You’ve got an itchy, irritated vagina. It must be a yeast infection, right? Not so fast. With that specific type of discomfort, you may actually be dealing with an even more common condition, says Maren Rae Oser, CNM, WHNP, RN, a certified nurse midwife based in Philadelphia. “When women come to me with vaginal irritation, many of the cases end up being bacterial vaginosis (BV) rather than a yeast infection.”
In fact, about 30% of women ages 14 to 49 will have BV at some point, according to the Centers for Disease Control and Prevention. “It’s important that more women understand what it is, why it happens, and what to do about it,” says Oser.
What exactly is BV?
Just like the proper balance of bacteria in your gut keeps you healthy, the same is true for your vagina. You want the good bacteria to keep the not-so-good bugs in check, says Oser. “When the number of good bacteria goes down, it leads to an overgrowth of the bad kind, and you can end up with BV.”
BV also messes with the natural pH of your vagina, adds Oser, which can lead to more problems. “The good bacteria help keep your vagina at a low pH, which discourages other bacteria, yeast, and viruses from thriving,” she says. When BV throws off that pH level, your protective vaginal mucus doesn’t work as well, leaving you more vulnerable to sexually transmitted infections.
“BV is also particularly bad for pregnant women,” adds Mary Jane Minkin, MD, an OB/GYN and clinical professor of obstetrics, gynecology, and reproductive sciences at Yale Medical School. “It can actually travel up to the uterus and set you up for preterm labor.”
Signs of a BV infection
Considering the problems that BV can cause, it’s important to recognize the symptoms. Call your health care provider if you’re experiencing any of these:
- A fishy odor that’s especially strong after sex
- Pain, itching, or burning in or around the vagina
- A thin white or gray discharge
- A burning sensation when you urinate
Most women with BV will have a smelly discharge and vaginal irritation, Dr. Minkin says. “Many will also tell me that they used an over-the-counter medication for a yeast infection, but it didn’t help,” she says. If BV is suspected, the first step is to test a sample of your discharge.
“We look for a thin discharge, a whitish-gray color, a pH greater than 4.5, a fishy smell, and BV cells visible under a microscope,” Oser says. “We typically need to see at least 3 of these criteria to diagnose BV.”
Why BV happens
Experts don’t know exactly what causes BV, but several things can disturb your vaginal ecosystem and make it more likely.
New relationships top that list, says Maureen Whelihan, MD, a gynecologist in Palm Beach County, Florida, and a spokesperson for the American College of Obstetricians and Gynecologists. “Sex with someone new, as well as having multiple partners, can contribute to women getting BV,” she says. “And it’s even more likely if you’re not using condoms.”
Poor hygiene habits are another issue, adds Dr. Whelihan. “It’s absolutely essential to wipe from front to back after you use the bathroom,” she says. Rinsing out the vagina with liquid (douching) can also invite problems because it can upset your natural bacterial balance.
Finally, if you have a sexually transmitted infection, you’re more likely to get BV, says Oser. Research in the Journal of Infectious Diseases shows that people with genital herpes are 55% more likely to get BV. Chlamydia, gonorrhea, trichomoniasis and HIV also increase the chance of getting BV, according to other research.