The microbiome is all the genetic information contained in every species of microscopic organisms that live in or on our body. More casually, all the bacteria and yeasts that live on our skin, in our mouth, in our gut, in the vagina, in the nasal cavity, and other places are thought of as our microbiota, or “flora”. In most healthy women, the vaginal microbiome is dominated by one of a few species of Lactobacillus: L. crispatus is thought of as the healthiest, with L. jensenii, L. gasseri also thought to be healthy, and L. iners having an uncertain status. Women whose microbiomes are dominated by L. iners or by non-Lactobacillus species tend to develop bacterial vaginosis (BV) more often than women with L. crispatus as their dominant species. Women with BV are more susceptible to other infections, such as herpes simplex virus (HSV) 2, human papilloma virus (HPV), human immunodeficiency virus (HIV), and perinatal infections. Pregnant women with BV are more likely to experience preterm labor/birth. In addition, a woman’s vaginal microbiome interacts with her body’s immune system in ways we are just beginning to understand.

Bacterial vaginosis – or BV for short – is a condition in which the healthiest bacterial species are no longer the dominant species in the vagina, and other bacteria grow in greater numbers. Symptoms of BV you may notice at home include having more vaginal discharge than usual, with a color that may vary from white to gray to light yellow. The discharge may have an unpleasant odor. You may experience vaginal irritation/burning or itching. Some women have no noticeable symptoms. BV is diagnosed clinically if 3 of the following 4 criteria are present: 1) Thin white homogeneous discharge 2) Clue cells present on wet mount microscopy (often not done in medical offices) 3) Vaginal fluid pH higher than 4.5 4) A positive “whiff test” – presence of an unpleasant, “fishy” odor when discharge on a microscope slide is combined with potassium hydroxide solution There are many reasons a woman may get BV. The bacteria associated with BV are just part of the environment – they may come from your own skin, from a sexual partner, from fecal material, or from products used in the genital area. BV may flare up because of menstruation, sexual activity, or using certain products in the vagina or vulva, or it may occur for no logical reason at all. Current medical guidelines call for treating BV with metronidazole or other antibiotics. These treatments are usually successful, but unfortunately, BV recurs within 6 months to a year more than half the time. Many women experience recurrent BV throughout their lives.

Boric acid is a chemical that is used as a laundry booster and a pesticide…and sometimes as a vaginal suppository. It is effective at killing yeast…and bacteria (including the good ones)…and just about everything it comes into contact with. The concept behind using boric acid to improve vaginal health is that it is an acid, and the vagina is acidic, so putting boric acid in the vagina should be good, right? Well, not so fast! First, it’s important to keep in mind that boric acid is toxic when ingested by mouth, so you have to be very careful to keep a boric acid product out of reach of children and pets and to wash your hands after using it. Second, not all acids are created equal. Every acid has a characteristic known as a pKa, which can be thought of as the pH level at which the acid switches and starts acting like a base. The lower the pKa, the stronger an acidifier it is – in other words, it’s better at making the fluid it’s in acidic. For example, lactic acid, the natural acidifier of the vagina, has a pKa of 3.86 – it’s a good acidifier, and is the reason vaginal fluid has a pH in the range of 3.5-4.1. In comparison, the pKa of boric acid is 9.2! This is much too high to be a good acidifier in the healthy pH range for a vagina. In fact, putting boric acid in the vagina is more likely to raise your vaginal pH, not lower it. Third, boric acid not only kills yeast, it kills bacteria. Killing off the beneficial Lactobacillus bacteria in your vagina creates a situation in which it’s easy for bad (pathogenic) bacteria to take hold and cause conditions like bacterial vaginosis (BV) or aerobic vaginitis (AV). So unless your own personal doctor is telling you to use boric acid for a very specific reason, you should avoid using it. Instead, for general vaginal health, look for products that contain lactic acid. Not only is it safer and more natural, it will be more effective at achieving a vaginal pH in the healthy range. Lactic acid alone will not kill yeast, but it will encourage a healthy vaginal environment that will help a healthy vaginal microbiome to flourish.