A new improved method of freezing and storing sperm for future use in infertility treatment has arrived as a boon for couples wanting babies.
According to researchers from Chile and Germany this new technique could potentially improve in vitro fertilization (IVF) treatment and perhaps make it possible for HIV-positive men to donate sperm safely. This method is being used for embryos and eggs and according to Dr. Ian Cooke, emeritus professor of obstetrics and gynecology at the University of Sheffield in England, “this is the next step, so it is logical.”
Mathew Tomlinson, a fertility specialist and scientist at Nottingham University Hospitals in England said, “Any improvements in sperm freezing would be welcome…We can store sperm for many years, but only 25 to 30 percent of sperm survive from even the best samples.” He said this would help cancer patients to store their sperms before they undergo chemotherapy which kills 95% of the sperms. Men with a low sperm count and whose sperm is deteriorating in quality over time would also benefit from the technique.
Leader of the team was Raul Sanchez of La Frontera University in Chile, who with his team found that their alternative freezing approach, known as vitrification allowed almost 80 percent of viable sperms after thawing. Conventionally sperm is frozen slowly and stored in liquid nitrogen. Vitrification involves removing the plasma in sperm, suspending the sperm in a sucrose solution and fast-freezing it in liquid nitrogen. It is then stored in liquid nitrogen or another kind of deep freeze. This procedure also results in greater sperm vitality and motility, and is less damaging to sperm. Also in vitrification, cryopreservation agents are added to lower the water content in cells and prevent ice crystals building up. The team was speaking at a news release from the International Federation of Fertility Societies.
Researchers explained that since the sperm plasma membrane (a possible home to the virus that causes AIDS) is extracted, these sperms may be used to create babies without passing on the illness to a mother or baby.
However Dr. Robert D. Oates, professor of urology at Boston University School of Medicine feels that these claims are theoretical and do not “translate directly into anything related to whether this allows better pregnancy rates.” He said that there was no real proof that these frozen sperms were free of disease. He added, “This is a technique that may have an application… but their claims are way overstated.”
The findings were presented at the World Congress on Fertility and Sterility in Munich, Germany, 12. – 16. September 2010.
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