Fast facts

  • Miscarriage is the loss of a pregnancy before it has reached 20 weeks' gestation. Miscarriages often occur within the first 12 weeks of pregnancy.
  • In many cases, your body can identify that there is a problem occurring in the pregnancy; a miscarriage is your body's way of dealing with this problem. About one in every four pregnancies are miscarried. Many miscarriages occur soon after conception and can appear as nothing more than a small change in your period.
  • A miscarriage can be a very stressful experience for you and your partner. Remember that it is natural and not your fault.
  • In many cases, miscarriage carries no risk to a mother's health. However, if an incomplete miscarriage occurs, an infection may also result; this is known as a septic miscarriage. This can involve flu-like aches, fevers and chills, abdominal pain, ongoing bleeding or smelly discharge. Consult your doctor if these symptoms occur.

Fevers

An increase in body temperature above the normal temperature range. Fever is often caused by the body's immune reaction to infection.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

Abdominal

Relating to the abdomen, the middle portion of the trunk which contains organs such as the intestines, stomach and liver.

What is miscarriage?

Miscarriage is defined as the loss of a pregnancy before it has reached 20 weeks' gestation. If a loss of pregnancy occurs after 20 weeks, it is known as a stillbirth. Miscarriages often occur without any obvious cause. A miscarriage can be a very stressful, confusing and sad time, but it is important to remember that miscarriage can happen naturally to anyone and you are not to blame and should not feel guilty. It may be a surprising fact, but about one in four pregnancies are miscarried. [1]  Many of these pregnancies are lost soon after conception and can appear as nothing more than a small change in your monthly period.

1. Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.

Signs and symptoms

Miscarriages often occur within the first 12 weeks of pregnancy. This can lead to the presentation of symptoms including varying severity of vaginal bleeding and spotting, and occasional passing of fluids and tissue from the vagina. Pain and cramping are also commonly felt in the abdomen, uterus or lower back. Various types of miscarriages can occur, each with slightly different symptoms:

  • Complete miscarriage: the body has passed all of the pregnancy tissue spontaneously. Your doctor may make sure that this is a complete miscarriage by examining you to ensure the cervix is closed. An ultrasound can also be performed to look for any remaining pregnancy tissue;
  • Incomplete miscarriage: some of the contents of the uterus are expelled, but some tissue remains behind. Treatment is often required to prevent any complications such as heavy bleeding or infection;
  • Threatened miscarriage: vaginal bleeding occurs in the first half of pregnancy but the outcome is not yet certain. The bleeding may stop and the pregnancy continue to full term, or the bleeding continues and becomes heavier, resulting in a miscarriage. and;
  • Missed miscarriage: the embryonic and placental tissues remain in the uterus, but the embryo has stopped forming or did not form.

Abdomen

The part of the body that lies between the chest and the pelvis.

Cervix

The lower part of the uterus, leading out into the vagina.

Embryo

An organism in the early stages of development. An unborn human between the time of fertilisation and the eighth week of pregnancy.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

Ultrasound

A scan that uses high-frequency soundwaves to produce images of the body’s internal structures.

Uterus

The hollow organ of the female reproductive system that is responsible for the development of the embryo and fetus during pregnancy. Also known as the womb.

Embryonic

Relating to the earliest stage of human development within the uterus, which begins from conception through to the eighth week after conception.

1. Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.

Causes

The specific cause of many miscarriages is often not known. In many cases, your body identifies that there is a problem in the pregnancy; a miscarriage is the body's way of dealing with this problem.

Some causes of miscarriage include:

  • Developmental problems: the process of an embryo developing from a single cell into a baby is hugely complicated and requires many steps to happen in the correct way and in the correct order. Sometimes, natural errors occur in this process result in the pregnancy not being able to continue. One example of this is molar pregnancy, which involves the placenta growing into a mass of cysts;
  • Uterus abnormalities. In some cases the lining of the uterus may not allow the embryo to bind to it and develop, or can reject the developing fetus at a later stage;
  • Ectopic pregnancy: the embryo forms outside the uterus, usually within a fallopian tube, and;
  • Serious infections, which can harm the delicate tissues of a growing fetus.

