Miscarriage: overview

by | Babies and Pregnancy

A miscarriage is the spontaneous loss of a pregnancy before 20 weeks. After 20 weeks of pregnancy, the loss of a fetus is called a stillbirth.

Miscarriage is very common. In fact, it has been estimated that up to half of all pregnancies end in an early miscarriage that occurs before the first period would have been missed, when most women do not yet know they are pregnant. Of pregnancies that make it past this point, about 10 to 20 per cent result in a miscarriage, mostly during the first 12 weeks.

Sometimes your doctor or nurses may refer to your miscarriage as a spontaneous abortion. Abortion is the common medical name for all pregnancies that end before 20 weeks — both miscarriages and terminations.

Why does miscarriage occur?

Usually it is difficult to determine exactly why a miscarriage has occurred. In almost all cases it is not anything that the mother has done or could have prevented. Most women go on to have a healthy pregnancy after a miscarriage.

Most miscarriages occur because something went wrong during or soon after conception. Some of the causes of miscarriage include the following.

  • In many cases the part of the pregnancy that grows into the baby fails to develop properly. This may be due to genetic abnormalities in the baby’s cells. These are usually genetic problems that have occurred by chance, rather that inherited problems from the parents.
  • Sometimes a fertilised egg implants in the uterus but an embryo does not develop – this is called a blighted ovum.
  • The fertilised egg may not attach itself to the wall of the uterus or attaches in the wrong place. A pregnancy that develops outside the uterus (often in a fallopian tube) is called an ectopic pregnancy.
  • The mother’s body may not make enough of the hormones that support a pregnancy, such as progesterone.
  • Something may be wrong with the placenta.
  • The mother’s immune system may affect the placenta and stop it from developing normally.
  • The mother may have an underlying medical condition, such as uncontrolled diabetes, a thyroid problem, or a tendency towards blood clots.
  • She may have a problem with her uterus (such as fibroids or an abnormally shaped uterus) or a weak cervix.

Risk factors for miscarriage

There are factors that can increase the risk of miscarriage, such as:

  • Exposure to some environmental chemical pollutants, including cigarette smoke.
  • Drinking more than 3 alcoholic drinks per week in the first trimester (first 12 weeks of pregnancy) may increase the risk of miscarriage.
  • Some studies suggest that a high intake of caffeine (more than 3 to 5 cups of coffee per day) may increase the risk of miscarriage.
  • Age. The risk of miscarriage rises after the age of 35, and rises further from the age of 40 years.
  • Some tests that may be offered to women in early pregnancy, such as amniocentesis or chorionic villous sampling (CVS), are associated with a small risk of miscarriage.

Symptoms of miscarriage

Symptoms may differ depending on how advanced the pregnancy was and what caused the miscarriage. Early symptoms may include:

  • vaginal bleeding or spotting; or
  • vaginal discharge;
  • pain similar to period pain (uterine cramps); or
  • no longer ‘feeling’ pregnant, for example, the tender breasts and nausea associated with pregnancy may disappear.

If you have any of these symptoms, talk to your doctor or contact your local Early Pregnancy Assessment Service.

In many cases, the symptoms may be due to a threatened miscarriage. This is where there is bleeding but the cervix has not dilated, and the symptoms settle down and the pregnancy continues as normal. Also, spotting is very common in early pregnancy, and most women with this symptom alone are not having a miscarriage.

When a miscarriage happens, the cervix opens and part or all of the contents of the uterus come away and pass out of the vagina. There are several common signs of miscarriage.

  • Bleeding becomes heavy.
  • Pain is like bad period pain or birth contractions.
  • Faintness and nausea.
  • You pass pieces of placenta which look like blood clots.
  • You may see a recognisable embryo or fetus.

An incomplete miscarriage occurs when some pregnancy tissue remains inside the uterus.

What should I do if I think I am miscarrying?

  • Ring your doctor or local hospital and describe your symptoms. Ask your partner, a friend or relative to stay with you, preferably someone who can take you to the doctor or hospital if necessary.
  • Keep a record of how many pads you go through and how heavily stained they are.
  • Save any pregnancy tissue that you pass, as your doctor may recommend it is tested to see why your miscarriage happened.
  • If you are alone and things are happening fast, dial 000 and ask for an ambulance.


Your doctor will ask about your symptoms and how long they have been happening. Your doctor may also perform a physical examination, including an internal examination to see if your cervix is dilated.


Tests may include the following.

  • An ultrasound examination can be done to check for a fetal heartbeat. If a miscarriage has occurred, ultrasound can show whether some or all of the pregnancy tissue remains in the uterus (incomplete or missed miscarriage) or whether no pregnancy tissue remains in the uterus (complete miscarriage). An ultrasound can also diagnose a blighted ovum or an ectopic pregnancy (a potentially serious condition where a pregnancy implants outside the uterus, usually in a fallopian tube).
  • Blood tests may be recommended to measure the amount of pregnancy hormone (beta-HCG) and whether it is decreasing.
  • Testing of any pregnancy tissue that you have passed may be recommended. Unfortunately, testing after a miscarriage does not often reveal the cause of the miscarriage.

If you have had more than one miscarriage in a row, your doctor may recommend further testing. Testing is usually recommended after 3 consecutive miscarriages. Consecutive miscarriages affect less than 5 per cent of women.


