Causes of Infant Loss and Stillborn Births During Pregnancy and How to Minimise Risks

Published 14th October 2020 | Dr Ujwala Parashar

Pregnancy is a time of great joy, but for some, it can become a time of great sadness due to infant loss during pregnancy and still born births.

This article has been written  for “Pregnancy and Infant Loss Remembrance Day” which occurs on the 15th October as a resource to raise awareness, provide education, and minimise risk.  

What are the statistics?

The current statistics tell us that everyday in Australia, a miscarriage occurs every 3.5 minutes; 6 babies are stillborn; and 3 babies die within the first 12 months of birth.

What is a miscarriage?

A miscarriage is a loss of a pregnancy and is the term that is generally used when the loss has occurred before 20 weeks of gestation. Most miscarriages occur before the 12th week of gestation in the first trimester of the pregnancy and are also referred to as a “spontaneous abortion.”

Unfortunately, approximately 15-20% of known pregnancies end in miscarriage.

Why do miscarriages happen?

Genetic Causes

The most common cause of miscarriage is genetic and is caused by a problem with chromosomes that allow normal development in a foetus. Approximately 50% of all first trimester miscarriages are due to chromosomal abnormalities. Unfortunately, the factors that lead to these are unavoidable. 

During conception, the sperm and egg meet and the cells come together; they then commence to divide and form the genetic material that makes an individual person.

We are each supposed to have 46 total chromosomes made up of 23 from each parent. During the process of cell division, a cell may be missing or repeated. Chromosomal abnormalities can occur more frequently in women who are considered of a more advanced maternal age, or older than age 35 at pregnancy term. 

If the miscarriage is due to genetic causes, it cannot be prevented in most cases. However, for future pregnancies, your obstetrician can provide testing, management, and lifestyle modifications to further assist a healthy pregnancy.


Infections of the cervix or uterus during pregnancy can be dangerous to a developing baby and may lead to miscarriage. Some other infections that may be passed on to the baby or the placenta can also impact on a developing pregnancy and may result in infant loss. Some of these infections include:

Listeria. This is an infection caused through food. Prior to conception, women should request  a pregnancy healthy eating diet that will guide the right food choices to avoid the contraction of listeria.

Parvoviris B19. This is usually not a high risk as approximately 50% of pregnant women are immune, and if not immune, most women will usually only have mild symptoms. However, if you are exposed to parvovirus B19 during pregnancy, contact your obstetrician as soon as possible.

Rubella. Rubella (otherwise known as German Measles) is very dangerous during pregnancy, particularly in the first 12 weeks, and can result in infant death or severe health defects. All women of child-bearing age should ensure they have been immunised for rubella before conceiving. If you are not sure if you have been immunised for rubella and want to conceive or have conceived, speak to your healthcare professional for advice on next steps.

Herpes simplex. If you have herpes prior to conception, there is a low risk of transmission to your baby. However, if you are pregnant and contract genital herpes, it is important to advise your obstetrician so that proper preventative measures can be put into place.

Thyroid Conditions

The conditions of Hyperthyroidism and Hypothyroidism can affect a healthy pregnancy and foetal development. Women have an increased risk for a thyroid condition during pregnancy if they:

Are currently being treated for a thyroid condition; have thyroid nodules or have a goitre.

Have previously had a thyroid condition or have a baby with a thyroid condition.

Have an autoimmune disorder or a family history of disease including Graves’ or Hashimoto’s disease.

Have type1 diabetes.

Have undertaken treatment for hyperthyroidism.

If you have any history of thyroid conditions or have a family history, this should be addressed with your obstetrician and discuss a physical exam and blood test to check the levels of thyroid hormones and thyroid stimulating hormone. Your thyroid levels can then be managed during the term of your pregnancy to avoid harm to your developing baby.

Clotting disorders

Lupus anticoaglulant antibodies. This is a disorder in which the body creates antibodies to fight normal components of human blood cells. As a result, tiny blood clots can be caused that can lead to pregnancy complications and may result in miscarriage.

There are no symptoms for lupus anticoagulant, but If you have had recurrent miscarriage or blood clots, tests can be undertaken to diagnose if you have this condition and suitable treatment can then be instituted.

Antiphospholipid syndrome. This can result in thrombosis and pre-eclampsia. You may be more susceptible to this condition if you have had:

Blood clot in a deep vein or artery.

Low platelet count.

Stroke or mini-stroke.

Blood clot in the lungs.

Unexplained miscarriages.


Livedo reticularis.

When you are considering pregnancy, you should discuss with your healthcare provider any history of blood clots and previous pregnancies. If there is a suspicion of clotting disorders, tests can be undertaken and treatment plans put in place for ongoing management during your pregnancy.

Complications and causes for possible infant loss in second trimester: weeks 13 – 28

The second trimester is generally when women feel best during their pregnancy as nausea and vomiting has usually resolved and the risk of miscarriage has dropped to 5 percent. However, there are some complications that can occur, and can be prevented from occurring in the first instance.

Vaginal bleeding

Although miscarriage is less common in the second trimester, it can still occur and the first warning sign is vaginal bleeding. This can be the result of multiple factors including:

Uterine septum. 

Incompetent cervix.

Autoimmune diseases.

Chromosomal abnormalities.

There are other possible causes of vaginal bleeding in the second trimester which include:

Early labour.

Problems with the placenta.

It can be traumatic to experience vaginal bleeding during pregnancy, but it does not mean that you will miscarry. 

