High-risk HPV infections in men could be tied to sperm death, according to a small new study.
Men with high-risk HPV infections appear to be more likely to experience sperm death, which could affect their fertility, according to a small study in Argentina.
Human papillomavirus (HPV) is among the world’s most common sexually transmitted infections.
Most people have no symptoms, but some get genital warts and others go on to develop more serious conditions, such as cervical cancer, which affects about 33,000 women in the European Union every year.
The new study, published in the journal Frontiers in Cellular and Infection Microbiology, adds to a growing body of research about how HPV affects men – and specifically, their fertility.
Researchers from the National University of Córdoba in Argentina took semen samples from 205 men who went to a urology and andrology clinic from 2018 to 2021 and had not been vaccinated against HPV. They found HPV in 19 per cent of the samples, with high-risk infections more common.
They compared semen quality among men with high-risk, low-risk, and no infections, parsed out by cancer risk level. Those with high-risk HPV were more likely to have sperm death, lower white blood cell counts, and higher levels of reactive oxygen species, which are a leading cause of infertility in men.
Notably, there was no connection between HPV infection and other routine markers of semen quality, such as sperm count and motility. And overall, levels of sperm death were still relatively low, meaning men should temper their concerns.
“It is important to note that our study conducted HPV detection at a single time point and HPV is not continuously shed in semen, leaving open the possibility” that some people with negative samples may actually have been infected, the researchers said.
While the study’s sample size is small, the findings offer clues on the cause of fertility issues, which affect an estimated 10 to 15 per cent of couples worldwide.
For example, more oxidative stress in sperm can damage DNA, potentially leading to greater levels of sperm death among men with high-risk HPV infections.
That would help explain why fertility treatments using intrauterine insemination (IUI), where the sperm is placed directly into the uterus, can be less successful, the researchers said.
In some cases, however, developing eggs can repair damage to sperm DNA after they have been fertilised, underscoring that the latest results are promising but far from conclusive.
“The combination of these factors will determine the fate of embryo development, pregnancy outcome, and health of the offspring conceived either naturally or through Assisted Reproductive Technology (ART),” the researchers said.
The study authors also noted that previous research on the link between HPV and sperm quality have had mixed results.
HPV prevention in Europe
Many infected men may not know they have HPV. While women are screened for HPV during pap smears, there is no reliable HPV test for men.
Men are also less likely to get the HPV vaccine. There are major disparities among countries, but overall 39 per cent of European women have received at least one dose, compared with 25 per cent of men.
That could be because the shot was first approved in 2006, but public health agencies have only started recommending it for boys in recent years. Today most European countries recommend the HPV vaccine for both boys and girls, though in Bulgaria and Romania, it is still only advised for girls.