A molar pregnancy occurs when the pregnancy develops abnormally, forming a mass of tissue inside the uterus. It is sometimes also known as a hydatidiform mole. There is usually a period of monitoring hormone levels following a molar pregnancy.…
- 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.
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.  Many of these pregnancies are lost soon after conception and can appear as nothing more than a small change in your monthly period.
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.
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.
Risk factors of miscarriage include:
- Age - the chances of miscarriage grows as you grow older;
- Smoking, alcohol and illicit drug use;
- Weight - being obese or underweight;
- Invasive prenatal pregnancy diagnostic tests, including amniocentesis and chorionic villus sampling, which involve sampling the amniotic fluid/placenta that surrounds the fetus during pregnancy, and;
- Medical conditions, such as uncontrolled diabetes.
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.
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:
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.
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.
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.
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.
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 hemolytic 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.
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.
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.
- Murtagh J. MD. (2012) John Murtagh’s Patient Education (6th revised edition). North Ryde N.S.W.: McGraw-Hill Australia Pty Ltd.
- Blighted Ovum: What Causes It? - Mayo Clinic. Accessed August 29 2014. http://www.mayoclinic.org/diseases-conditions/pregnancy-loss-miscarriage/expert-answers/blighted-ovum/faq-20057783.
- Miscarriage. Accessed August 29 2014. http://www.uptodate.com/contents/miscarriage-beyond-the-basics?source=search_result&search=miscarriage&selectedTitle=1%7E32.
- Miscarriage | Better Health Channel. Accessed August 29 2014. http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Miscarriage_explained.
- Miscarriage | The Royal Womens Hospital. Accessed August 29 2014. https://www.thewomens.org.au/health-information/pregnancy-and-birth/pregnancy-problems/early-pregnancy-problems/miscarriage/.
- Miscarriage Causes - Diseases and Conditions - Mayo Clinic. Accessed August 29 2014. http://www.mayoclinic.org/diseases-conditions/pregnancy-loss-miscarriage/basics/causes/con-20033827.
- Treating Miscarriage | The Royal Womens Hospital. Accessed August 29 2014. https://www.thewomens.org.au/health-information/pregnancy-and-birth/pregnancy-problems/early-pregnancy-problems/treating-miscarriage/
FAQ Frequently asked questions
What are the symptoms of miscarriage?
Miscarriages often occur within the first 12 weeks of pregnancy. Various types of miscarriages can occur, each with slightly different symptoms. Signs of a miscarriage include: vaginal bleeding and spotting; occasional passing of fluids and tissue from …
What causes miscarriage?
The specific cause of many miscarriage often cannot be found. The process required for the development of an embryo is very complicated and involves countless steps. In many cases, your body identifies a problem with the pregnancy, and the miscarriage is your …
Can anyone have miscarriage?
Even the healthiest woman can have a miscarriage. There are, however, a number of risk factors for miscarriage, including: 1) Age - older women are more likely to have a miscarriage. 2) Smoking, alcohol and illicit drug use. 3) Weight - being obese or …
How is miscarriage diagnosed?
A miscarriage can sometimes be diagnosed based on signs and symptoms. To help diagnose a miscarriage, your doctor can also perform tests. These may include: ultrasound, which produces an image of your body's internal structures and can be used to identify the …
How is miscarriage treated?
Unfortunately, it is not possible to stop a miscarriage once it has started. There are several management options available, depending on the stage of the miscarriage and the woman's condition. The options include observing the process of miscarriage to ensure a …
What are the complications of miscarriage?
In many cases, miscarriage poses 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 …
How common is miscarriage?
It may be a surprising fact, but about one in four pregnancies are miscarried or 'lost'. Many of these pregnancies are lost soon after conception and can appear as nothing more than a small change in your period.