causing hormonal imbalances.

For men, being overweight or obese can result in reduced sperm qualitycompared to men of a healthy weight and, it may be associated with a lower sperm volume, sperm count, concentration and motility and, more sperm defects. Men who are overweight can experience hormonal changes which may also result in a reduced interest in sex and problems getting an erection.

For women, excess weight can cause hormonal imbalances, irregular menstrual cycles or the absence of ovulation and, prevent fertility treatments from working.

Complications of IVF fertility treatment in overweight and obese women may include: fewer eggs being retrieved, an increased difficulty of retrieving eggs and embryo transfer, a greater anaesthetic risk during egg retrieval and, lower embryo implantation rates.

Polycystic ovary syndrome (PCOS) is one of the most common reasons for infertility in women. In addition to disrupting your regular menstrual cycles, PCOS may also affect your ability to lose weight and can be the cause of a self-perpetuating cycle.

Being an overweight woman may also increase your risk of pregnancy associated complications such as miscarriage, gestational diabetes and hypertension. Babies born to overweight mothers are at an increased risk of neural tube defects such as spina bifida, heart defects and, obesity, type 2 diabetes, and high cholesterol.

Why being underweight may affect your fertility

Being underweight can reduce a man’s sperm quality compared to men who are a healthy weight.

In women, being underweight can reduce your fertility. Hormonal imbalances, due to the production of too little of the female hormone oestrogen can lead to irregular or no menstrual periods in underweight women.

Also babies born to mothers who are underweight are at higher risk of premature birth or low birth weight.

What is a healthy weight?

Most often the Body Mass Index (BMI) is used to calculate whether you’re a healthy weight for your height. It offers an index range for normal weight, overweight or obese and underweight. A healthy BMI is considered to be between 18.5 and 25.

What can you do to optimise your fertility?

It is recommended that you try to achieve a healthy BMI and, enjoy a healthy lifestyle and diet to optimise your fertility. Often couples who engage in behaviour to reduce their BMI together have more success as they can encourage and support each other in achieving their BMI goals.

Support at Complete Fertility

Here at Complete Fertility we offer a preconception programme as part of our ‘Programme for Pregnancy‘. You will have an individual consultation with one of our specially trained nurses who will draw up a personal profile with you and the factors you may be able to influence to improve your chances of conceiving with and without fertility treatments.

This proactive approach can help you make changes to your diet and giving up smoking, factors that may impact on gamete quality, implantation, pregnancy and, you and your baby’s health. It emphasises the importance of a healthy diet and weight prior to conception for fertility success.

For more information about our Programme for Pregnancy, call us on 023 8120 6980 or email info@completefertility.co.uk.

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