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What your cervical mucus is trying to tell you about your fertility

What your cervical mucus is trying to tell you about your fertility

6 min read

What's up with the fluid that appears in your underwear sometimes? What is it? Why is it there? And why does it look different from time to time?

Your body produces many fluids that are perfectly normal, and cervical mucus, which shows up in various forms throughout your menstrual cycle, is one of them. You can track your cervical mucus to get to know your cycle, as well as identify when you're the most fertile.

Read on as we break down the basics of cervical mucus tracking. You'll learn:

  • What cervical mucus is
  • What cervical mucus has to do with your fertility
  • How to track your cervical mucus
  • What your cervical mucus looks like throughout your cycle
  • What can cause changes to your cervical mucus (and what to do about them)
  • Why social media is so worked up about cervical mucus (and women's bodies in general)

Cervical mucus 101

Cervical mucus is fluid secreted by your cervix. Most people can’t distinguish between the fluid naturally secreted by your cervix or vagina — and that discharge on your underwear is likely a combination of both cervical fluid and vaginal discharge. What it looks and feels like is dictated by your hormones — namely, estrogen and progesterone. This also explains why it changes throughout your cycle.

The hormone-powered cervical mucus transports sperm to the upper reproductive tract so it can meet up with an egg for fertilization. Because cervical mucus changes as it gears up for transportation time, tracking or monitoring the fluid is part of the fertility awareness method of natural family planning.

But tracking your cervical mucus is something you can also do to become aware of what your body is up to in general — regardless of whether or not you're trying to get pregnant. "If your aim is to get to know your menstrual cycle, tracking your cervical mucus is a physiological sign to follow," says Dr. Eva Luo, an OB-GYN at Beth Israel Deaconess Medical Center in Boston.

Cervical mucus and fertility

Your cervical mucus changes in amount, color, and consistency depending on where you are in your menstrual cycle. Tracking these changes can help you pinpoint ovulation and also help you identify your fertile window (the most fertile days: the five days before ovulation and the 24 hours after ovulation when unprotected sex gives you the best chances of getting pregnant).

A 2004 study found that changes in cervical mucus can predict the chance of conception as well as (or better than!) basal body temperature or urinary luteinizing hormone (LH) monitoring. The study showed that the probability of conception was highest on days when the most fertile type of cervical mucus was present.

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How do you know when you have the most fertile cervical mucus?

The changes in your cervical mucus are driven by fluctuations in your hormones. Before ovulation, estrogen is produced by the developing follicles (or egg sacs) in your ovaries, which then stimulates the production of cervical secretions. These secretions facilitate the passage of sperm. After ovulation, progesterone fuels the change in the secretions — which then prevents sperm migration and maturation.

Now that you know what’s happening behind the scenes, here’s what you’ll be looking for throughout your menstrual cycle if you’re thinking about cervical mucus monitoring or tracking:

  • At the beginning of your cycle, you get your period. As your period continues, any cervical mucus will likely be covered by the bleeding.
  • As your hormones amp up for ovulation, your cervical mucus will become more cloudy or sticky.
  • On the day you start ovulating, you'll have what's considered the most fertile cervical mucus, often referred to as "peak." The amount of fluid is different for everyone, but it’s slippery, clear, and stretchy — and resembles a raw egg white. If you want to get pregnant, you should have sex without birth control when you see this mucus.
  • After ovulation, mucus will likely disappear, since progesterone peaks during this time (in preparation for a potential pregnancy) and dries up your cervical mucus.

How does cervical mucus tracking work?

