Although thrush is not considered an STI, the infection can be transmitted during unprotected vaginal or anal sex, fingering, and oral sex
Although thrush is not considered a sexually transmitted infection (STI), the infection can be transmitted during unprotected vaginal or anal sex, fingering, and oral sex.
Thrush is typically caused by an overgrowth of the yeast Candida albicans, which lives on the skin, as well as in the mouth, intestines, and vagina.
According to some studies, sex can create an environment in which a fungal infection can grow, and sexual activity can exacerbate thrush symptoms.
How does thrush spread with sexual activity?
- Tiny cuts or tears: Women who develop thrush are more likely to have more Candida and microtraumas (tiny cuts or tears) on the vulva. Candida is normally present in small amounts on the skin, but approximately 20% of women are believed to have higher levels. If the vagina is dry or tight during sex, there is an increased risk of small tears on the vulva and vagina during penetration, which can cause Candida to overgrow. These tears allow candida to invade tissue and cause infection.
- Friction and hygiene: Sex can cause thrush due to friction that causes small tears around the vagina, especially if a woman has some vaginal dryness. Some studies claim that introducing foreign bacteria into the vagina via unclean fingers or the rectum can cause thrush, but there is no evidence to support this claim. However, it may increase the risk of other infections.
- Sex toys: Sex toys, especially when used without lubricants, can cause thrush if it causes irritation or microtears on the vulva as a result of friction or tightness. Because there is evidence linking sex toys and sharing sex toys to other STIs, it is recommended that sex toys be washed between uses and partners.
- Lube: Glycerin, a main ingredient in many types of lubes, has been proven to kill dominant bacterial species within the vaginal microbiome, which helps maintain an acidic pH. The vaginal environment is naturally slightly acidic, and if it becomes more alkaline, Candida can multiply.
- Douching: Douching can eliminate natural vaginal flora, allowing diseases to proliferate, and the practice has been associated with an increased risk of thrush, bacterial vaginosis, pelvic inflammatory disease, and other diseases. Douching before or after sex may increase the chances of developing thrush.
- Oral sex: Studies have found a link between responsive cunnilingus and the occurrence of thrush. This may be because oral sex introduces bacteria from the mouth to the vulva. However, the evidence is insufficient to establish a causal relationship between cunnilingus and thrush.
What causes thrush?
Thrush thrives in warm, damp environments and often occurs when there is an imbalance in bacteria. Causes and risk factors include:
- Hormonal changes caused by pregnancy or menopause
- Use of an intrauterine devices or spermicides
- Urinary tract infections (UTIs)
- Excessive use of antibiotics or steroids
- Uncontrolled diabetes, HIV, and other diseases that compromise immunity
- Products that may cause vaginal irritation
- Chemotherapy
- Tight-fitting or damp clothing
- Synthetic underwear
- Warm weather
- Stress
What are the signs and symptoms of thrush?
Thrush is more common in women, who can pass it on to their partners through sexual intercourse. Thrush may sometimes cause no symptoms, but if they do occur, they may include the following:
Symptoms of thrush in women
- Itching, soreness, and redness in the vicinity of the vulva, vagina, and anus
- Thick vaginal discharge (consistency of cottage cheese)
- Unpleasant vaginal odor
- Pain during urination or sex
- Vaginal edema and cracked skin surrounding the vaginal opening (severe cases)
Symptoms of thrush in men
- Irritation, burning, or itching beneath the foreskin or around the tip of the penis
- Redness of the genital skin or a splotchy rash on the penis head
- Discharge, discomfort, or soreness under the foreskin
- Unpleasant penis odor
- Pain when pulling back the foreskin
Thrush affects about 75% of women at some point in their lives, with some women experiencing it regularly. Thrush can spread to other parts of the body, including the armpits, groin, and between the fingers. This usually results in a red, itchy, or painful rash that may be scaly and have white or yellow discharge.
What are treatment options for thrush?
Treatment options for thrush may include one or a combination of the following:
- Antifungal cream
- Vaginal pessaries (pills that are inserted into the vagina)
- Oral antifungal tablets
Symptoms should resolve within 7-14 days. However, even if your symptoms go away sooner, follow your doctor’s instructions and complete the entire course of treatment. If the initial therapy fails, your doctor may recommend another test or a combination of treatments.
If your partner has thrush, you should avoid sex until they have finished treatment the infection has cleared up.