Dossier: Pregnancy

Premature birth: risk factors

A premature birth is when a baby is born two or more weeks early. What are the risks of a premature birth – and how can these be reduced?

Text: Julie Freudiger; photo: iStock

In Switzerland, approximately 6 out of 100 babies are born prematurely. Premature means before 37 weeks of gestation are complete, i.e. more than three weeks before the expected due date. Premature babies are much lighter and smaller, their bodily functions are not fully developed and their brain development is less advanced than with babies who are born later, because in the last third of pregnancy alone, the brain volume triples and 40,000 nerve cells are created every minute. Therefore, the earlier a baby is born, the higher the risk of complications. 

However, being born premature today no longer means that the child will be severely mentally or motorically impaired. Even most of the extremely premature babies born before 28 weeks of gestation develop normally in terms of intelligence, although they can be more susceptible to certain conditions such as asthma or ADHD and their memory may be somewhat impaired. Today’s medicine makes many things possible and premature babies often have a good chance of survival despite a bumpy start.

Signs of a premature birth 

Most premature births start spontaneously and without any warning. One clear sign can be regular contractions lasting longer than an hour. Bleeding may also indicate an imminent premature birth. In about one-third of all preterm women, their waters break prematurely. A loss of amniotic fluid, either in drops or all in one go, is a sign of an impending birth. In these cases, the doctor or midwife should be contacted immediately.

Possible causes of premature births

An early birth can also be induced if it is better for the mother and child. If contractions start early or waters break before the due date, the cause is unclear in around half of all cases. However, there are some risk factors that can cause premature births. These include: 

  • Stress, e.g. at work, in a relationship or financial worries
  • Pregnancy-related high blood pressure, diabetes, kidney diseases, thyroid dysfunctions
  • Diseases of the uterus, e.g. fibroids or weakness of the cervix
  • Placental insufficiency, i.e. when the placenta is unable to supply the unborn child with sufficient nutrients and oxygen
  • Too much amniotic fluid
  • Smoking, alcohol and drugs
  • Vaginal, uterine or urinary tract infections
  • Previous miscarriages, premature births or abortions
  • Multiple pregnancies
  • The pregnant woman is younger than 18 or older than 35 years of age

Pregnolia: assessing the risk of a premature birth

The condition of the cervix may give an indication of a premature delivery. During pregnancy, the cervix gets softer and later also shorter. 

Swiss start-up Pregnolia has developed a device that uses a probe to measure the stiffness of the cervix safely, hygienically and painlessly – a very soft cervix can be an indication of a possible premature delivery. Previously, doctors had to do the examination manually and make an estimation.

Sanitas is the first health insurer in Switzerland to cover the costs of a check-up with Pregnolia for women with supplementary outpatient insurance.

More information

Check-ups are important

Some risks can be reduced relatively easily: drugs, alcohol and nicotine should be avoided during pregnancy. A balanced diet and regular moderate exercise can also help reduce certain risks, such as pregnancy-related diabetes. It is also a good idea to shift down a gear in daily life and avoid constant stress and worry. Regular check-ups with a gynaecologist are also important to help prevent premature births. 

If detected in time, an impending premature birth can be delayed under certain circumstances, for example by ensuring that the mother rests or by using medication to inhibit contractions. Whether it makes sense to delay the birth depends on a number of factors. For example, whether the mum’s waters have already broken, whether mum and unborn baby are healthy and how advanced the pregnancy is.