Candida & BV Info

The Unlikely Causes of Yeast Infections: What Your Doc Didn’t Tell You

So, doctors will tell you usually that causes of yeast infections include:

  • Hanging out in sweaty gym clothes/wet swimwear
  • Eating a lot of sugar
  • Douching
  • Recent antibiotic use

If you’re like me and get yeast infections all the time, hearing this is SUPER FRUSTRATING…because you probably know not to do any of these things.

So what else can cause yeast infections? The stuff that people don’t talk about as much?

Really anything that causes a potential disruption in vaginal pH or hormones.

*NOTE: this is true for BV as well, but a discussion for another time. Wondering what the difference is between BV and yeast infections? You can find out here.

Vaginal pH

So elevated pH causes a perfect environment for candida to thrive. And candida is a pernicious sucker…once it takes hold, it keeps going…. driving your vaginal pH higher and higher. What you want is for your vagina to be slightly acidic (4-4.5 pH)….literally a sour puss (sorry I’m not sorry for that one). But there are a lot of things that disrupt this delicate balance, wipe out the precious Lactobacilli bacteria which promote even-keeled pH, and wreak havoc on your vagina.


Yeast infections happen (and thrive) when you have elevated estrogen levels. A study carried out on mice actually showed that when they were exposed to increased levels of estrogen, it created severe and persistent yeast infections. Eek! The logic goes that estrogen deposits glycogen (a form of sugar) into the vagina, feeing the yeast already living in the vagina.

Remember how some yeast is OK, and how it’s the OVERGROWTH that is problematic? It’s like how 1 cookie is OK, but 100 cookies will probably make you sick. The danger of too much of a good thing…

What’s interesting, is that the counterpart to estrogen, progesterone, may have the opposite effect. Studies indicate that progesterone may actually help PROTECT you against yeast infections, by reducing the ability of the yeast to form biofilms and invade the vagina (as demonstrated in this study).

Like, for example, *drumroll please*….

1. The birth control pill

MAN. So much I could say about the birth control pill. I know it works well for a lot of women who seem to have 0 issue with it… but it’s what opened Pandora’s box for me and set me on this whole journey. And from the perusing around the Internet I’ve done, I’ve found endless personal accounts of people’s lives being WRECKED by the pill (candida related and not). How it relates here is that candida can attach itself to estrogen. As a result, your body doesn’t use the estrogen, driving overall estrogen levels down…. leading to a corresponding increase in progesterone. AKA the perfect environment for candida to flourish! Yeast infection, here we come.

2. Sex

This has to do with a few different things.

  1. The very act of sex raises your vaginal pH

That’s right. To prepare for a possible semen delivery, your vagina actually increases in pH (whether or not said delivery actually happens!). The vagina is normally acidic, and becomes more alkaline to protect sperm on the way to their egg.

2. Your partner’s bodily fluids affect your vaginal pH

The fact that bodily fluids (both yours and your partners) mess with vaginal pH. It’s why you see more instances of BV/yeast infections in female-female partnerships, because the different pHs of the vaginal fluid involved impact each other. And remember, the vagina is a very DELICATE! There’s just more extended fluid exchange in general, vs. in male-female couplings, there’s only 1 real moment of male -> female fluid exchange… and yeah, semen definitely does disrupt vaginal pH. Plus, semen is alkaline, which also contributes to that elevated pH that we talked about earlier. Yeck.

3. Your partner’s bodily fluids can create a warm, wet vaginal environment — perfect conditions for yeast to thrive!

And if the guy ejaculates inside of you… well, hello, warm, wet environment (AKA the perfect breeding conditions for yeast).

3. Your menstrual cycle

Not just those fateful 5 days (or however long yours is) — but the hormonal changes during different parts of your cycle have some serious implications for your vagina. There are 2 specific weeks that you’re most susceptible to yeast infections: 1) the week leading up to and including ovulation and 2) the week right before your period.

Why does this happen?

Well, during that first week before ovulation, your estrogen levels are higher, which creates an environment conducive to candida growth.

And in the week before your period, estrogen dips significantly, altering vaginal pH. That creates an environment that makes it tough for the good bacteria to survive.

Too much, too little of a good thing… all problematic. Your reproductive system is like freaking Goldilocks. Annoying, I know.

That being said, it’s not all doom and gloom — there’s good news here.

1st thing is that you’re actually LESS prone to yeast infections right after ovulation, due to rising progesterone levels. Hooray!

Secondly, if you are part of that fateful camp that gets yeast infections right before your period (yep, that’s me, too)… the good news is that they typically clear up once your period is in full flow. That’s right — menstrual blood actually raises the overall vaginal pH, which creates an inhospitable environment for yeast to grow.

However! Big However here! A big thing to be wary of here are tampons — they actually alter your vaginal pH, which can mess things up. And pads aren’t much better… they don’t particularly allow for air flow, which again, creates an IDEAL yeast-growing environment. So what’re you left with? Well, menstrual cups. But that’s a story for a different post…