Midwife reveals what bleach-like stains in your underwear really means for your vagina

WE’VE all got that one pair of knickers that we wear during our time of the month.

And for most, it’s a pair that have got bleach-like stains in that we just can’t get out.

The sensation has been rife over social media, with many taking to platforms like TikTok to share their theories on where the stains comes from.

But now one midwife has put all the rumours to bed and has finally explained what they are caused by and what the marks could mean for your vagina.

Rebecca Ingalls, midwife and women’s-health nurse practitioner in New Hampshire, US said that before you hit menopause, a healthy vagina is meant to be acidic.

She explained that this acid is created by helpful microorganisms called lactobacilli, which defend against harmful microorganisms.

Most substances that include water have a pH level and this indicates how basic or acidic it is.

The vagina is self cleaning and one way it does this is by keeping at a pH of 3.8 to 4.5.

This means that healthy discharge will be slightly acidic, Rebecca told Insider.

The reason your underwear changes colour and has that bleach type mark is because cotton is sensitive to acid.

But what does this acid mean for your vagina?

Rebecca explained that while a higher pH isn’t always a problem, it can be a sign that some lactobacilli are few or absent and that the vaginal environment is out of balance or is experiencing an infection.

However, she added that this doesn’t mean you should start cleaning the vagina inside.

“Only outside, with water and mild, fragrance-free soap — to keep the lactobacilli plentiful so the vagina can clean itself with the acidity,” she said.

It’s normal for the consistency of your discharge to change through your cycle.

Often during the ovulation phase it will become stickier and sometimes, you might smell a little different down there, she said.

However, there are some instances when you might have to see a medical professional, the midwife said.

This includes if your vagina or discharge has taken on a particularly pungent smell.

You should also seek help if it takes on a new colour of if you become itchy down below, the NHS states.

These could be signs of a yeast infection or bacterial vaginosis, which have different pH levels to a healthy vagina, Rebecca added.

Experts at the Vagina Museum previously highlighted that the bleach stain in your knickers is “completely normal”.

In a post on Twitter they revealed several pairs of knickers which had the strange stain.

Reassuring their followers they said: “The light patches in underwear isn’t staining from period blood or discharge, it’s bleaching – the same as if you’ve ever tried putting lemon juice in your hair to lighten it.

“It’s not a sign of dirtiness or bad hygiene to have paler patches in your pants, it’s something which happens when the acidity of a perfectly healthy vagina spends time in contact with fabric, and it’s particularly noticeable on darker fabrics.

“So, it’s not just you. Lighter patches in your knickers are normal, and there’s nothing to be ashamed of!”