Male infertility alert over hidden bacteria

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, new research has shown.

While the condition, which usually passes undetected, has long been known to threaten female fertility, scientists from Spain and Mexico have now established that it presents similar risks for men.

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.

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 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 past decade.

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.

“Previously, it was thought that the most worrying thing about chlamydia infections in men was as a conduit for the infection of women. The thing that drives most men to sexual health clinics is symptoms, and chlamydia is often symptom-free. Chlamydia is getting out of control. We have got to encourage men as well as women to go for screening.”

In the study, a team led by José Luis Fernández, of the Juan Cana-lejo University Hospital in La Coruña, examined sperm samples taken from 193 men seeking fertility treatment with their partners in Monterey, Mexico.

Of these, 143 were infected with both chlamydia and mycoplasma, another common sexually transmitted bacterium, while 50 were uninfected and served as healthy controls.

Dr Fernández, who will present his findings today at the American Society for Reproductive Medicine conference in Washington, then examined the men’s sperm for a form of genetic damage called DNA fragmentation. This can cause sperm to die, as well as hindering their ability to fertilise eggs and embryonic development.

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.

“We found there was a three-fold increase in the fragmentation of DNA in sperm cells compared with controls, and this could have a potential role in subfertility,” Dr Fernández said.

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.

Chlamydia causes female infertility as a result of chronic infection, which causes damage to the Fallopian tubes, and once this has occurred it is not usually reversed by treatment.

Men, however, 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.

“After four months of treatment, there was a significant decrease in DNA damage that could improve pregnancy rates in these couples,” Dr Fernández said. “It seems related to an improved pregnancy rate. It’s a very dramatic difference, but this is a small number of couples, so the results are only preliminary.”

The findings suggest that infertility patients of both sexes should be routinely screened for chlamydia, as already happens in most British clinics.

Dr Pacey said: “I would advise couples trying for a baby to be screened for chlamydia. The difficulty is that a positive diagnosis carries implications of infidelity, but of course as it can be asymptomatic the infection could have been there for many years.”

Chlamydia’s effects on female infertility are well-established. If left untreated, up to 40 per cent of women will develop pelvic inflammatory disease, which can cause tubal scarring that leads to infertility and an increased risk of ectopic pregnancy.

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.

Most common sexually transmitted infection

— 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 as the condition often has no symptoms, and can pass undetected for years

— Symptoms can include discharge from the vagina or penis or pain on urination, but it often has no symptoms at all

— A study of male Army recruits found that one in ten had chlamydia, but 88 per cent of these had had no symptoms

— Left untreated, it will cause pelvic inflammatory disease in up to 40 per cent of women. This can cause scarring to the Fallopian tubes, leading to infertility or a raised risk of ectopic pregnancy

— 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 untreated

— Chlamydia can be detected by a simple urine test; swabs are no longer necessary. Postal kits are available from Boots at £25, and a national free screening programme exists for under-25s

Source: Health Protection Agency, Times database
http://www.timesonline.co.uk/tol/life_and_style/health/article2658732.ece

Category: Chlamydia, infertility, Male Fertility, pelvic inflammatory disease, sperm, STDs