Infertility in men could point to more serious health problems later in life
Poor sperm quality affects about one in ten men and may lead to fertility problems. These men also have an increased risk of developing testicular cancer, which is the most common malignant disease of young males. And, even if they don't develop testicular cancer, men with poor sperm quality tend to die younger than men who don't have fertility problems.
Couples who can't achieve pregnancy usually go to fertility clinics for treatment. At these clinics, emphasis is put on deciding whether the couple needs assisted reproduction or not, and, if so, to choose between different methods (such as IVF, IUI, or ICSI) for doing this. In most cases, these treatments lead to pregnancy and a live birth. So the problem seems to be solved. But if infertility is an early symptom of an underlying disease in the man, fertility clinics won't pick it up.
Testicular cancer is easy to detect. In men seeking treatment for fertility problems, a simple ultrasound scan of the testes can reveal early cancer, so a life-threatening tumour can be prevented. If detected, 95% of all cases can be cured. But, unfortunately, testicular ultrasound scans are rarely performed at fertility clinics as the focus tends to be on sperm numbers and which method of assisted reproduction to use.
And testicular cancer is not the only threat to young infertile men's health. Serious health problems, such as metabolic syndrome (high blood pressure, high blood sugar and obesity), type 2 diabetes and loss of bone mass are also much more common conditions among infertile men. These disorders are possible to prevent, but if left untreated often lead to premature death.
A possible culprit
At Lund University in Malmö, Sweden, we have – together with other research groups – made a number of studies focusing on the link between male fertility problems and subsequent risk of serious diseases. We cannot yet explain the causes, but testosterone deficiency is a strong candidate. My research team found that 30% of all men with impaired semen quality have low testosterone levels. And men totally lacking the hormone have early signs of diabetes and bone loss.
We recently conducted a study in which we investigated almost 4,000 men below the age of 50 and who had had their testosterone measured 25 years ago. We found that the risk of dying at a young age was doubled among those with low testosterone levels compared with men with normal levels of this hormone.
Although testosterone treatment may not necessarily be the best preventive measure, these findings makes it possible to identify men at high risk so that they can be advised about lifestyle changes, such as losing weight or quitting smoking – lifestyle changes that will help reduce the risk of developing type 2 diabetes, cardiovascular disease and osteoporosis.
A relatively high proportion of men get in touch with their doctor about infertility problems and, as they represent a high-risk group for some of the most common diseases occurring later in life, perhaps it is time to change the routines for managing them. With the knowledge we now have regarding these men's health, the least we can demand from doctors is to identify those who are at risk of serious diseases after they have become fathers. This is cheap and only requires simple tests. It is no longer enough to just evaluate the number of sperm.