In healthy women, mild vaginal itching or odor is normal and should not cause concern. If you develop persistent or excessive vaginal symptoms, you could have an infection. Schedule an appointment with your gynecologist to determine the cause of your vaginal itching and foul odor symptoms.

There are a number of healthy bacteria that help maintain the normal acidic environment within the vagina. If the levels of a protective bacterium--called lactobacilli--decrease abnormally within the vagina, you can develop a vaginal infection called bacterial vaginosis. Symptoms of this infection include vaginal itching and a foul, fishy odor, which can be exacerbated by sexual intercourse or your menstrual period. You may also experience excess vaginal discharge that is white or gray, explains The Merck Manuals: Home Edition, a medical encyclopedia for caregivers and patients. Treatment of bacterial vaginosis typically involves antibiotics that are administered vaginally or orally.

Women who develop trichomoniasis, a sexually transmitted disease, can experience symptoms of vaginal itching and foul odor due to this infection. This condition is caused by the presence of a parasite called Trichomonas vaginalis within the vagina. If you have trichomoniasis, you can experience vaginal itching or irritation and may develop abnormal vaginal discharge that is yellowish in color and has a strong, foul odor. Additional symptoms associated with this condition include lower abdominal pain or discomfort during urination or sexual intercourse, warn health officials at the Centers for Disease Control and Prevention. Your doctor may prescribe antibiotic medication to help resolve symptoms associated with this infection.

A vaginal yeast infection occurs due to the overgrowth of Candida albicans--a naturally occurring fungus that resides within the vagina, mouth and digestive tract. Symptoms of a vaginal yeast infection include severe vaginal itching and a foul, yeasty odor. Women with this condition typically also develop abnormal vaginal discharge that is thick, white or cottage cheese-like in consistency. Additional vaginal yeast infection symptoms can include swelling of the vulva or pain during sexual intercourse. This infection is typically resolved through the administration of antifungal vaginal creams or suppositories, explain health professionals at Medline Plus, an informational health website established by the National Institutes of Health.