An incredibly common but little-known STI could increase the risk of cervical cancer fivefold, researchers warn.
Women’s health experts believe that trichomoniasis, or trich, damages cervical tissue and consequently makes it a “favorable environment” for HPV — responsible for 99 percent of cases of the disease.
An analysis involving nearly half a million women revealed that those infected with the parasite were 80 percent more likely to also have HPV.
Trich usually goes unnoticed because most cases are asymptomatic. However, it can cause discharge from the genitals, as well as pain during urination.
It is more common than chlamydia and gonorrhea in some parts of the world and infects about 180 million people worldwide each year.
You may not have heard of trich, but scientists say data suggests infection from a common, but often symptomless, parasite can increase women’s risk of cervical cancer by 80 percent
Hungarian experts analyzed samples from more than 473,000 women over the past 15 years. The project, said to be the first of its kind, spanned four continents.
The results showed that 8,518 of the women — about 1.8 percent — had trich.
Scientists found that women with trich were 79 percent more likely to also have human papillomavirus (HPV), compared to those who didn’t.
Principal investigator Dr. Balázs Hamar, an expert in obstetrics and gynecology at Semmelweis University in Budapest, said: “This is because the infection causes the inflammation and abruption of the cervical epithelium/cervix, which provides a favorable environment for pathogens such as HPV.”
A smaller subsection of the study, involving 600 women, looked directly at cases of cervical cancer and trich.
It found that women who tested positive for the STI were five times more likely to be affected by the disease than those who tested negative.
For those who had HPV and trich at the same time (1,811 women), their risk of developing cervical cancer was three times higher than those who had HPV alone.
Although the authors said that 90 percent of HPV cases clear up on their own, the risk of developing cancer from an infection increases after age 30.
Other factors, such as smoking or a weakened immune system, also contribute to the risk.
Dr. Hamar added that their results suggest that women who have trich during an STI checkup should also be recommended to have HPV screening.
NHS data shows that use of cervical cancer screening has declined overall over the past year and has now reached a record low of 69.9 per cent
The study, which involved women with an average age of 37, has some limitations, which the authors acknowledged.
Since all women were screened simultaneously for trich, HPV and cervical cancer, it was unclear exactly how the parasite might contribute to the development of the disease over time, the authors said.
They called for further research into the risk of trich and cervical cancer.
Although trich can be difficult to diagnose due to its subtle symptoms, US scientists have recently developed an inexpensive and easy-to-use fingerstick test that can help detect the infection.
Trich is mainly passed between people through unprotected sex or sharing sex toys.
The STI is difficult to diagnose because the symptoms can be so subtle or even non-existent in some people.
If diagnosed, patients are usually prescribed antibiotics that clear up the infection quickly.
According to the National Institute for Health and Care Excellence, around 6,000 cases of trich are diagnosed in the UK each year, with more than 90 percent in women.
The U.S. Centers for Disease Control estimates that there are 2.6 million trich infections in the country each year, with an estimated one in 50 sexually active women and one in 200 men having the STI.
Around 850 women in the UK die of cervical cancer each year.
Although the incidence of the disease has increased in leaps and bounds thanks to the HPV vaccine and regular Pap smears, there are still 3,000 cases per year.
The findings have been published in the International Journal of Gynecology and Obstetrics.
What are the symptoms of trichomoniasis?
Trichmoniasis can be difficult to diagnose as most cases are asymptomatic.
And symptoms that do exist are similar to those of other STIs.
The NHS says you should visit a sexual health clinic if you think you have trichomoniasis.
What are the symptoms?
- Abnormal vaginal discharge that may be thick, thin, or frothy and yellow-green in color.
- Producing more discharge than usual, which can also have an unpleasant fishy smell.
- Pain, swelling and itching around the vagina – sometimes the inner thighs also itch.
- Pain or discomfort when urinating or having sex.
- Pain when urinating or during ejaculation.
- Having to urinate more often than usual.
- Thin, white discharge from the penis.
- Pain, swelling and redness around the head of the penis or foreskin.