A British company that sells a "Pink or Blue" home test that tells the gender of a fetus six weeks into pregnancy says it has been sending a couple of test kits a week to Canada.

DNA Worldwide said it is getting dozens of inquiries from Canadians looking for the test of a blood of a pregnant woman. A U.S. company also sells the test online.

"It's a little finger-prick that she puts into her finger and then we take a little blood sample, analyze it in our labs to find out if there's male DNA in her bloodstream," said David Nicholson, director of DNA Worldwide. 

Results come back within four to six days, and the company claims the test accurately shows the gender of the fetus 95 to 98 per cent of the time, if instructions are followed properly. The company began selling the tests online in April.

But less fetal DNA is present in the mother's bloodstream early in pregnancy, said one expert who questioned the technique.

"At six weeks of pregnancy, it's questionable whether the technology is that good," said Dr. Patrick O'Brien, a consultant obstetrician and spokesperson for the Royal College of Obstetricians and Gynecologists.

Ultrasounds at 18 to 20 weeks reveal the gender of the fetus, and an amniocentesis that has a small risk of miscarriage can be done at about 15 weeks in Canada.

People are keen to know the gender early for a variety of reasons, such as deciding what colour to paint the nursery or to tell a dying relative who won't be alive for the birth, Nicholson said.

DNA Worldwide said it won't ship the test to countries such as China or India where sex selection has led to abortions on the basis of gender. In China, females have been abandoned and the country has a gender imbalance of about 120 men for every 100 women.

India banned the use of sex selection technology, though a Canadian-led team of researchers reported last year that 500,000 female fetuses were aborted every year in India over the past 20 years and that the gender selection business has gone underground.

"I think in terms of global commerce these days, they may not market it in particular countries, but it doesn't mean to say the inhabitants of those countries wouldn't be able to get hold of it by some other means," said Tony Calland, who chairs the British Medical Association's ethics committee.

Calland recommends waiting for an ultrasound or until the baby is born to discover the gender.

With files from the Associated Press