How a simple hormone test can reveal early on in pregnancy if women are at risk of miscarriage
Measuring a woman's progesterone levels early in pregnancy could indicate if they were likely to reach full-term
The test was most accurate when combined with an ultrasound
15:54 GMT, 28 September 2012
One in three women experience abdominal pain or vaginal bleeding at the start of their pregnancies, which can be symptoms of miscarriage.
However, up til now there hasn't been a reliable test to tell which of these women will go on to reach full-term.
Now scientists say taking a single hormone test early-on could provide them with the answer.
Scan: Ultrasound found three quarters of non viable pregnancies, but this rose to 99 per cent when combined with a progesterone test
A team, led by Ioannis Gallos from the University of Birmingham, measured the progesterone levels of women who experienced the discomforting symptoms.
They found that in the majority of cases those with a low level of progesterone were unlikely to have a viable pregnancy. Doctors can also use ultrasounds to check viability but results are not always conclusive.
The researchers said combining the two methods gave the most accurate results.
Writing in the British Medical Journal, they said: 'This test is
highly accurate when complemented by ultrasound and could be added to
the existing algorithms for the evaluation of women with pain or
bleeding in early pregnancy as it can accelerate diagnosis.
The scientists analysed the results of 26 studies
involving 9,436 pregnant women who had all be less than 14 weeks pregnant.
Among women who had an ultrasound, 73 per cent had nonviable
pregnancies. But the probability of a nonviable pregnancy rose
to more than 99 percent among women who were also found to have progesterone levels below 3 to 6
nanograms per millilitre.
Of women who didn't have ultrasounds, 96 per cent had nonviable pregnancies if their progesterone levels were below 10ng/ml, while 37 per cent of women with higher levels had nonviable pregnancies.
The scientists stressed there were the odd exception when women had low progesterone levels and continued on to have a baby.
In the UK around one in eight pregnancies end in miscarriage among women who know they have conceived. Around three quarters happen during the first 12 weeks.
It is thought that two thirds of early miscarriages are due to abnormal chromosomes in the baby. Although most do not cause long-term physical problems they can have a devastating emotional impact.