Miscarriages: Risk Factors

Miscarriages can be a difficult and emotional experience for women and their families. Thus, a safe space to process and discuss one’s thoughts and questions is important. We provide an informational guide on miscarriage, discussing causes, risk factors, and coping strategies.

A miscarriage typically happens early in a pregnancy, during the first trimester. It is the unintentional loss of a baby before the 20th week of pregnancy (losses after the 20th week are referred to as stillbirths).

Miscarriage vs. Abortion

Abortion is a term for willingly terminating a pregnancy with medical interventions such as medications or surgical procedures. Miscarriage, on the other hand, is natural or spontaneous without any medical interventions.

Types of miscarriage

Here are a few types of miscarriages that a pregnant woman may experience:

1. When a threatened miscarriage occurs, there are signs of a miscarriage, light vaginal bleeding, lower abdominal pain, but baby’s heartbeat is still present, and the cervix is not dilated.  There may still be a possibility for the pregnancy to continue.
2. When an inevitable miscarriage occurs, vaginal bleeding is heavier and stronger cramps are present along with the cervix being dilated. The chance of a miscarriage occurring is high. This can happen after a threatened miscarriage, or without warning.
3. A complete miscarriage usually happens before the 12th week of pregnancy. All pregnancy tissues (the baby and placenta) are expelled from the uterus. Vaginal bleeding may last for a few days and strong cramps much like labour pain is present.
4. When an incomplete miscarriage occurs, pregnancy tissues are only partially expelled while some remain inside the uterus. Vaginal bleeding and lower abdominal cramping may continue.
5. A missed miscarriage occurs when the foetus dies without the mother knowing it and the tissues are still inside the uterus. Signs may include brownish discharge and pregnancy symptoms such as nausea and tiredness may have subsided.
6. A recurrent miscarriage occurs when a woman experiences repeated miscarriages. If a third or more miscarriage has occurred in a row, consulting a doctor is important to find out the causes.

Causes and risk factors of a miscarriage

In most cases, miscarriages happen beyond the control of a woman. The foetus just ceases to develop, and it does not indicate negligence by the expectant mother. Studies have shown that about 50% of first-trimester miscarriages that have no underlying medical reasons are usually caused by chromosomal abnormalities.

However, there are certain risk factors that can increase your chance of having a miscarriage.

1. Age
   • Women who are older are more likely to have a miscarriage.
   • The risk increases after the age of 30 and is even higher between 35 and 40 years old.
   • In women aged more than 45, 5 out of 10 pregnancies may end in a miscarriage.
2. Previous history of miscarriage 
   • Women who have had a previous miscarriage(s) have an increased risk of having another.
3. Chronic medical conditions
   • Certain medical conditions such as thyroid disorders, polycystic ovary syndrome (PCOS), and uncontrolled diabetes can increase the risk of miscarriage.
4. Smoking, alcohol, or drug abuse
   • Unhealthy lifestyle choices such as smoking, heavy alcohol intake, and drug abuse can increase your risk of a miscarriage.
5. Uterine or cervical problems
   • The cervix (uterine neck) muscles can be abnormally weak in some women. Cervical incompetence or weakness may also be due to a previous injury from a surgical procedure.
   • Muscle weakness during pregnancy might cause the cervix to open too soon, resulting in a miscarriage.
6. Obesity
   • Studies have shown that miscarriage, stillbirth, and repeated miscarriage are more likely to occur if the mother-to-be has a high body mass index (BMI) before pregnancy.

Miscarriage symptoms

Miscarriage symptoms might be different depending on how far along in your pregnancy you are. Sometimes a miscarriage occurs so early and suddenly that the expecting mother has not realised she is carrying a child.

Nonetheless, the most common symptom of a miscarriage is vaginal bleeding. The bleeding can vary from light spotting or brownish discharge to severe bleeding and bright-red blood or clots. Bleeding may occur intermittently.

However, light vaginal bleeding during the first trimester is common and does not necessarily indicate a miscarriage.

Thus, if you are experiencing any vaginal bleeding during pregnancy, do contact your medical practitioner as soon as possible.

Some other symptoms may include:

• Heavy spotting
• Discharge of tissue or fluid from your vagina
• Cramps or severe abdominal pain
• Mild to severe back pain

If you have any of these symptoms during pregnancy, call your doctor immediately. These symptoms can occur without miscarriage, so your doctor will want to run the necessary tests for confirmation.

After a miscarriage

Tests (ultrasound and blood tests) can be done at the hospital to confirm a miscarriage. These tests can also suggest if there is still pregnancy tissue remaining in your womb (called an incomplete or delayed miscarriage) or if all the pregnancy tissue has passed out (a complete miscarriage).

If there are no pregnancy tissues left in your womb, no further treatment is required.

However, if there are some tissues left, you may need to:

• Wait for the tissue to pass out of your womb naturally.
• Take medications to help remove those tissues.
• Have the tissues removed surgically.

Once complete pregnancy tissue is expelled from the uterus, the following measures for a few weeks will help your body heal:

• Have a good rest.
• Avoid strenuous exercise.
• Avoid sexual intercourse.
• Avoid doing heavy house chores.
• Make sure you have a good support system to go through the grieving process.

Pregnancy after miscarriage - precautions to take

If you have experienced a miscarriage, it is best to wait until you are mentally and physically prepared to start trying again for a baby. Be reassured that a miscarriage is not the end, and there is a possibility of getting pregnant again.

However, before trying to conceive again, you may wish to consult your doctor for advice or assistance in creating a conception plan.

In most cases, a miscarriage will not recur. However, if you have experienced two or more consecutive losses, your doctor would likely suggest testing to determine the underlying cause(s) of pregnancy failures.

Some of these tests may be conducted to make sure you have a next successful pregnancy:

• Blood tests to detect any hormone imbalances.
• Chromosome test using blood or tissue samples.
• Pelvic and uterine examinations.
• Ultrasounds.

Even after one miscarriage, you will be closely monitored by your gynaecologist to ensure that your next pregnancy is smooth.

Make an appointment at Gleneagles Hospitals

A miscarriage is something that cannot be completely prevented and is often no one’s fault. It is a very challenging and emotional moment for the expecting parents, but it does not mean that your hopes for creating a family have ended. A vast majority of women have been able to have healthy pregnancies and birth after a miscarriage. 

Do reach out to your healthcare provider to discuss the do’s and don’ts for your next pregnancy and ask as many questions as you need to be sure and confident.
Get in touch with us to book an appointment today if you are planning a pregnancy, or find out more about our Obstetrics and Gynaecology Services at your nearest Gleneagles Hospital. The caring and multidisciplinary team of healthcare professionals are available for consultation and to provide the best care.