HEALTH BRIEFING:SCIENTISTS IN the US have developed a method to select only the best sperm when employing in vitro fertilisation. The technique is almost as good as the ultimate arbitrator of sperm suitability – the egg itself.
A team from the Yale School of Medicine said indicators such as sperm numbers and motility were the usual measures used to assess fertility, but these provided no information about subsequent attachment to the egg.
“We have now found a biochemical marker of sperm fertility so that we can select sperm with high genetic integrity,” said Dr Gabor Huszar, director of the sperm physiology lab and a senior scientist in Yale’s Department of Obstetrics, Gynaecology and Reproductive Sciences.
In an ideal situation, the egg naturally chooses the optimal sperm, allowing it to enter while blocking off others. In vitro fertilisation interferes with this process, however, and it was not known whether the best sperm would win out.
The team tested the idea that high quality sperm might bind to a substance known as hyaluronic acid. They tested sperm from 50 subjects, with part of a sample allowed to bind to the hyaluronic acid marker. Those that did bind were compared to those that did not bind using a range of test methods.
They found that there was a link between the ability of sperm to bind to the acid and their overall genetic integrity. Dr Huszar likened those that did not bind to scratched CDs. "They seem to be operational but when you play them, some of the information is missing," he said. Those that could bind were found to be genetically optimal, the scientists write in the Journal of Andrology.
WHO to decide today if the H1N1 flu outbreak is over
AN EXPERT panel advising the World Health Organisation will meet today to decide whether to declare that the H1N1 influenza outbreak is finally over.
The WHO said yesterday that its emergency committee would begin a teleconference at noon today on its website. It is to consider three potential options in terms of the flu outbreak.
It can decide the pandemic is still active and that the WHO must maintain its current high alert response; it can decide the pandemic has moved into a transitional “post peak” phase; or it could declare that all danger has passed and the pandemic is finally over.
It is no small decision to make given WHO guidance on the status of a pandemic determines how its 193 member governments respond to issues such as disease monitoring, vaccine stockpiling and the provision of medical resources should an outbreak occur.
The WHO, as the committee conducts its deliberations, will also be mindful of the criticism it has faced about exaggerating the dangers of the H1N1 outbreak. It was declared a full pandemic in June 2009 after its first emergence in April of that year. H1N1 or the swine flu caused a confirmed 18,000 deaths, according to the WHO. It believes the death toll from the virus to have been much higher however.
The virus is currently most active in parts of the Caribbean and southeast Asia with some activity in parts of Chile.
The emergency committee's review had been on hold until the onset of the southern hemisphere winter. This would allow time for any changes in the flu's virulence to be assessed before making a decision today. – Additional reporting Reuters
‘Too posh to push’ is a myth, study finds
IT IS not a matter of "too posh to push" as very few mothers ask for a Caesarean section, researchers have found. "There is a misconception that the overall increase of Caesarean births is the result of maternal request," say the authors of a Canadian study in Obstetrics & Gynaecology. The University of British Columbia analysis showed that just 2 per cent of women sought Caesarean, although there were strong regional differences, with some areas more likely than others to perform the procedure.