Unfortunately, once a miscarriage has begun there is no treatment that can stop it happening. Treatment is aimed at reducing the risk of infection, treating heavy bleeding and pain, and ensuring that you are given adequate support and information.

Expectant management for miscarriage

Expectant management involves confirming that a miscarriage has occurred, and then allowing the miscarriage to occur naturally. This may take a couple of days, or sometimes up to 4 weeks.

Expectant management is usually recommended for early miscarriages – those that happen up to about 8 weeks, and incomplete miscarriages, when there is only a small amount of pregnancy tissue remaining. Many women choose this option, and it is generally safe when done in consultation with your doctor.

Pain relievers can be used to treat cramping abdominal pain, which usually occurs when the pregnancy tissue is passing.

Some women treated with expectant management will need to go on to have medical or surgical treatment if the tissue does not pass on its own, if bleeding becomes too heavy, or if an infection develops.

Medical treatment for miscarriage

Medicines can be used to help the pregnancy tissue pass. These medicines can be used for incomplete or missed miscarriages. For an incomplete miscarriage, the pregnancy tissue usually passes within a couple of days (often just a couple of hours), while missed miscarriages may take longer – up to 2 weeks.

Medical management is normally not recommended after 9 weeks or if there is heavy bleeding or signs of infection.

The medicine can be taken orally or it can be inserted into the vagina. When taken vaginally, the medicine may work better and there may be fewer side effects.

Side effects can include: nausea, vomiting and diarrhoea.

Surgical treatment of miscarriage

You may need to have a dilatation and curettage (D & C) if you have heavy or persistent bleeding, pain or if there is a large amount of tissue left behind in the uterus. Some women also choose this option.

The tissue needs to be removed due to the risk of infection developing from tissue remaining in your uterus. Dilation and curettage is generally recommended for pregnancies after 10-12 weeks.

For this procedure, you will usually be given a general anaesthetic, your cervix is gently dilated (opened) and the remaining pregnancy tissue is removed from your uterus.


  • Simple pain relievers (such as paracetamol) can be used for crampy abdominal pain.
  • Use pads, rather than tampons, to reduce the risk of infection. It is okay to have sex once the bleeding has settled if you feel comfortable.
  • Remember to use contraception if you don’t want to get pregnant again.
  • If you are planning another pregnancy, it is often recommended to wait until after you have had one normal period before trying to get pregnant again, as studies suggest there is a slightly higher risk of miscarriage in women who get pregnant straight away.

After a miscarriage

After a miscarriage, it is normal to feel physically and emotionally drained. Rest is essential after having a miscarriage. If possible take a few days off work or have someone look after your home and children.

Bleeding from the vagina may continue for 7 to 21 days, gradually becoming lighter until it stops. To reduce the risk of infection, it is important to avoid having sex until the bleeding has finished. You should also use sanitary pads rather than tampons.

If your pregnancy lasted close to 20 weeks, your breasts may produce milk within a few days. Some women find the milk production upsetting and a reminder of their loss; others find it a comforting link with their lost baby that helps them to grieve. Your doctor or midwife should be able to advise you on suppressing and stopping your milk supply.

As you can conceive soon after a miscarriage, it may be advisable to start using contraception immediately. Make sure that both you and your partner are physically and emotionally ready before trying for another pregnancy.

When should I contact my doctor?

  • If bleeding continues longer than a week or is heavy.
  • If you notice a bad-smelling vaginal discharge.
  • If you have any abdominal pain.
  • If you have a fever.

How will I feel?

Everybody reacts differently and you should accept your feelings, whatever they are. There is no ‘correct’ way to feel after a miscarriage. Many people feel shocked and numb for a while. Once this passes, it is common to be upset. It is also common to feel angry about the miscarriage.

Many people, especially those who did not plan their pregnancy, are surprised at just how strong their feelings are. They may find themselves unexpectedly crying, or that they keep thinking about the miscarriage. Some people experience feelings of guilt or failure. Those who have not experienced miscarriage may find it difficult to understand why you are so upset. On the other hand, not everyone will feel the same – you shouldn’t feel obligated to experience grief.

All of the above feelings are common. Don’t try to ignore your feelings, as they can take much longer to resolve if you try to stop the grieving process. Men often find it hard to express their feelings and may need encouragement to show their grief.

Your partner may respond in a different way to you. Communication difficulties among partners are common after miscarriage and it may be difficult to connect with your partner while you are feeling grief and sadness. It may help to be open and honest with your partner and to try and look after your relationship as well as each other.

Bereaved people find different ways to help them through their grief. There is no right way to do it. Mostly these strong feelings will subside with time, open communication, and support from friends or family. Occasionally they can be a trigger for a prolonged episode of low mood or even depression. Seek advice from your doctor or other health professionals if you need help managing your grief.

Support after miscarriage

Support is available following miscarriage. Talk to your doctor or Early Pregnancy Assessment Service. There are also support organisations in Australia who focus on miscarriage, such as:

  • Sands (a miscarriage, stillbirth and neonatal death charity), who have a National Support Line: 1300 072 637. www.sands.org.au
  • Pink Elephant (a support network for those experiencing miscarriage and early pregnancy loss): www.miscarriagesupport.org.au