In many cases, the cause of a miscarriage isn't known and you wouldn't have been able to prevent it.

However, there are ways to lower your risk of miscarriage, including:

• not smoking during pregnancy
• not drinking alcohol or using illegal drugs during pregnancy
• eating a healthy, balanced diet with at least five portions of fruit and vegetables a day
• making attempts to avoid certain infections during pregnancy, such as rubella
• avoiding certain foods during pregnancy, which could make you ill or harm your baby
• being a healthy weight before getting pregnant

Your weight

Obesity increases your risk of miscarriage. A person is obese when they have a body mass index (BMI) of over 30. You can check your BMI using the healthy weight calculator. If you're pregnant, your midwife or doctor may be able to tell you your BMI.

The best way to protect your health and your baby's wellbeing is to lose weight before you become pregnant. By reaching a healthy weight, you cut your risk of all the problems associated with obesity in pregnancy. Contact your GP for advice about how to lose weight. They may be able to refer you to a specialist weight-loss clinic.

As yet, there's no evidence to suggest losing weight during pregnancy lowers your risk of miscarriage, but eating healthily and activities such as walking and swimming are good for all pregnant women.

If you weren't active before becoming pregnant, you should consult your midwife or doctor before starting a new exercise regimen while you're pregnant.

Read more about obesity and pregnancy and exercise in pregnancy.

Treating an identified cause

Sometimes the cause of a miscarriage can be identified. In these cases, it may be possible to have treatment to prevent this causing any more miscarriages. Some treatable causes of miscarriage are outlined below.

Antiphospholipid syndrome

Antiphospholipid syndrome (APS), also known as Hughes syndrome, is a condition that causes blood clots. It can be treated with medication. Research has shown that a combination of aspirin and heparin (a medicine used to prevent blood clots) can improve pregnancy outcomes in women with the condition.

Read more about treating antiphospholipid syndrome.

Weakened cervix

A weakened cervix, also known as cervical incompetence, can be treated with an operation to put a small stitch of strong thread around your cervix to keep it closed. This is usually carried out after the first 12 weeks of your pregnancy, and is removed around week 37.