- 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
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.
Overweight
Being overweight or obese during pregnancy can put you at an increased risk of complications. If you are overweight, the best way to protect your health and your baby's well being is to lose weight before you become pregnant. By reaching a healthy weight, you increase your chances of conceiving naturally and reduce your risk of the problems associated with being overweight in pregnancy.

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).
It is important to have a healthy balanced diet and moderate exercise throughout pregnancy. This will help you maintain your weight rather gaining too much. Please read the information in the staying healthy in pregnancy and weight gain section.
Many areas offer free weight management support services before, during and after pregnancy. Please ask your midwife for details in your local area.
Many units offer free weight management services during pregnancy. Please ask your community midwife to refer you.