why did I miscarry?

Even though about one in four pregnancies ends in miscarriage, it is usually difficult to know the exact cause and most women never find out the cause of their loss, even if they have investigations. It can be hard to accept that no-one can say for certain why it happened. That doesn’t mean that it is your fault – your miscarriage is unlikely to have happened because of anything you did or didn’t do.

The main causes of miscarriage are thought to be:

Genetic: In about half of all early miscarriages, the baby does not develop normally right from the start and cannot survive.

Hormonal: Women with very irregular periods may find it harder to conceive and when they do, are more likely to miscarry.

Immunological: Problems within the blood vessels which supply the placenta can lead to miscarriage.

Infection: Minor infections like coughs and colds are not harmful, but a very high temperature and some illnesses or infections, such as German measles, may cause miscarriage.

Anatomical: If the cervix (neck of the womb) is weak, it may start to open as the uterus (womb) becomes heavier in later pregnancy and this may lead to miscarriage. An irregular-shaped uterus can mean that there is not enough room for the baby to grow. Large fibroids may cause miscarriage in later pregnancy.

Read our leaflet "Why did it happen to us?"