Fertility test

Researchers at Edinburgh University have developed a method of assessing the quality of a sperm before it is used in IVF in order to improve the chances of conception.

The project, which is being funded by the Engineering and Physical Sciences Research Council (EPSRC), uses a technique that identifies individual sperm in order to assess whether it would be able to fertilise an egg during IVF.

The process works by capturing the sperm using highly-focused beams of laser lights to create an ‘optical tweezer’. Once captured, the sperm’s DNA properties are identified using a process known as Raman spectroscopy, which measures the pattern of vibrations using the wavelength and intensity of inelastically scattered light from molecules.

Currently, most techniques assess a sperm's quality by monitoring its shape and activity. Other established tests work by cutting the cells in half and tagging them with fluorescent dye. While this gives a better understanding of its health, the process kills the sperm so that it can not be used in further treatment.

According to Edinburgh University researchers, this is the first time Raman spectroscopy has been used to evaluate DNA in sperm effectively without damaging it in the process. Scientists hope that the technique will improve the current one-in-four conception rate of IVF treatment.

Dr Alistair Elfick, lead scientist on the project, said: ‘In natural conception, the fittest and healthiest sperm are positively selected by the arduous journey they make to the egg. What our technology does is to replace natural selection with a DNA-based "quality score". But this is not about designer babies. We can only tell if the sperm is strong and healthy, not if it will produce a baby with blue eyes.’

Research is currently in a pre-clinical phase; if proved successful the technique could be available to patients within the next five to 10 years.