What causes bacterial vaginosis? And what can I do to prevent it?

It’s caused by an imbalance of good and bad bacteria in the vagina, which needs both but in the right proportions. You can get BV at any age, but the risk is higher once you hit menopause because estrogen and progesterone, which help maintain that balance, drop off. And that makes it easy for bad bacteria to multiply. It flies under the radar, but one in three women in the U.S. have had BV. 

Anything that disrupts the balance of bacteria can increase your risk.

The most common symptoms are a fishy odor and a thin white or yellow vaginal discharge, but there may be other symptoms, as well. The only way to know if you have it is to see a doctor, who, if you have it, will treat it with antibiotics (one study showed that adding probiotics to the course of treatment reduced recurrence). Left untreated, BV can increase your chances of getting pelvic inflammatory disease and sexually transmitted infections, like gonorrhea, chlamydia, herpes, or HIV.

Because anything that disrupts the balance of bacteria in your vagina can increase your risk of getting BV, preventing it may be a challenge. Antibiotics, sexual intercourse, douching, and smoking fall into that category. Some women just have the bad luck of having a naturally lower levels of good bacteria.

Don’t stop having sex (unless your doctor says to), and don’t stop taking prescribed antibiotics. Practice good vaginal hygiene. Use hypoallergenic, fragrance-free soap. Don’t use douche; the vagina is self-cleaning, and a douche disrupts the environment for good bacteria. Wear cotton underwear, which breathes. You can also try oral probiotics with Lactobacillus rhamnosus GR, which may reduce the chances that BV will recur.