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Planning a pregnancy

The best way to protect your health and your baby's wellbeing is to maintain a healthy weight before you become pregnant.  If you're overweight you may have problems getting pregnant, and if you're having fertility treatment it's less likely to work. Before you get pregnant you can use the BMI healthy weight calculator to work out your BMI. However, this may not be accurate once you are pregnant, so consult your midwife or doctor.

During pregnancy

Although many women who are overweight or obese have a successful pregnancy and a healthy baby, being overweight or obese (having a BMI over 30) significantly increases the risk of the following problems during pregnancy, or problems for your baby in the short or long-term:

  • miscarriage
  • gestational (or pregnancy related) diabetes
  • high blood pressure and pre-eclampsia
  • blood clots
  • infection (urine and post-caesarean wound infections)
  • haemorrhage after the birth
  • problems with breastfeeding
  • having a baby with an abnormally high birthweight

You are also more likely to need:

  • induction and instrumental (ventouse or forceps) delivery
  • caesarian section

Problems for your baby can include:

  • stillbirth
  • birth defects (congenital abnormality)
  • a higher chance of health problems later in life, including obesity and diabetes

By attending all of your ante-natal appointments, your midwife or other health professionals involved can keep an eye on both you and your baby and manage any issue that may arise.

Tips for a healthy weight

Having a healthy diet and getting moderate exercise are advised in pregnancy, and it's important not to gain too much weight, although it is not safe to try to lose weight once you become pregnant.  You may feel that you need to eat more although 'eating for two' is a common myth and it's about getting the right balance of foods rather than larger amounts.  You can keep to a healthy weight by eating a balanced diet and getting daily exercise.

If you are concerned about your weight and you are planning to become pregnant or are already pregnant speak to your GP or midwife. 

NHS Choices has further information about all of the topics discussed above and more.


Fact Zone

Feeding at night helps to stimulate your milk supply.