When we talk about safe sex, the necessity of wearing a condom is usually emphasized — and obviously for good reason. Apart from preventing unwanted pregnancy and STI prevention, researchers in Australia have found that unprotected sex may disrupt the microbiome of the vagina. If you’re wondering what a microbiome is, in this context it refers to the balance of bacteria in the vagina. Now you might be thinking: Gross! Bacteria in the vagina? But we assure you it’s both healthy and normal!
After studying vaginal bacteria in a group of women, Lenka Vodstrcil and her team at the Melbourne Sexual Health Centre concluded that women who had unprotected, penetrative sex with men were “much more likely to have a vaginal microbiome dominated by the species Gardnerella vaginalis and Lactobacillus miners.” This is important because a healthy vaginal microbiome is usually dominated by just one strain of bacteria, and having increased exposure to more can lead to premature birth and urinary tract infections.
As Vodstrcil pointed out, this means that as well as contracting an STI from a sexual partner, women can get sexually transmitted non-pathogenic bacteria from them as well.