There are three methods of tracking your cervical mucus:

  • The Billings Ovulation Method: You check the texture and appearance of your mucus and chart it. If you’re using this method, you have to be super consistent so that you can really get to know what's happening. The Mayo Clinic suggests recording what your mucus looks and feels like for several cycles before deciding if you want to use cervical mucus tracking as a natural birth control method.
  • The Creighton Method: This method is similar to the Billings Ovulation Method — the only difference is that the Creighton Method requires you to score the secretions according to a multi-characteristic scale.
  • The 2-Day Method: In this method, you ask yourself two questions: Did I have cervical mucus today, and did I have it yesterday? If the answer is yes to either of these questions, you should use birth control if you’re having sex with a cisgender man and don't want to get pregnant. The 2-Day Method works best if you’re super tuned in to when you have cervical mucus.

How do you check your cervical mucus?

Once you decide which method you want to use to assess the state of your cervical mucus, there are a few ways to actually do it:

  1. Before you pee, wipe the opening of your vagina with white toilet paper or tissue, and then check the color and feel of the mucus.
  2. Look at the color and texture of the mucus on your underwear.
  3. Insert your (clean!) fingers into your vagina, and then examine the color and texture of the fluid.
  4. Place your fingers, with the fluid from your vagina on them, into a glass of water. If what you have on your fingers is cervical mucus, it will either stay on your fingers or sink to the bottom.

Tracking cervical mucus might sound like a lot of work, but studies conducted by the World Health Organization indicate that 93% of women can successfully identify and distinguish fertile and infertile cervical mucus.

That said, tracking your cervical mucus may be more challenging in the following situations:

  • Irregular or disrupted cycles: When cycles are irregular or disrupted by hormonal birth control; conditions like polycystic ovary syndrome (PCOS), Turner syndrome, or chronic cervicitis; or recent pregnancies; the amount and quality of cervical mucus can be impacted.
  • Dehydration: The amount of water in your mucus can increase or decrease its ability to penetrate sperm.
  • Persistent reproductive tract infections: Since cervical mucus and vaginal secretions are difficult to distinguish, changes to vaginal secretions as a result of infections will make tracking cervical mucus more difficult.  
  • Certain medications: Some medications — like Clomid, a fertility drug aimed at triggering ovulation — can change your cervical mucus. Likewise, if you have the Mirena IUD (a levonorgestrel IUD), it will thicken your cervical mucus to make it difficult for sperm to penetrate through (and therefore prevent pregnancy).  

Why are we so weird about cervical mucus?

If this article is the first time you're hearing about the ins and outs of cervical mucus, you're not alone. Fertility awareness methods aren't generally discussed in medical school — so unless you brought it up yourself, your doctor may not have mentioned it.

Even though some women (like comedian Jenny Slate) are trying to break the taboo of talking about bodily fluids, the stigma remains very much in tact. So much so that in April 2019, Instagram banned posts depicting cervical mucus because they “violate” the platform's policy on nudity and pornography. (Our jaws are dropping, too.)

What does a natural bodily fluid have to do with nudity or pornography? "It's all sexualized," says Dr. Luo. When anything having to do with women’s bodies is seen as sexual, it all becomes stigmatized — and, as a result, we end up lacking essential knowledge about how our bodies work.

"Unless you have a great OB-GYN you feel comfortable talking to, what you learn from your female relatives or friends — who were probably told to do things like douching (which we’ve since learned can be harmful) — becomes your practice," she explains. Her solution? Destigmatize women’s bodies by talking about what’s going on with them. And, she urges: "Use real words, not euphemisms."

At Modern Fertility, we're committed to providing you with the latest scientific knowledge about your fertility and your reproductive health (using actual medical terminology!). If you want to know what's up with your fertility hormones, our at-home test can start you on the right path with the information you need.

This article was medically reviewed by Dr. Eva Marie Luo, an OB-GYN at Beth Israel Deaconess Medical Center and a Health Policy and Management Fellow at Harvard Medical Faculty Physicians, the physicians organization affiliated with the Beth Israel-Lahey Health System.

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Chanel Dubofsky

Chanel's writing has appeared in Cosmo, Rewire, Lilith, HelloFlo, & Extra Crispy. She has an MFA in Fiction from Vermont College of Fine Arts & lives in New York. Follow her @chaneldubofsky.

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