If you experience any vaginal bleeding, try to relax, keep calm, and seek immediate care through your health professional who will arrange for an examination. Possible treatment may include bed rest until the bleeding stops.

Complications and causes for possible infant loss in third trimester: weeks 28 - 40

This is the most exciting time of pregnancy; however, complications may still occur. Prenatal care during the third trimester is particularly important as the types of complications that can arise are more easily managed with early detection. 

During your third trimester, you should be maintaining more regular visits to your obstetrician; ideally fortnightly from week 28 – 36 and weekly from there till the birth of your baby. 

Some complications that can arise during third trimester include:

Gestational diabetes

This occurs due to the hormonal changes in a woman’s body during pregnancy which makes it more difficult for the body to effectively use insulin. Most women will have no symptoms of gestational diabetes; however, it is dangerous for the developing baby and can result in complications; in particular, excessive growth of the foetus which increases the likelihood of caesarean section delivery.

It is important for women to ensure testing for gestational diabetes in the beginning of the third trimester (weeks 24 – 28) to allow for proper management and treatment of the mother and foetus if detected. Treatment includes modifications to diet such as decreasing intake of carbs and an increase of fruit and veges, lifestyle changes - including the adoption of suitable regular low impact exercise, and in some instances, medicines.


Preeclampsia is a serious condition that typically occurs after week 20 of a pregnancy and affects between 5 – 8 percent of women. It can result in serious complications and death for both the mother and the baby. 

It is important to ensure regular prenatal visits during the third trimester to monitor the onset of preeclampsia.

The symptoms of preeclampsia include:

High blood pressure.

Protein in the urine.

Sudden weight gain.

Swelling of hands and feet.

If you are experiencing any of these symptoms it is important to arrange for a consultant with your doctor as soon as possible.

Other conditions of preeclampsia include the following. If you experience any of these symptoms you must seek immediate emergency medical assistance.

Rapid swelling of the feet, legs and hands or the face.

Loss of vision.

“Floaters” in vision.

Severe pain on your right side or around your stomach.

Easy bruising.

Lower levels of urine.

Shortness of breath.

Treatment for preeclampsia varies depending upon the severity of the symptoms and how far along the pregnancy is. In some instances, it may involve the delivery of your baby to ensure the protection of you both.

Preterm labour

This occurs when contractions that cause cervical changes occur before week 37 of the pregnancy. Women at greater risk for preterm labour include:

Women pregnant with multiples (twins or more).

If there is an infection of the amniotic sac.

If there is an excess of amniotic fluid.

If there has been a previous preterm birth.

Symptoms of preterm labour

The symptoms of preterm labour can sometimes go unnoticed as they are subtle and can be overlooked as a normal part of pregnancy. Look out for the following symptoms:


Frequent urination.

Lower back pain.

Tightness in the lower abdomen.

Vaginal discharge.

Vaginal pressure.

It is not fully understood what causes preterm labour, however each day a pregnancy is prolonged increases the chance of a healthy baby. If preterm labour commences after 36 weeks, the baby is usually delivered as the possible risks of lung disease associated with a premature delivery is very low.

 If you are concerned that you may be experiencing preterm labour symptoms, contact your obstetrician. 


Stillbirth is the term used for the loss of a baby from 20 weeks gestation, or at 400 grams body weight if the gestation is unknown.

Data in a report of 2019 from the Australian Government Institute of Health and Welfare looking at improvement in outcomes advises that there were 4,263 stillbirths in Australia in 2015 and 2016. This equates to 1 in 135 pregnancies: with 60% occurring between week 20 and week 26, and with indigenous women having a 50% higher risk rate of stillbirth than non-indigenous women.

What are the causes of stillbirth?

There is a lot unknown about what causes stillbirth, and approximately 20% of stillbirths are unexplained. The causes of stillbirth are listed as being:

Congenital abnormality.

“Unexplained death”.

Premature birth.

Perinatal conditions.

Maternal conditions.

What are the risk factors for stillbirth?

The risk factors include:

The mother’s age. Risk is higher in women under the age of 20 years and over the age of 40 years.

Smoking during pregnancy.

A previous stillbirth. Women who have had a previous stillbirth are 3 times more likely to have another stillbirth.

Pre-existing diabetes.

High blood pressure (also known as hypertension).

Women with a BMI over 30.

There are other risk factors for stillbirth, and it is recommended that each women review her risk profile and if you fall into any of the listed criteria, discuss your concerns with your obstetrician to ensure these risks are carefully monitored during pregnancy.

Positive, preventative measures

If you are planning to conceive, positive preventative measures, pre-planning and regular consultations with your obstetrician is the best opportunity for a healthy pregnancy and a defence against infant death. 

Be aware, plan, adopt change and monitor

Pre-plan a program suitable to your health and family history with your obstetrician and adopt the following positive changes to your lifestyle during pregnancy to help ensure a healthy pregnancy and a healthy baby.

Do not smoke.

Do not drink alcohol.

Do not use illicit drugs.

Commence taking folic acid.

Eat a well-balanced healthy diet.

Have a regular exercise regime.

Reduce stress and anxiety.

Ensure regular visits to your obstetrician.

Dr Ujwala Parashar, Obstetrician & Gynaecologist

Sam Samant

Dr Ujwala Parashar is a highly trained female obstetrician and gynaecologist with over 15 years of professional experience and training, practicing in Sydney's North Shore and Barangaroo. If you would like more information on conception, or if you are seeking obstetric options and advice, please contact us or call 1300 811 827 to arrange a consultation with her.