Cysts

A closed sac in or under the skin that contains fluid.

Embryo

An organism in the early stages of development. An unborn human between the time of fertilisation and the eighth week of pregnancy.

Fallopian tube

The tube-like structures connecting a woman's uterus to her ovaries. Eggs released by the ovaries travel to the uterus via the fallopian tubes.

Fetus

An unborn human, from the ninth week of pregnancy until birth.

Infections

Entry into the body of microorganisms that can reproduce and cause disease.

Placenta

The organ that forms within the uterus of a pregnant woman to provide the fetus with nourishment from the blood supply of the mother.

Uterus

The hollow organ of the female reproductive system that is responsible for the development of the embryo and fetus during pregnancy. Also known as the womb.

1. Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.

Risk factors

Risk factors of miscarriage include:

Amniotic fluid

The fluid surrounding and protecting the fetus inside the uterus during pregnancy.

Prenatal

Before the birth of a baby.

Diabetes

A metabolic disorder that is caused by problems with insulin secretion and regulation and which is characterised by high blood sugar levels. Also known as diabetes mellitus.

Fetus

An unborn human, from the ninth week of pregnancy until birth.

Placenta

The organ that forms within the uterus of a pregnant woman to provide the fetus with nourishment from the blood supply of the mother.

Amniocentesis

A test performed between 16 and 20 weeks into pregnancy to diagnose genetic abnormalities in the unborn baby, such as Down's syndrome. The test involves removing a sample of (amniotic) fluid around the unborn baby for analysis.

Chorionic villus sampling

A test carried out usually between 10 and 12 weeks of pregnancy on a sample of placenta, to diagnose Down's sydnrome or other genetic abnormalities in the unborn baby.

1. Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.

Methods for diagnosis

A miscarriage can sometimes be diagnosed based on signs and symptoms. To help diagnose a miscarriage, your doctor can also perform a variety of tests. These may include:

  • Ultrasound, which produces an image of your body's internal structures and can be used to identify the presence of a fetal heartbeat and check that the embryo is developing correctly, or if a miscarriage has occurred;
  • Blood tests, which can be used to check the levels of specific hormones that change during pregnancy or miscarriage;
  • Tissue tests, which involve the testing of pregnancy tissue that has been passed. Checking this in a laboratory can confirm that a miscarriage has occurred, and;
  • Pelvic examination, which involves your doctor checking if your cervix has begun to dilate, indicating a miscarriage.

Cervix

The lower part of the uterus, leading out into the vagina.

Embryo

An organism in the early stages of development. An unborn human between the time of fertilisation and the eighth week of pregnancy.

Pelvic examination

An examination performed by your doctor or nurse that involves a speculum examination with a duck-bill instrument and an internal examination in which they may put two gloved fingers inside your vagina to check for lumps or tender regions.

Ultrasound

A scan that uses high-frequency soundwaves to produce images of the body’s internal structures.

1. Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.

Types of treatment

Unfortunately, it is not possible to stop a miscarriage once it has started. However, there are several management options available, depending on the stage of the miscarriage and the woman's condition. These can include:

Observation

For some women, little treatment is required after a miscarriage, particularly for those who have a complete miscarriage. If there is no sign of infection and vital signs including blood pressure and pulse are stable, then management without medical or surgical treatment is possible. If a miscarriage was not complete, over time (usually within two weeks), the contents of the uterus will pass and an ultrasound can be performed to check for the completion of the miscarriage.

Medication

In some cases of miscarriage, it is possible to stimulate the pregnancy tissue to pass from the uterus using medications. Medications will work over a period of days and can be given either orally or vaginally.

Surgical treatment

A usual treatment for an early miscarriage involves surgical cleaning of your uterus, particularly if your miscarriage involves continuous bleeding. This process is called dilation and curettage (D&C), and involves suction and/or gentle scraping to remove any remaining pregnancy tissue.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

Ultrasound

A scan that uses high-frequency soundwaves to produce images of the body’s internal structures.

