It is hard to know how many miscarriages take place because sometimes a miscarriage can happen before the mother realises she is pregnant. The estimated figure is that miscarriage happens in around 1 in 4 recognised pregnancies, with 85% of those happening in the first trimester (weeks 1 to 12).
A 'late' miscarriage, which is much less common, may occur between weeks 13 to 24 of pregnancy. After 24 weeks, the delivery of a baby who has died in the womb is referred to as a stillbirth.
Age makes a difference to risk levels:
- If a woman is under 30, she has a 1 in 10 chance of miscarriage
- If a woman is between 35 and 39, she has a 2 in 10 chance of miscarriage
- If a woman is over 45, she has a 5 in 10 chance of miscarriage.
What are the signs of miscarriage?
The main sign of a miscarriage is vaginal bleeding. This may be followed by cramping and pain in the lower abdomen.
Vaginal bleeding is the most common symptom of a miscarriage; it can vary from light spotting to a heavy bleed, heavier than a normal period. Some women are shocked by the volume of blood that they seem to lose.
Other signs are cramping or abdominal pain. Some women describe simply not feeling pregnant anymore. They may have lost the pregnancy symptoms such as nausea or breast tenderness that they had previously been feeling.
We still don’t know why all early miscarriages occur. In some cases, however, it is due to a genetic or chromosomal problem in the developing baby.
Can anything be done to avoid miscarriage?
There are some things you can do to bring down your risk of having a miscarriage.
Quit smoking (if you smoked) and avoid secondhand smoke
Avoid drinking alcohol in pregnancy
Don't use street drugs while pregnant
Stick to the recommended limit for caffeine.
Chromosomes contain the genetic material important for the make-up of the baby, and are found inside every cell within the body. When something goes wrong during the passing on or division of chromosomes, it can cause genetic abnormalities in the baby. If these are incompatible with life, a miscarriage will usually occur. Chromosomal abnormalities are more likely in the babies of older mothers.
A chromosomal abnormality resulting in a miscarriage won’t affect subsequent pregnancies.
Find out more about the why miscarriage happens.
Am I at risk?
The following people have a slightly higher risk of having an early miscarriage
- Older women: at 30, a woman has a 20% chance of miscarriage; at 42, this increases to 50%.
- People with underlying health problems, such as poorly controlled diabetes
- People who engage in lifestyle choices that are harmful to the developing baby, such as heavy drinking, smoking and taking recreational drugs
- People who are obese have an increased risk of miscarriage.
An ectopic pregnancy is a pregnancy that develops in the fallopian tubes instead of in the womb. Sometimes an ectopic pregnancy can also develop in the abdominal cavity. An ectopic pregnancy will end in miscarriage.
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7. NHS Choices [accessed 1 October 2015] Miscarriage, causes. http://www.nhs.uk/Conditions/Miscarriage/Pages/Causes.aspxHide details
ℹLast reviewed on April 1st, 2015. Next review date April 1st, 2018.