Yeast, also known as candida, exists in everyone's bodies. While normal amounts do not typically cause problems, excessive amounts can lead to an infection known as candidiasis. Certain medications may cause this excess yeast. According to the University of Maryland Medical Center (UMMC), approximately 75 percent of women will develop vaginal yeast infections at some point, and roughly 90 percent of people with AIDS acquire candida-related infections.
Pregnancy
Hormonal shifts and increased sugar in vaginal secretions that occur during pregnancy may contribute to candida overgrowth. As a result, women's chance of developing yeast infections during pregnancy are greater than any other time, according to the American Pregnancy Association. Yeast infections may recur throughout pregnancy; however, they are not believed to have a negative impact on the mother's or infant's health.
Excess Body Weight
Excess body weight can foster yeast overgrowth. In general, the more added weight people carry, the more likely they are to develop excessive amounts of yeast. According to research published in the "American Family Physician" in September 2005, obese individuals are prone to infections in the skin-folds created by excess body weight. The area within the folds tends to remain warm and moist--two factors that can trigger yeast production. As a result, fungus comprised of yeast develops and frequently leads to candidiasis. When the skin folds become inflamed--a condition known as intertrigo, the chance of additional yeast and infection increases further.
Medications
Numerous medications may also trigger yeast overgrowth. According to the UMMC, antibiotics, certain birth control pills and corticosteroids--steroid hormones--are common culprits. Antibiotics reduce healthy bacteria in the body, which can make way for fungus and infections. Similar to pregnancy, hormonal changes brought on by birth control pills may increase yeast production. Corticosteroids may affect hormones and yeast-growth similarly.
HIV/AIDS
Since HIV/AIDS dampens immune system strength, yeast overgrowth and infections are common. According to the Mayo Clinic, people with HIV/AIDS may develop candida esophagitis, which causes swelling and a creamy white coating in the esophagus. Vaginal yeast infections and thrush--yeast overgrowth that develops on the tongue--may also develop. Children with HIV/AIDS may experience the most severe and bothersome yeast-related symptoms.
