Flo Fact-Checking Standards

Every piece of content at Flo Health adheres to the highest editorial standards for language, style, and medical accuracy. To learn what we do to deliver the best health and lifestyle insights to you, check out our content review principles.

What is cervical mucus? And why is it important?

Cervical mucus isn’t talked about much, but it plays an important role in your cycle, especially if you’re trying to conceive. Here’s what you need to know

Pregnancy test

Most women and people who menstruate have vaginal discharge, but did you know that cervical mucus, also known as cervical fluid, is integral to your cycle?  

Initially, it might not seem that important to get into the nitty gritty of discharge, but if you’re trying for a baby it’s important to understand cervical mucus because it can often reveal when you’re ovulating and therefore at your most fertile

Even if you’re not currently trying to conceive, getting to know what’s happening inside your body can be very empowering. 

Every one of us is different when it comes to the type, amount, and texture of discharge and cervical fluid we produce, so knowing what’s healthy for you and your cycle can be reassuring. You’ll also be more in tune to look for changes in your discharge (maybe color or smell) that could signal something’s not quite right down there. 

That said, cervical mucus isn’t something you learn about at school, so you can be forgiven for not knowing much about it. Our guide will help you get up to speed fast.

Take a quiz

Find out what you can do with our Health Assistant

What is cervical mucus? Is it the same as discharge?

First up, a bit of a biology lesson. 

Vaginal discharge is a catchall term for everything your vagina produces, throughout your cycle. You might notice that the amount, texture, and color of your discharge (from clear to milky white) changes throughout the month. This is completely normal. After all, discharge’s function is to keep your vagina safe by removing dead cells and bacteria.

Think of cervical mucus as just one ingredient that makes up your discharge. As its name suggests, this fluid comes from the glands in and around the cervix, rather than the vagina itself — but it has an equally important role to play. 

The cervix is a small-but-mighty, donut-shaped part of your reproductive system (read more about it here). Usually around an inch long, it joins the top of your vagina to the lower part of your uterus, moving up and down during your cycle. Experts think this could be a tactical move to help the blood leave your vagina during your period.

The cervix’s main job, however, is to produce clear or white mucus that not only safeguards the uterus, ovaries, and uterine tubes (basically all the important reproductive organs) from infection but also protects healthy sperm as they travel through the tubes in the hope of fertilizing an egg. Clever, eh? 

Different types of cervical mucus

During each cycle, the body works around the clock to prepare for a potential pregnancy. This means the brain and different parts of your reproductive system (think the ovaries, cervix, etc.) are constantly talking to each other to make sure everything is working properly.

Cervical mucus production is mainly controlled by the hormone estrogen, which is also behind some of the other cycle changes you experience. 

Let’s run through why your discharge might look and feel different from day to day (including the amount of that all important cervical mucus), and deep dive into why.

The menstrual cycle is broken down into three stages: follicular, ovulation, and luteal. Each one impacts your hormone levels differently, which has a direct impact on the color, texture, and amount of discharge and mucus your body produces.  

Day one of your period (and your cycle) is when the hormones estrogen and progesterone are at their lowest. 

While your uterus is busy shedding its lining (AKA your period), these hormones will slowly start rising again, so you’ll probably feel less tired. During the follicular phase, estrogen and progesterone are joined by follicle stimulating hormone (FSH), which is made in the pituitary gland. As its name suggests, FSH stimulates the follicles in the ovaries to mature in the hope of releasing an egg.

Immediately after your period, you’ll typically have “dry days,” when very little discharge is produced, and it’s barely visible on your underwear. 

After this stage, you’ll probably notice more mucus when you wipe. This discharge might be slightly red, yellowish, or pearly white in color and have a cloudy or sticky appearance. Your body is now preparing itself for the ovulation phase.

Cervical mucus

Fertile cervical mucus: What does it look like?

As ovulation approaches (your fertile window when the ovaries are most likely to release an egg, usually mid-cycle, although it can change month-to-month), you’ll no doubt spot another change in your discharge. Usually, we produce more mucus at this point, thanks to high estrogen levels. This is also when discharge tends to become clear and stretchy, similar to raw egg whites. The mucus is this texture to help the healthy sperm along on their way to the egg.

In addition to these cervical mucus changes, high estrogen levels also trigger the body to produce luteinizing hormone (LH). When it peaks, LH sends a message to the dominant follicle in the ovary to release an egg. That’s when ovulation happens. You might also notice that you’re more in the mood for sex around this time, thanks to the hormone testosterone.

After ovulation, the amount of discharge decreases, gets sticky again, and loses its stretchiness in the days leading up to your period. Estrogen levels are dropping off again, and progesterone is taking charge to thicken the uterine lining. If a fertilized egg doesn’t implant into the lining, your period will start in a few days.

How to check cervical mucus for fertility

Now that we know that the glands in our cervix produce the most mucus during our fertile window, tracking discharge changes makes sense if you’re trying to get pregnant. 

Why? Well these changes could help you work out when you’re likely to ovulate and, therefore, when the best time to have sex is. In fact, a 2013 University of North Carolina study of 331 women who were trying to conceive found that those who consistently monitored their cervical mucus were significantly more likely to get pregnant than those who didn’t.

That means looking at and touching your discharge, which you might feel a touch squeamish about, but remember — it’s all just liquid from your own body.

For some people, the changes may not be as obvious as described, and this is also perfectly normal. If it’s not as obvious at first, monitoring your discharge over a few months could help you start to see the changes.

An ovulation tracking app like Flo can help take the guesswork out of trying to conceive. You can log changes in your discharge then, using AI, Flo will help you figure out when your fertile window is likely to fall during your cycle.

Single image

Things that can affect cervical mucus

Certain medications, health conditions, and hygiene products can have an impact on the cervical mucus your body produces. These include but are not limited to:

  • Prescribed estrogen medications that help with fertility or treat conditions, like thin endometrium, can increase the amount of mucus you produce.
  • Contraceptives that prevent ovulation, for example the hormonal IUD and combined oral contraceptive pills, change your cervical mucus, so you won’t notice egg-white discharge around the middle of your cycle while using them.
  • Other forms of non-hormonal birth control, like the copper IUD, cause the cervix to make more mucus — something you’ll likely notice on your underwear in the months after you’ve had one inserted.
  • Being overweight might affect your cycle because fat cells increase the amount of estrogen (and therefore mucus) your body produces throughout your cycle.
  • An underlying sexually transmitted infection (STI) can impact the quality of your cervical mucus and, in some cases, cause a change in the color and smell of your discharge. Read more about STI testing here.
  • Vaginal conditions like bacterial vaginosis (BV) and yeast infections (also known as thrush) can cause a change in the color, smell, and quality of your mucus. For example, people with BV might notice that their discharge has a fishy smell. Find out more about what your discharge might be trying to tell you here.  
  • Some endocrine disorders, such as polycystic ovary syndrome, or PCOS, (a condition that affects the ovaries), can change the levels of estrogen in your body so you produce more cervical mucus on more days of your cycle.

If you’re concerned about changes to your cervical mucus or vaginal discharge, speak to your health care provider. They’ll be able to advise you on any medication-related questions, give you the information you need, and run some tests if necessary. 

Cervical mucus – the takeaway

We know now that cervical mucus comes from the glands in and around your cervix and plays a vital role in conception by helping healthy sperm safely travel through the cervix into the uterus to fertilize a waiting egg.

Cervical mucus is slightly different for everyone, but keeping track of changes in the color, texture, and amount of mucus in your discharge can help indicate when you’re most fertile.

Choose your Flo