New research has shown that chlamydia, the sexually transmitted infection (STI) carried by one in ten sexually active young British adults can make men infertile by damaging the quality of their sperm.
Men with chlamydia have three times the normal number of sperm with genetic damage that can impair their ability to father children, the study found.
If you are worried that you could have chlamydia it is now possible to get a home test for chlamydia and send a urine sample away for analysis.
Antibiotic treatment can reverse the effect, and preliminary results indicate that it may dramatically enhance pregnancy rates when couples are trying for a baby. But the discovery suggests that the prevalence of the disease may be contributing to infertility across an entire generation of young adults.
Britain’s national screening programme has found that 10.2 per cent of both men and women aged 18 to 25 carry the bacteria, and studies have found infection rates as high as 5 per cent among older groups with a lower risk.
The findings indicate that untreated chlamydia infections should not just concern women, who have long been warned that the condition can make them infertile, but it has direct consequences for men.
This will create fresh pressure for chlamydia screening to be more effectively targeted at young men, who rarely seek testing and treatment unless they develop symptoms, which are often absent or quickly fade.
Doctors have already warned that the rise in the number of chlamydia cases in Britain may rob thousands of young women of the chance to have children.
Figures from the Health Protection Agency reveal that cases of chlamydia have increased by more than 200 per cent in England in the last ten years.
Chlamydia is easily treated with antibiotics, typically a week’s course of doxycycline or a single dose of azithromycin, but testing is necessary first.
Allan Pacey, senior lecturer in andrology at the University of Sheffield and secretary of the British Fertility Society, said that the emerging understanding of how chlamydia affects male fertility should change the way that society approaches the condition.
"We might think of chlamydia as a disease that damages female fertility, but we need to think again," he said. "It does damage female fertility, but it appears to damage male fertility, too.
Chlamydia is getting out of control, men as well as women need to be encouraged to go for screening.
In the new study, sperm samples were taken from 193 men seeking fertility treatment with their partners.
Of these, 143 were infected with chlamydia while 50 were uninfected and served as healthy controls.
An average of 35 per cent of the infected men’s sperm was damaged, a proportion 3.2 times higher than in the healthy controls.
In the infected group, both partners were treated with antibiotics. During the early stages of treatment, just 12.5 per cent of the couples conceived but, when therapy was complete, 85.7 per cent had achieved a pregnancy.
Successful treatment of the male partners is more likely to have been responsible for this effect.
Men produce new sperm so quickly and in such abundance that removing the infection will rapidly improve sperm quality. After treatment, the infected men produced many fewer genetically damaged sperm.
The findings suggest that infertility patients of both sexes should be routinely screened for chlamydia, as already happens in most British clinics.
Couples finding difficulty in conceiving should be screened for chlamydia. A positive diagnosis may carry implications of infidelity, but because chlamydia can be present without symptoms, the infection could have been there for many years.
In men, chlamydia can lead to swelling of the testicles or epididymis, and either can cause sterility if not treated. However, both conditions are generally treated before they cause long-term damage, as they are painful.
Some facts about chlamydia:
- Chlamydia is caused by the bacterium Chlamydia trachomatis
- It is the most common sexually transmitted infection in Britain, with 109,958 confirmed diagnoses in 2005, and the incidence is increasing
- The true figure is thought to be much higher because the condition often has no symptoms and can pass undetected for years
- If there are symptoms, these can include discharge from the vagina or penis or pain on urination
- A study of male Army recruits found that one in ten had chlamydia, but 88% of these had had no symptoms
- In men, it can cause epididymitis or orchitis - swelling of the epididymis at the top of the testicle, or of the testicle itself. This is painful, and can cause scarring and infertility if left untreated
- Chlamydia can now be detected by a simple urine test that can be taken at home.
For more information on the home test for chlamydia please click here
