Vaginal yeast infection (Vulvovaginal candidiasis) in females is caused by an overgrowth of a fungus (candida albicans) that naturally lives in the vagina. Other factors include uncontrolled diabetes, weak immune system, pregnancy, hormonal imbalance, stress and lack of sleep and persistent use of antibiotics that decreases the amount of good bacteria (Lactobacillus) in the vagina. 

External genitalia usually appears swollen and red. Primary symptoms include vaginal swelling, itching, soreness, and redness, burning and during sex or urination and whitish-gray and clumpy vaginal discharge.

Common medications for simple infections includes antifungal creams, ointment, and vaginal suppositories, etc.