A new research from Queen's University Belfast has uncovered the cause of 'unexplained infertility,' providing fresh hope to couples with the condition.
At present one million couples require fertility treatment across the world. Up to one third of these couples are diagnosed with unexplained or idiopathic infertility. This means that, using current tests, neither partner has been diagnosed with any detectable problem.
It is revealed that 80 per cent of couples with unexplained or idiopathic infertility in the large study of 239 couples have a detectable cause known as high sperm DNA damage.
The new study is the first of its kind and will lead to better treatment for these couples, saving them time, money and heartache.
It was studied that the majority of couples experiencing problems with fertility are able to receive an explanation for their infertility. These causes range from low sperm count, poor sperm motility in the man to blocked Fallopian tubes or endometriosis in the woman. Once the causes for infertility have been established the appropriate course of assisted conception treatment can be undertaken.
For almost one third of couples, until now, there has been no obvious cause for infertility and these couples are given the diagnosis of 'unexplained fertility," she stated.
These couples often invest a lot of time and money in fertility treatments like intrauterine insemination (IUI) unlikely to be successful, she revealed.
"In our study we have now had a breakthrough, which explains the cause of infertility for many of those couples. Now that we have found the cause of infertility for these couples suitable treatments can be tailored for them which will direct them straight to the best treatment and increase their chances of having a baby," she added.
The study also showed that the chances of having a baby after IVF is closely related to the amount of DNA damage a man has in each of his sperm. A little damage is normal (under 15 per cent per sperm), as is seen in the sperm of fertile men. But if the damage reaches clinically important levels (high sperm DNA damage more than 25 per cent per sperm) it will reduce the couples' chances of a family, even with some forms of fertility treatment.
The research was carried out using a unique test for male fertility called the Sperm Comet.
The finding was published in Reproductive Biomedicine Online.