New Test Tells Gender of Baby at 7 Weeks
A new test can tell a baby's gender at just seven weeks.
A blood test which looks for foetal DNA in the mother's blood can be carried out on expectant mothers to accurately decide if the baby is male or female.
Parents-to-be wanting to find out their baby's gender can be assured that a blood test on the mother gives an accurate result, say scientists.
The tests are sold privately in many countries, including the UK. US experts examined over 6,000 test results and found it was reliable 98% of the time - providing it was used after the seventh week of pregnancy.
If the test is used earlier than seven weeks into the pregnancy the results are less reliable.
Routine ultrasound scans can only give a gender prediction at about 12 weeks so thanks to the new test, parents-to-be are able to find out the sex of their baby a month earlier. This is particularly helpful to parents who need to know the sex of their child for medical reasons (for example, to see if their baby will be affected by an inherited disorder which only affects boys.)
Some hospitals, like Great Ormond Street, already use the tests to help detect male babies that could have haemophilia.
Critics of the tests argue that the blood tests could be used in a negative way for family balancing. If a couple already have three boys they might only want to continue with the pregnancy if they find out they are having a girl.
Dr Gillian Lockwood, medical director of Midland Fertility Services, said: "In the UK we would not normally approve of someone who decided to terminate because it was a 'blue' pregnancy rather than a 'pink' one.
"Sex selection for social reasons is illegal in the UK. But there's the danger that this is part of a slippery slope."
The review, which looked at 57 studies representing 6,541 pregnancies, found the blood tests gave a genuine result 95% of the time and that this result was correct 98.6% of the time. So, out of 100 couples, only a few would be left not knowing with certainty the sex of their baby.
Professor Richard Fleming, of the Glasgow Centre for Reproductive Medicine, said it was important to have confirmation that the tests are valid.
He said it could help doctors check for sex-linked genetic conditions earlier. But he said the technology was likely to be used for social reasons.