At the end of the day, if women check their underwear and notice these 4 signs, it may indicate that can.cer is silently “gnawing away” at the body

Checking underwear is one of the simplest ways for women to detect gynecological problems early and identify the possible presence of malignant tumors in the ovaries, uterus, and other reproductive organs.

Underwear is often likened to a “mirror” reflecting reproductive health and the first “line of defense” protecting intimate areas. When malignant tumors develop in the ovaries, uterus, vagina, vulva, or even the anus and rectum, they can cause noticeable abnormalities on underwear.

If, at the end of the day, you notice any of the following four abnormalities, you should not be complacent, as they may be warning signs of cancer:

1. Abnormal bleeding not related to menstruation

This is the most dangerous “red flag” and must never be ignored. If you find fresh blood, pinkish-brown streaks, or rust-colored stains on your underwear outside of your normal menstrual cycle (abnormal bleeding), seek medical attention immediately. Such bleeding is often caused by tissue damage or bleeding from a tumor and is a leading symptom of cervical cancer, endometrial cancer, and vaginal cancer.

Cancer can damage surface tissues, making blood vessels fragile and prone to bleeding, with blood often seeping and collecting in the crotch area of underwear. In particular, any postmenopausal woman who notices blood on her underwear should undergo cancer screening immediately.

2. Yellow, green, or gray stains accompanied by a persistent foul odor

If, at the end of the day, you notice dark yellow, yellow-green, or gray stains on the crotch of your underwear (from dried abnormal discharge), along with a fishy or strong unpleasant odor that does not go away after personal hygiene, you should be cautious.

Although this may be due to a common infection, persistent foul-smelling stains with unusual colors can also be secondary signs of ovarian or uterine cancer. Tumors may cause blockages or secondary infections, leading to pathological discharge that becomes concentrated, discolored, and malodorous when it dries on fabric.

3. The crotch area becomes stiff, yellowed, and tears easily

If the crotch of your underwear becomes stiff, noticeably yellowed, and wears out or tears unusually quickly—not due to poor fabric quality—this can be an important indicator. When reproductive organs are damaged (possibly by tumors), they may produce abnormal vaginal discharge that is highly acidic and contains unusual substances.

When this discharge dries, it can stiffen the fabric, cause persistent yellow staining, and rapidly weaken the fibers, leading to premature wear and tearing of underwear within a short time (just a few weeks or 1–2 months). This rapid deterioration signals abnormal discharge associated with severe infection and the possible development of cancer.

4. Dark brown stains mixed with residue or digestive waste

This is a warning sign that a tumor has invaded surrounding tissues and formed fistulas—a dangerous condition requiring urgent medical attention. If you notice dark brown stains on your underwear, accompanied by a foul odor or residue resembling fecal matter, this suggests abnormal connections between organs.

The presence of digestive waste on underwear indicates that a malignant tumor (often colorectal cancer, rectal cancer, or advanced gynecological cancer) has formed a fistula connecting the intestines or rectum to the vagina. Rapid tumor growth and invasion of nearby tissues are the direct causes of such gastrointestinal fistulas.

Experts recommend changing and checking underwear daily to protect health and detect problems early. Do not leave underwear unwashed overnight, and avoid washing it together with socks or heavily soiled clothing. Replace underwear immediately if it becomes stiff, yellowed, moldy, or torn in the crotch area. Even if there is no visible damage, underwear should be replaced at least once every six months.