Sunday, April 27, 2008
Miscarriage Factsheet
This factsheet is for people who have had a miscarriage or for those who want to know more about them.
What is it?
The medical definition of miscarriage is the spontaneous loss of a pregnancy before 24 weeks. Miscarriage is very common, occurring in 10 to 20 percent of confirmed pregnancies. Most of these occur in the first 12 weeks of pregnancy.
Miscarriage symptoms
Why does it happen?
About half of all early miscarriages happen because of a problem in the way genetic material from the egg and sperm has combined during fertilisation. It can be difficult to find out why this has happened but it is more likely to be due to random chance than to any underlying problem with either parent.
Imbalances in pregnancy hormones, problems in the immune system, and some serious infections (not minor coughs or colds) are also thought to make miscarriages more likely. The risk of miscarriage increases with age, because the quality of eggs deteriorate. If a woman drinks too much alcohol or smokes heavily, the risk of a miscarriage is higher. It is also increased with multiple pregnancies, such as twins.
If a woman has previously taken the contraceptive pill, the risk of having a miscarriage appears to be slightly reduced.
While some studies suggest that stress may play a role in pregnancy loss, it hasn't been shown to cause miscarriages on its own. Research also indicates that doing moderate exercise or having sex whilst pregnant does not increase the risk of miscarriage.
Often the cause of a miscarriage remains unknown. If a miscarriage has started there is very little that can be done to stop it.
What should I do if I notice bleeding in pregnancy?
If you experience vaginal bleeding at any time during pregnancy it is worth contacting your doctor or midwife for advice.
You may be referred to an early pregnancy assessment unit, which is often based at a local hospital, and may be given an ultrasound scan.
At hospital
After a discussion of the symptoms, and possibly an examination, some tests and investigations may be needed to find out what is happening. Some examples are listed below.
- An ultrasound scan will show the uterus and any developing embryo. If all is well and the pregnancy is sufficiently advanced, a fetal heartbeat can be seen. If pregnancy is not very far on (less than six to seven weeks) it is sometimes not possible to tell if the pregnancy is continuing, and you may be recommended to have another scan in 7 to 10 days time.
- Sometimes a blood test for beta hCG is taken. This is a sensitive blood test which identifies levels of the pregnancy hormone. You may be asked to return after 48 hours to re-take the test. In pregnancy, levels of the hormone rise over time. If they are decreasing, it indicates that the pregnancy has been lost.
- You may be given a blood test to find out if you have a rhesus-negative blood group. If you do, you may need an injection to prevent problems in subsequent pregnancies.
Types of miscarriage
Different terms are used to describe miscarriage, depending on what the ultrasound scan or an internal examination reveals.
Threatened miscarriage is used to describe bleeding in early pregnancy, where the cervix is found to be tightly closed. The pregnancy is most likely to continue. Some doctors may advise you to rest in bed, although there is little evidence to suggest that this will make any difference to what happens.
Inevitable miscarriage describes bleeding in early pregnancy where the cervix is found to be open, suggesting that the pregnancy will be lost.
Incomplete miscarriage describes a miscarriage that has definitely started, but there is still some pregnancy tissue left in the uterus. The cervix is usually found to be open.
Missed miscarriage describes a pregnancy that stopped growing some weeks ago, but there was no bleeding at that time. This type of miscarriage usually causes a small amount of dark-brown blood loss and the sudden end of normal pregnancy symptoms but there may be no symptoms at all, coming to light only at a routine scan. It is sometimes called a blighted ovum.
Treatment options
Doctors can prescribe a combination of misoprostol and mifepristone. These soften the cervix and make the uterus contract so that the remainder of the pregnancy is expelled.
Surgical treatment involves an operation to empty the uterus. This is known as an evacuation of retained products of conception (ERPC), but is sometimes called a dilatation and curettage (D&C). This is carried out under general anaesthesia. A soft plastic tube is passed through the cervix into the uterus and the pregnancy material is removed by suction.
General anaesthesia can temporarily affect your co-ordination and reasoning skills, so you should not drive, drink alcohol, operate machinery or sign legal documents for 48 hours afterwards. If you are in any doubt about driving, please contact your motor insurer so that you are aware of their recommendation, and always follow your doctor's advice.
Recurrent miscarriage
Miscarriage is a very common event and many women experience two or more miscarriages, purely by chance. Having more than one miscarriage can lead to anxieties that a normal pregnancy will never occur. But even after two miscarriages it is unlikely that you have an underlying problem, and there should be every chance of a successful pregnancy in the future.
After three consecutive miscarriages it is advisable to undergo some tests to rule out a specific cause. Possibilities include a hormonal disturbance, genetic problems, abnormalities of the uterus, or a condition of the immune system called "antiphospholipid syndrome". This is a disease where the body's own defence mechanism causes blood clots in the placenta.
Miscarriage later in pregnancy
Four-fifths of miscarriages occur in the first 12 weeks (first trimester) of pregnancy. Pregnancy loss later than this is much less common, and the causes may be different to those described above. You may need more specialist information and advice.
After a miscarriage
Further information
- The Miscarriage Association
01924 200 799
www.miscarriageassociation.org.uk