The same infrared technology that measures fat content in milk can more accurately predict which embryos have the best chance of resulting in a pregnancy, according to fertility experts.

Researchers speaking at the European Society of Human Reproduction and Embryology  estimated their new technique for couples attempting in-vitro fertilisation could help boost pregnancy rates by about 10 per cent to 15 per cent.

In-vitro fertilidation, or IVF, is the procedure commonly known as the test-tube baby treatment.

"We have been trying to look for signals of what embryos are most likely to lead to a pregnancy," said Denny Sakkas, a Yale University researcher and chief scientific officer at U.S.-based Molecular Biometrics, which has licensed the technology.

"Our technology will be used in combination with current techniques."

Researchers have typically looked at the size, shape and structure of embryos to pick those they think have the best chance of resulting in pregnancy, Sakkas said.

Now, they can better the chances of choosing a prime candidate with a new technique that uses infrared light to measure the chemical make-up of the fluid surrounding the embryo.

This gives them a metabolic "fingerprint" they can compare to embryos of successful and failed pregnancy attempts to use when choosing an embryo for transfer, Sakkas said.

The key is matching as closely as possible profiles of embryos that resulted in pregnancy.

"We take these profiles and compare them and look for signals that can give us an indication of when the culture (solution) is likely to give us a pregnancy," he said. "It is like a fingerprint."

With one in six couples worldwide experiencing some form of infertility problem at least once, and with improving technology, more couples are seeking assisted reproductive treatment.

At the same time governments and medical groups are putting pressure on fertility experts to transfer fewer embryos at a time, something that makes it less likely a woman will get pregnant but also cuts the risk of complications, Sakkas said.

"There is more pressure to transfer fewer embryos," he said. "Reducing the number of embryos makes it harder to pick the best ones."

This makes choosing the right embryo even more crucial.

Privately held Molecular Biometrics plans to begin trials of its new test in Europe soon and hopes to make it available to clinics outside the United States in 2009, Sakkas added.

Reuters Health