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.

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 stating 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

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).

Many units offer free weight management services during pregnancy. Please ask your community midwife to refer you.

Improving the physical and emotional health and wellbeing of expectant mothers, infants, children and young people throughout Aneurin Bevan University Health Board Area.

(N.B: The Family and Therapies team at ABUHB is NOT responsible for the content on the webpage links that we refer to in our resource sections and linked information to external sites. All information was accurate and appropriate at the time the webpage was created.)

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