It’s important to understand that this is completely normal and nothing to worry about.
Have you ever taken off your underwear and noticed a strange bleached patch directly online.

Surprisingly, these patches have nothing to do with your washing machine. Instead, they are caused by the natural pH levels of the v*gina.

These patches indicate a healthy vagina. pH levels measure the acidity or alkalinity of a substance, and as one informative Twitter post explains:
On a scale of 0-14, anything below 7 is acidic, and anything above 7 is alkaline. For everyone to know, it’s completely normal to discover lighter patches on a woman’s underwear and knickers due to the acidic nature of the vaginal discharge. The discharge is actually healthy, and it is the body’s way of preventing infections and maintaining a healthy pH balance. It’s a healthy vagina if one spot can bleach the fabric.

Dr. Vanessa Mackay of the Royal College of Obstetricians and Gynaecologists explains: “The vagina has a self-cleaning mechanism through natural secretions. The body produces discharge to maintain chemical balance and to protect the vagina.”

The natural pH level of the healthy vagina is quite acidic (typically in the range from 3.8 to 5.0), making it moderately acidic compared to the neutral pH level of 7.
Dr. Mackay also notes that clear or white vaginal discharge is normal and healthy, and that disrupting this natural balance can lead to infections.