A yeast infection, or candidiasis, is a common fungal infection caused by an overgrowth of Candida species, most often Candida albicans. This fungus naturally resides on and within the human body, including the mouth, gastrointestinal tract, and genital areas. The infection occurs when the delicate balance of this internal flora is disrupted, allowing the fungus to multiply uncontrollably and cause uncomfortable symptoms. While commonly associated with women, yeast infections can also affect men. Understanding the distinction between a true infection and a trigger mechanism is important for understanding the link between this condition and sexual activity.
Understanding Transmission and Triggers
A yeast infection is generally not classified as a sexually transmitted infection (STI) because it is caused by an overgrowth of Candida already residing in the body’s natural microbiome. Unlike STIs, which require the transfer of a specific external pathogen, a yeast infection occurs when the existing Candida population flourishes due to an environmental shift.
Sexual activity often serves as a significant trigger mechanism by physically and chemically disturbing the natural environment of the genital area. The vagina maintains a naturally acidic pH (typically 3.8 to 4.5) that helps keep Candida growth in check. The introduction of semen, which is slightly alkaline, can temporarily raise the vaginal pH. This creates a less acidic and more hospitable environment for the fungus to overgrow.
Direct transfer of the Candida organism between partners is possible, though environmental triggering is more common. If a person has an active infection, they can transfer the fungus to their partner, potentially causing a subsequent infection if the recipient is susceptible. This partner-to-partner transfer is sometimes referred to as a “ping-pong” effect. Simultaneous treatment is often necessary to fully clear the condition in both partners.
Factors That Increase Risk During Intimacy
Factors related to sexual activity can heighten the risk of developing a yeast infection by disrupting the natural genital flora. Physical friction and irritation during intercourse can cause microscopic tears in the delicate genital tissues. This tissue damage makes the area more vulnerable to infection, providing an entry point for Candida to colonize.
The introduction of foreign substances is a major factor, particularly with the use of certain products designed to enhance intimacy. Many flavored or scented lubricants contain sugars, which serve as a direct food source for Candida, encouraging rapid overgrowth. Spermicides, often found in condoms or gels, also increase risk. They contain chemicals that can kill the beneficial Lactobacilli bacteria responsible for maintaining the vagina’s protective acidic environment.
Oral-genital contact presents a unique pathway for disruption, as Candida is a normal resident of the mouth and throat in many healthy adults. Receiving oral sex can transfer these oral Candida strains into the genital area, introducing a high concentration of the fungus. Enzymes present in saliva can also disrupt the established microbial balance, favoring fungal growth.
Factors not directly related to the sexual act can also make a person more vulnerable to infection afterward. Recent or ongoing use of broad-spectrum antibiotics kills off both harmful and beneficial bacteria, including the protective Lactobacilli that regulate Candida levels. Engaging in sexual activity while the genital flora is compromised significantly increases the likelihood of infection. Hormonal contraceptives may also increase susceptibility by altering the hormonal balance, making the environment more conducive to yeast proliferation.
Identifying an Infection and Next Steps
Recognizing the symptoms of a yeast infection is the first step toward seeking appropriate care, though symptoms can sometimes mimic those of other conditions, including STIs. For women, classic signs of a vaginal yeast infection include intense itching and a burning sensation around the vulva and vagina. This is typically accompanied by a thick, white, odorless discharge described as having a texture similar to cottage cheese.
Men can also develop a yeast infection, often presenting as balanitis, which is inflammation of the head of the penis. Male symptoms include redness, irritation, or a blotchy rash on the glans penis, sometimes with white, shiny patches. A white, lumpy discharge may also be present under the foreskin, especially in uncircumcised men, who are at a higher risk.
It is important to seek professional medical advice if symptoms appear for the first time, if they are severe, or if the infection is recurrent (four or more episodes within a year). Consulting a healthcare provider is necessary if there is uncertainty regarding the cause, as a proper diagnosis is required to rule out other infections. Simple hygiene practices can help reduce the risk of recurrence, such as gently cleansing the genital area after intimacy and thoroughly cleaning sex toys between uses.