Careful who you kiss: virus found in saliva associated with unexplained infertility

JULY, 2016

Alcohol, caffeine and bad diet have all been linked to poor fertility, but up until now no one has blamed the humble kiss.

Now scientists believe they have found a link between unexplained infertility and an obscure virus which they believe is transmitted by kissing.

Researchers have said the discovery offers potential hope for women struggling to get pregnant but without a diagnosis explaining why.

A team at the University of Ferrara in Italy examined the uteruses of women with unexplained primary infertility - the inability ever to bear a child - and found that 43 per cent of them were infected by HHV-6A, one of the human herpes viruses.

The virus was not found in any of the women whose fertility was normal. Infertility affects approximately 6 per cent of women aged from 15 to 44. 

About a quarter of these cases are unexplained, prompting many women to opt for expensive and traumatic fertility treatments, such as IVF, with no way of knowing if they are likely to work.

Published in the journal PLoS One, the study describes how all the women infected with HHV-6A were found to have abnormal levels of cytokines, which are signaling proteins that facilitate interactions between cells that play an important role in supporting fertilized eggs and foetal development.

The scientists also found higher levels of the hormone estradiol, which fluctuates with the menstrual cycle and may trigger the HHV-6A infection.

The virus is typically not detectable in the blood or saliva, so its true prevalence is unknown. However it replicates in the salivary glands and previous research indicates it can be transferred through kissing.

Herpes viruses have previously been implicated in male infertility, but no specific virus has yet been conclusively identified as associated with female infertility.

“This is a surprising discovery,” said Anthony Komaroff, a professor at Harvard Medical School who has studied HHV-6. “If confirmed, the finding has the potential to improve the outcome for a large subset of infertile women.” 

The team say more research is now needed to confirm the findings, which came from a cohort of 66 women, and to determine whether antiviral treatment would help women with the uterine infection.

The study’s senior author, Roberta Rizzo, said she believed the research could lead to a treatment for some infertile women.

In recent months leading clinicians have voiced concerns warning that couples struggling to have a baby are being exploited by fertility doctors.

Dr. John Parsons, founder and former director of King’s College Hospital’s assisted conception unit, said half of all women prescribed fertility treatments do not need help getting pregnant and are at risk of exploitation by private clinics.

Women are entitled to up to three rounds of IVF on the NHS, although in some trust areas they are offered fewer.

Experts have warned that unscrupulous clinics are offering desperate women further rounds of IVF without properly assessing if they are likely to benefit from the treatment.

The fertility watchdog, the Human Fertilization and Embryology Authority, also said it was becoming increasingly concerned about patients prescribing “add-on” treatments which had not been properly tested. The Telegraph