7 December 2009
Appeared in BioNews 537Men suffering from from non-obstructive azoospermia (NOA), meaning they have undetectable levels of sperm in their semen, which is not caused by an obstruction in their reproductive system, have long been considered poor candidates for IVF. However new research published in the online journal of Reproductive Biology and Endocrinology has reported that NOA sufferers could be just as capable of producing viable embryos as other men.
Approximately one per cent of the male population and 10 per cent of men seeking fertility evaluation have testicular failure. Previous research conducted by Belgian scientists reported lower pregnancy rates than normal (approximately 20 per cent) when using sperm from NOA patients. It has also been thought that sperm isolated from NOA patients, while able to produce embryos, is less capable of producing live births and that the incidence of genetic mutations may be higher resulting in congenitial deffects. However, new research contradicts this and gives hope that men with NOA can be just as likely to father a child.
Nina Desai and her team at the Cleveland Clinic Foundation analysed 156 intracytoplasmic sperm injection (ICSI) cycles which used sperm taken from the testes of 44 men suffering from obstructive azoospermia (OA) and 17 men diagnosed with NOA. For their study they assessed embryonic development, implantation, pregnancy and live birth rates. They found on all counts that there were no significant differences between the groups.
Desai and her team analysed the ability for the pateranl sperm to iniate genomic activation, this is when the genome of the embryo divides and begins to arrange itself. They way to morphologically measure this is to observe the degree of cell to cell aderence as the embryo cells divide, if there is genomic activation it is thought that by the eight-cell stage there will be an increase in cell-cell adherence. The anaysis found no differences between the sperm groups suggesting that the genome activation is independent of sperm origin and type of azoospermia. They also noted that there were no cogenital abnormalities in the 115 healthy births.