Weight gain in pregnancy

Tell your midwife or maternity service if you have concerns about your weight gain during your pregnancy

Weight gain during pregnancy varies. Most times the weight gain can be because of the growing baby. You can expect to put on some weight as long as your pregnancy is progressing normally.


Contact information for your local maternity service

East and North Hertfordshire (The Lister Hospital): 01438 284 124

West Essex (The Princess Alexandra Hospital): 01279 827 286 

South and West Hertfordshire (Watford General Hospital): 01923 217 343

Weight gain in pregnancy

Weight gain in pregnancy varies greatly. Most pregnant women gain between 10kg and 12.5kg (22lb to 26lb), putting on most of the weight after week 20. Much of the extra weight is due to your baby growing, but your body will also be storing fat, ready to make breast milk after your baby is born. If you are overweight or obese there is no UK based evidence on how much weight you should gain during pregnancy. American research has suggested that limiting your weight gain to below 10kg may be beneficial to mum and baby.

Gaining too much or too little weight

Putting on too much weight can affect your health and increase your blood pressure. It is not recommended to go on a restricted diet, however eating healthily and staying active is beneficial for your baby.

Gaining too much weight can increase your risk of complications. These include:

  • gestational diabetes: too much glucose (sugar) in your blood during pregnancy can cause gestational diabetes, which increases your risk of having a large baby
  • pre-eclampsia: a rise in blood pressure can be the first sign of pre-eclampsia; although most cases are mild and cause no trouble, pre-eclampsia can be serious

If you are concerned that you are not gaining weight with you pregnancy or losing weight, you can find help and information from Tommy. org or your midwife. 

Staying active

Staying active is important while you’re pregnant, as it will prepare your body for labour and birth.

By exercising during pregnancy you are less likely to develop gestational diabetes, pre-eclampsia or have excessive weight gain. Exercise during pregnancy is also very good for your mood stability.  

Keep up your normal daily activity or exercise (unless you’ve been advised by your midwife or GP not to exercise). Please see our page on exercise during pregnancy for more information.


Find out more on weight gain during pregnancy

NHS UKWeight gain in pregnancy - NHS (www.nhs.uk)

RCOGBeing overweight in pregnancy and after birth | RCOG

Squeezy AppAbout Squeezy For Women - Squeezy (squeezyapp.com)

There are free weight management services during pregnancy. Please ask your midwife to refer you.

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