A yeast infection, or candidiasis, is a common fungal infection caused by an overgrowth of Candida albicans, a type of yeast naturally present in the body. This fungus typically resides in small, harmless amounts on the skin and in the mouth, gut, and genital areas. An infection occurs when the delicate balance of microorganisms is disrupted, allowing Candida to multiply excessively. The focus of this article is to clarify the relationship between this common condition and sexual activity.
The Nature of Candida and Transmission Risk
Yeast infections are not classified as traditional Sexually Transmitted Infections (STIs), such as chlamydia or gonorrhea, because they can develop in individuals who are not sexually active. However, this distinction does not mean the fungus cannot be transferred between partners during sexual contact. The act of sexual intercourse can facilitate the transfer of an existing microorganism from one partner to the other, leading to a new infection.
The transmission of Candida is considered a genuine risk, especially when one partner has an active infection. Approximately 15% of men who have unprotected intercourse with a partner experiencing a vaginal yeast infection will contract the fungus and develop symptoms.
When a yeast infection is continually passed back and forth between partners, it is referred to as the “ping-pong effect.” This cycle happens when one partner is treated and recovers, only to be reinfected by the other partner who is an asymptomatic carrier or has not completed treatment. Breaking this cycle often requires both partners to be evaluated and treated simultaneously, even if only one is showing symptoms.
Common Causes of Fungal Overgrowth
The majority of yeast infections are not acquired sexually but are instead endogenous, meaning they arise from an imbalance within the body. A significant non-sexual cause is the use of broad-spectrum antibiotics, which can indiscriminately kill the beneficial bacteria, such as Lactobacillus, that naturally keep Candida growth in check. This reduction in protective bacteria allows the yeast to overgrow, triggering an infection.
Changes in hormone levels also play a role in promoting fungal overgrowth. High estrogen levels, often seen during pregnancy or in individuals using high-dose oral contraceptives, can increase glycogen, a sugar source that Candida readily uses for growth. Conditions that compromise the immune system, such as uncontrolled diabetes or HIV, also make individuals more susceptible to recurrent or persistent infections.
Environmental factors can also contribute to the development of candidiasis. Wearing tight, non-breathable clothing, such as synthetic leggings, traps moisture and heat against the skin, creating a warm, damp environment where the fungus thrives. Maintaining proper hygiene and avoiding unnecessary moisture retention help the body maintain its natural microbial balance.
Recognizing Symptoms in Both Partners
Recognizing the symptoms of candidiasis is important for seeking prompt treatment and preventing transmission. For women, the infection typically presents with noticeable vulvar and vaginal itching and irritation. This is often accompanied by a thick, white vaginal discharge described as having a cottage cheese-like texture and generally lacking a strong odor.
Other common symptoms include a burning sensation, which can be particularly noticeable during urination or sexual intercourse. The genital area may also appear red and swollen due to inflammation. For men, a yeast infection may manifest as a red rash, itching, or burning on the head of the penis.
Men who contract the fungus are often asymptomatic carriers, meaning they harbor the Candida yeast without showing any outward signs of infection. This asymptomatic carriage is a significant factor in the potential for re-infection within a sexual partnership. Uncircumcised men and those with uncontrolled diabetes are at a higher risk of developing a symptomatic penile yeast infection.
Treatment Options and Prevention Strategies
Treating a yeast infection typically involves antifungal medications, which can be administered as over-the-counter creams, suppositories, or prescription oral tablets. Topical treatments are applied directly to the affected area, while a single-dose oral medication like fluconazole may also be prescribed for uncomplicated cases. It is important to complete the full course of treatment, even if symptoms improve quickly, to ensure the infection is fully cleared.
Prevention strategies focus on maintaining the body’s natural microbial balance and reducing the transfer risk. Managing underlying conditions, such as keeping blood sugar well-controlled in people with diabetes, is important for preventing recurrence. Avoiding the unnecessary use of broad-spectrum antibiotics can also help preserve the protective bacteria in the body.
During an active infection, it is generally advisable to abstain from sexual activity until symptoms have completely cleared to avoid discomfort and prevent the spread or re-infection. If sexual contact occurs while one partner is undergoing treatment, barrier methods, such as condoms, can reduce the risk of transmission. However, people should be aware that many topical antifungal creams are oil-based and can weaken latex condoms, making them less effective.