15 February 2012
A handheld device for predicting whether pregnant women are at risk of giving birth prematurely is to undergo large-scale clinical trials.
Researchers at Sheffield University developed the pencil-size electrical probe following research into changes that occur in the cervix of women who experience premature or ‘preterm’ births, which can appear weeks before labour occurs.
If the device is found to be successful — and initial trials indicate it could detect risk of premature birth in up to 95 per cent of cases — it would enable doctors to know whether to prescribe treatments or transfer women to specialist units.
‘There are some interventions, including drug treatments, which have been shown to prolong gestation by a variable period of days to weeks or even months,’ research leader Dr Dilly Anumba, a clinical senior lecturer at Sheffield, told The Engineer.
‘What has never been clear is which women benefit the most from this treatment and who ought to have it. So we are hoping this device will help us to determine those women who will benefit from such treatments as progesterone therapy.
‘We could also potentially stop admitting women to hospital who don’t need to go to hospital, with substantial cost savings both to the NHS and the wider world.’
The device uses electrical impulses to measure changes in the resistance of cervical cells, which are an indicator of whether a women is at risk of most types of premature birth and can be detected from 20 to 22 weeks into a pregnancy.
Cervical tissue changes that occur weeks or months before preterm birth, such as an influx of inflammatory cells that causes strengthening collagen material to degrade, affect the relationship between cells and this alters their patterns of electrical resistance.
The researchers created a device to measure the changes in this spectrum while discriminating between different tissue types within the cervix.
‘The device obviously has to be small to access the uterus and the challenge of squeezing all that technology into a small probe was significant,’ said Anumba.
‘We’ve then also had to overcome the problems of tissue fluid and the effect that it can short-circuit electrical devices, and other things such as the differences in the types of cellular lining of the cervix has also been an issue.’
If the device can also recognise functionally weak cervixes, it could potentially be used to identify women at risk of late-term miscarriages.
The Medical Research Council is funding a £620,000 trial of 500 women at Sheffield’s Jessop Wing Hospital to test the device over the next two years.
The National Institute for Health Research, which coordinates research for the NHS, is also funding the trial of a second device that works slightly differently but is at an earlier stage of development.