Simple test will help predict and prevent premature births

Friday 16 November 2012

Thomas Clarke, born July 2012 at full term

The risk of pregnant women giving birth early can be accurately measured with a simple cervical swab, according to research from Guy’s and St Thomas’, funded by baby charity Tommy’s. This test will reduce distress for women who would otherwise have received unnecessary treatment.

The swab quantitatively measures the level of a protein known as fetal fibronectin (fFN). If the protein leaks out of the womb into the cervix, the likelihood of premature labour is increased. fFN levels reliably indicate whether a woman is likely to give birth prematurely.

The research comes to light just prior to World Prematurity Day – Saturday 17 November – an international awareness day to raise awareness of the 15 million babies who are born prematurely around the world each year.


fFN is already used as an indicator of likely preterm birth, but not in a quantitative way, meaning that many women are treated unnecessarily. Just 5% of those who currently receive treatment go on to give birth prematurely.

“The updated fetal fibronectin test reduces the need for low-risk women to stay in for observation or get treatment when they don’t have to,” says Professor Andrew Shennan, who led the research. “Treatment and transferral to other units can be inconvenient and distressing. This updated test is more precise, so we can give a more definitive diagnosis.”

Personal experience

Susan Clarke, 34, was at risk of losing her baby following two miscarriages, and was referred to the Tommy’s-funded Preterm Surveillance Clinic at St Thomas’. The tests showed that she had very low levels of fFN, so the chances of her going into labour prematurely were very small. “The low fFN readings gave us peace of mind and meant we could keep the stress levels down,” says Susan, who gave birth to Thomas at 38 weeks.

 Sally Campbell, 42, was 27 weeks pregnant when her fFN test came back positive. As this meant she was likely to give birth prematurely, she was given an injection of steroids to encourage her baby’s development, and sent home to rest. This careful management of her pregnancy meant that Sally ended up carrying her daughter, Missy, to term. “Staying at home was hard for me, as I’m an active person and I had to stop working,” says Sally. “But it was worth it for Missy. I don’t think she’d be here if it wasn’t for the test and the care from Professor Shennan and his team.”

How it works

The fFN test uses equipment known as the 10Q analyser, developed and produced by Hologic. The new version accurately determines the level of risk and provides a definitive answer in 10 minutes (the old version of the 10Q analyser takes 23 minutes and is not quantitative).

The updated version of the 10Q is already installed at 134 hospitals but Guy’s and St Thomas’ NHS Foundation Trust is the first to use its more accurate, quantitative capabilities.

“The test is so speedy,” says Susan. “After the sample was taken, I would get changed, grab a cup of coffee and the results would be ready.”

Premature birth is increasing

In the UK, 7.8% of babies are born prematurely (60,000 per year), and this number is on the rise. This could be due to higher incidences of chronic diseases such as diabetes and hypertension, or the growing trend for later motherhood.

Women at high risk of giving birth prematurely may be prescribed bedrest; given medication to relax the uterus; and/or have a cervical stitch. If they are more than 24 weeks pregnant, they can be given steroids that help to mature the baby’s lungs.

Jane Brewin, Chief Executive of baby charity Tommy’s, says: “Premature birth affects a huge number of families each year and can have devastating consequences for many families.  As such we devote much of our current research to identifying women at risk, and preventing it from happening in the first place.  We are delighted that the funding we provide enables research and medical advances like this predictive test, to ensure women receive the best care possible, and their babies the best start in life.”

Cost savings

Another benefit is that the improved fFN test should lead to significant cost savings for the NHS. “For each patient in our pre-term clinic, we saved an average of £1,800 because many women didn’t receive unnecessary treatment; and most importantly they all received more appropriate care,” says Professor Shennan.

With nearly 60,000 premature births per year in the UK, the national uptake of this new test could lead to national NHS savings of over £100 million a year. 

The research was funded by Tommy’s, which funds medical research in to pregnancy complications such as premature birth, stillbirth and miscarriage.  The charity also produces a free guide called ‘Having a Premature Baby’, for parents at risk of having, or who have had, a premature baby.

Further information

  • The research paper is will be published online today (Fri 16 Nov) on the American Journal of Obstetrics and Gynaecology website
  • Statistics about preterm birth:
    • Over 90% of high risk women seen at clinic have had a healthy baby at full-term, compared to national average of 50–70%
    • Total cost of preterm birth to NHS is £2.9billion a year, equivalent to that of smoking, alcohol and obesity. Reducing the rate of preterm birth even by a small amount, will have a significant impact on reducing this cost
    • Using the fFN as routine screening for all women at the pre term clinic has reduced cost per admission by 35% despite increased workload – this is because the women identified as not at risk by a negative test can be discharged
  • Tommy’s free guide, Having a premature baby, funded by the Asda Foundation, is available to download from , funded by the Asda Foundation, is available to download from
  • World Prematurity Day, 17 November 2012, is a global movement to raise awareness about prematurity highlighting the burden of preterm birth

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