If you are overweight and trying to get pregnant, it can take you longer to conceive than someone of a healthy weight. For 10% of overweight women, it can prevent them from conceiving naturally and they will need fertility treatment to get pregnant.
This is because women who are overweight tend to have higher levels of the hormone oestrogen. An imbalance of this hormone can affect the menstrual cycle and prevent ovulation. As oestrogen is made in the fat cells, the more of these you have, the more oestrogen your body is likely to make and the less likely your chances of conceiving each month.
It is also common for overweight women to develop Polycystic Ovarian Syndrome (PCOS). This reduces fertility by affecting the ovaries, causing them to develop cysts, not release eggs and produce high levels of male hormones.
Being overweight doesn’t just affect the chances of conception. Once pregnant, overweight women have a higher risk of miscarriage, gestational diabetes and pre-eclampsia.
The developing baby is also affected by the mother’s (and the father’s) weight. Babies with overweight parents tends to be larger at the time of birth and have a higher risk of developmental problems.
So if you are overweight and trying to get pregnant, reaching and maintaining a healthy weight will help you to both conceive and maintain a healthy pregnancy.
What is a Healthy Weight?
Just weighing yourself is not a good way to work out if you are overweight or not, as it does not take into account your general body build. A Body Mass Index (BMI) calculation is more accurate as it takes into account both your height and weight. The calculation for BMI is tricky, so I recommend using the calculator here: BMI Calculator.
A BMI of 25 or above is classified as overweight, with a BMI of 30 or more being classed as obese. A study in the British Medical Journal found that women with a BMI over 38 were significantly less likely to get pregnant compared to women of a healthy weight.
This same study also showed that body fat distribution was more important than weight or BMI for fertility. Women with a high waist to hip ratio (the typical apple body shape) found it harder to conceive than women with a low waist to hip ratio (the typical pear body shape). However, there’s not much you can do about body fat distribution, other than try to get within the recommended BMI score of 18.5 to 24.9.
What Should I Do If I Am Overweight and Trying to Get Pregnant?
This depends upon whether you are overweight and trying to get pregnant now or are thinking about trying in the future.
Not Trying to Get Pregnant Immediately
If you are not trying for a baby right now, but want to in the near future, now is the perfect time to lose weight. Ideally you want to be in the BMI healthy weight range of 18.5 to 24.9, but how you do this is also important.
- Avoid any crash dieting, as any weight loss that you achieve is likely to be put back on after the diet, and often people will regain more weight than they had before the diet.
- Also don’t take any diet pills, as it is unknown what effects these may have when it comes to trying to conceive at a later date.
- Once you have achieved a healthy weight, maintain it for about a year in order to maximise the health benefits and increase your chance of conceiving.
Already Trying to Get Pregnant
If you are already trying to get pregnant or if slimming down and maintaining a healthy weight for a year is too long for you to wait, there are still positive actions you can take.
- Start a diet that would be healthy for you to continue once you become pregnant.
- Look at focusing on the quality of the food that you eat, whilst trying to slightly reduce the quantity.
- Avoid any diet pills, as it is not known what impact these may have upon your fertility and the health of your developing baby.
- If you are dieting, it is also important that you take pregnancy supplements whilst trying to conceive to ensure that you have sufficient stores of all the important vitamins and minerals.
- Folic Acid is a particularly important supplement if you are overweight and trying to get pregnant as overweight women have a higher risk of their babies having neural tube problems.
- Exercise is also important, but introduce this gradually as excess exercise can also impact upon your fertility.
Will Being Overweight Stop Me from Having Fertility Tests?
Being overweight will not stop your doctor from sending you for fertility tests. After all, it might not be your weight which is stopping you from conceiving. If you would like to know more about what to expect when visiting the doctor, check out the section Your Visit to the Doctor for more information.
Will Being Overweight Stop Me from Having Fertility Treatment?
Government Funded Fertility Treatment
Rules for government healthcare provision (for example the NHS in the UK) will change from country to country. There can even be regional differences within the country. Your doctor will be able to advise you of the local rules when you visit them, though in general, overweight people are less likely to be given government funded treatment than people of a healthy weight.
Privately Funded Fertility Treatment
Being overweight may also affect you if you plan to have fertility treatment privately, as some Fertility Clinics have rules that exclude people who are overweight. This is because overweight people have a lower chance of conceiving and carrying to full term. This can affect the Fertility Clinic’s Success Rate negatively. To learn more about Fertility Clinics success rates and the rules clinics can have, see the section Choosing a Fertility Clinic.