Canadian gynaecologist Dr Jen Gunter says this is because washing with a cucumber upsets the natural pH balance of your intimate bits.
Furthermore, she said that it will in fact cause a bad smell as she warned 'if you have a vagina you should definitely not do this'.
'This idea that some kind of vaginal cleansing is required, be it a peeled cucumber or the "feminine washes" sold at drugstores, is misogyny dressed up as health care and I am having none of it,' she wrote on her blog.
"Vaginas are not dirty. Study after study after study tells us that douches, cleanses, steams, vinegar, pH balancing products, aloe, colloidal silver, garlic or whatever else passing as the vaginal snake oil du jour at best do nothing but have real potential for harming good bacteria or disrupting the mucosal surface.
"By damaging lactobacilli and the mucosa, attempts at vaginal cleaning increase a woman's risk of contracting gonorrhoea or HIV if she is exposed.
"Paradoxically, it will also cause odour."
And cucumbers are not the only strange thing women have been putting in their vaginas - women were reportedly 'glitter bombing' their vaginas which experts said was dangerous.
Risk of fungal infections
Dr Gunter also warned that all kinds of fungi, and other bugs that can be picked up in a vegetable patch, could end up thriving in your vagina.
She added: "Cucumbers seem prone to all kinds of nasty fungi and I just don't think anything capable of getting blossom end rot [a type of vegetable rot] should go in a vagina.
"All in all I'd say it's probably wise to not introduce an object with unknown plant microorganisms into your vagina.
"And no, a little wash in the kitchen sink it's going to sterilise the cucumber."
Vaginas are 'self-cleaning'.
She stresses that women should be assured that douches are unnecessary as vaginas are designed to clean themselves.
Dr Gunter even posted a Tweet to say: "A vagina takes care of itself. Like a self cleaning oven."
If you want to assist it or are worried about odour, experts advise water and a mild soap is best just around he outside of your genital area.
But studies suggest applying irritating products inside their intimate areas poses health risks.
Women who douche are twice as likely to develop ovarian cancer, a national US study in 2016 by the National Institute of Environmental Health Sciences revealed.
And previous research also found that women who use shower gels and soaps in intimate areas are putting themselves at higher risk of developing sexually transmitted infections.
Researchers at the University of California, Los Angeles, say that soaps and lubricants can damage sensitive tissues and raise a woman's chance of becoming infected with herpes, chlamydia and HIV.
Study leader Joelle Brown said there is "mounting evidence" that using these products internally can increase the risk of bacterial vaginosis - a condition that occurs when the bacterial balance becomes disrupted - and sexually transmitted infections.
WHY IS THE PH OF YOUR VAGINA IMPORTANT?
Scientists have discovered an STI and HIV-fighting bacteria naturally present in some women's vaginas.
L. crispatus bacteria in their vaginas is one of five types of bacteria present in female genitals.
But unlike in the gut - where we strive to have a mix of bacteria - many researchers believe the vagina is healthiest if just one (L. crispatus) is dominant.
Lactobacillus bacteria pump out lactic acid, which keeps the vaginal environment at a low, acidic pH that kills or discourages other bacteria, yeast and viruses from thriving.
There are even hints that certain Lactobacillus species reinforce the mucus in the vagina that acts as a natural barrier to invaders.
DON'T GLITTER BOMB YOUR VAGINA EITHER WARNS EXPERT
A leading gynecologist has spoken out against the bizarre trend for women to glitter bomb their vagina.
It comes after online retailer Pretty Woman Inc revealed it is selling "Passion Dust intimacy capsules" filled with candy-scented glitter - and it had sold out of stock in a matter of days.
The product description on the website says: "It is a small capsule that you insert into your vagina and allow it to naturally dissolve and release it's contents" - with a disclaimer to users that it does not cause any magical or supernatural sensations.
Dr Jen Gunter, a leading doctor based in Canada, warns this unusual concept is guaranteed to lead to a dangerous infection.
By throwing off the delicate balance of your vagina's bacteria, it could also increase your risk of catching a sexually-transmitted disease, she warns.
'Just because something is safe for your lips, for example glitter lip gloss, doesn't mean it is safe for the vagina,' Dr Gunter warns readers on her blog.
Dr Gunter warns there is, to date, no known way of making a vagina-friendly glitter.
The website says Passion Dust is made of gelatin capsules, starch based edible glitter, acacia (gum arabic) powder, Zea Mays starch, and vegetable stearate.
Dr Gunter warns this could cause a nasty inflammatory vaginal discharge and/or an inflammatory mass in the vaginal wall.
Most importantly, edible glitter contains sugar.
"Depositing sugar in the vagina lets the bad bacteria go wild," she writes.
