Late c-sections increase risk of future premature births

Tommy’s news, 09/01/2019

Professor Andrew Shennan, Director of the Tommy’s Research Centre in St Thomas’s Hospital, London, is calling for new guidelines for obstetric doctors about the use of c-sections in late labour. This comes after his research showed the increased risk of preterm birth in pregnancies after c-sections.

He found that 14% of women who have a late stage c-section (in the second phase of labour) go on to have a premature birth in a future pregnancy. He compared this to women who did not have a late stage c-section, where only 2% of women went on to have a preterm birth.

Professor Shennan said, ‘Caesarean sections performed late in labour have been linked to a risk of preterm birth in the next pregnancy. When done at full dilatation (in the second stage of labour) the risk is increased 6 fold from 2% to around 15%. The risk appears to continue in future pregnancies. Through our work in the Tommy’s centre, we are looking at how to manage this problem as sometimes late caesareans are necessary in an emergency. For example, women can have cerclage (a cervical stitch) to help reduce future risks.’

As part of the long-term plan, the NHS is committed to reducing the preterm birth rate, and is working with Professor Shennan at the Tommy’s centre to  to achieve this.

‘These research findings will help obstetricians provide best practice care when a caesarean section at full dilatation is required.’ Matthew Jolly, national clinical director for maternity and women's health

C-section benefits and risks

While most women who have a c-section will go on to have healthy future pregnancies, as with any major surgery, there are future benefits and risks with c-sections. In some cases, it will be the safest option for mother and baby but as well as the risk of premature birth in future, other c-section risks can include:

• infection
• bleeding
• problems in future pregnancies, such as low-lying placenta, placenta accreta and pregnancy loss.

Benefits of having a c-section

Women may be offered a planned c-section for many reasons, including problems with the placenta or if a baby is in a difficult position. The benefits of a ceasarean for women who have not had one before include a reduced risk of injury to the vagina and greater bladder control after birth, among others.

An obstetrician should explain the benefits and risks of having a c-section to women, and informed consent should always be given.

Premature birth research

Tommy’s conducts research to find out what puts women at risk of premature birth in order to prevent it.

Each year in the UK, around 60,000 babies are born too soon. The earlier a baby is born the higher the risk of health and development problems, which is why it is so important to find out the cause and take steps to stop it from happening.

Read about Tommy’s current premature birth research.