Uterus

The hollow organ of the female reproductive system that is responsible for the development of the embryo and fetus during pregnancy. Also known as the womb.

1. Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.

Potential complications

In many cases, miscarriage carries no risk to a mother's health. However, if an incomplete miscarriage occurs, an infection may also result; this is known as a septic miscarriage. This can involve flu-like aches, fevers and chills, abdominal pain and ongoing bleeding or smelly discharge. It is important to consult your doctor if these symptoms occur.

If the miscarriage is due to an ectopic pregnancy, in which the embryo develops outside the uterus, there is a risk of damage to the fallopian tubes as well as the potential for internal bleeding.

Rhesus disease

A blood test is commonly performed to check the blood group, particularly the Rhesus factor status, of the mother. The Rhesus factor is a protein that can be found on red blood cells. Most people have this protein (Rhesus-positive); however, some people may not have this protein (Rhesus-negative).

If the mother is Rhesus-negative, she would normally be given anti-D immunoglobulin, after the miscarriage, to prevent the formation of antibodies that can complicate further pregnancies. The formation of antibodies to the Rhesus protein can lead to a condition known as Rhesus disease or haemolytic disease of the newborn. Rhesus disease occurs when a Rhesus-negative mother initially has a Rhesus-positive baby, which may lead to the formation of antibodies to the Rhesus protein. If in subsequent pregnancies, she has a Rhesus-positive baby, the previously formed antibodies can cause destruction of red blood cells in the unborn baby, leading to swelling, jaundice and even death of the baby.

Antibodies

A protein molecule produced by the immune system. Antibodies bind specifically to foreign substances to neutralise them or target them for destruction.

Embryo

An organism in the early stages of development. An unborn human between the time of fertilisation and the eighth week of pregnancy.

Fallopian tubes

The tube-like structures connecting a woman's uterus to her ovaries. Eggs released by the ovaries travel to the uterus via the fallopian tubes.

Fevers

An increase in body temperature above the normal temperature range. Fever is often caused by the body's immune reaction to infection.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

Jaundice

A yellowing of the skin, the whites of the eyes and the mucous membranes, due to an accumulation of bilirubin in the blood. Often a symptom of liver problems.

Rhesus factor

A protein that may be present on the surface of a red blood cell. The presence of this protein makes someone a positive blood group, whereas the absence means they are a negative blood group.

Uterus

The hollow organ of the female reproductive system that is responsible for the development of the embryo and fetus during pregnancy. Also known as the womb.

Abdominal

Relating to the abdomen, the middle portion of the trunk which contains organs such as the intestines, stomach and liver.

Anti-D immunoglobulin

A medicine given to pregnant women with Rhesus-negative blood to stop them producing antibodies against their unborn baby's blood that is Rhesus-positive.

1. Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.

Prognosis

The occurrence of a miscarriage can be a very stressful experience for you and your partner as you deal with your loss. However, it is important to remember that it is natural and not your fault. If you believe you have had a miscarriage, it is best to consult your doctor. Sometimes, you can have mixed feelings about whether to become pregnant again. The good news is that, after a single miscarriage, it is possible for most women to become pregnant again and reach a full-term pregnancy. It is possible to try to become pregnant quite soon after a miscarriage, but it is best to wait until you have experienced at least one normal period. It can help to talk to a trusted friend or counsellor about your miscarriage.

Counselling sessions are a helpful way of dealing with a miscarriage.Counselling can be helpful in dealing with a miscarriage. 

1. Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.

Prevention

There is no way to stop a miscarriage once it has begun. However, it is possible to reduce the chances of miscarriage occurring by limiting your risks. This can include being as healthy as possible by eating a balanced diet with lots of fruit and vegetables. It is important to maintain a healthy weight, quit smoking, understand food safety in pregnancy and avoid the use of alcohol and illicit drugs.

1. Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.