What is cervical mucus and how to check it to get pregnant/fertile window/trying to conceive

You’ve heard a lot about cervical mucus along your journey to conceive, and that’s for good reason.

Cervical mucus, a fluid released by glands in your cervix, plays a fundamental role in conception. It safeguards and nourishes sperm as it swims to its ultimate destination: your egg. Increasing your knowledge about this critical fluid helps you to time sex better — and become pregnant.

Here, we delve into the role of egg white cervical mucus and irregular cervical mucus to help you pinpoint the days you have the best chance to conceive. We also look at possible ties between cervical mucus and unexplained infertility.

How does cervical mucus help sperm?

The vagina is naturally acidic, with a pH balance designed to ward off microorganisms and infection. Vaginal acidity is a good thing — except when it comes to sperm. Vaginal acidity can kill sperm, which need an alkaline environment to thrive.

Fertile cervical fluid makes the vagina hospitable to sperm. Fertile cervical mucus, often described as egg white cervical mucus, is alkaline. Because sperm are also alkaline, fertile cervical mucus provides sperm with safe passage on the long journey to the egg. Sperm may live 3-5 days in fertile mucus — but can die within minutes to hours in hostile mucus.(1)

Fertile cervical mucus also nourishes sperm, while creating an ideal aqueous channel to the fallopian tubes. The crystalline structure of fertile cervical mucus allow sperm to swim with the least effort, and in the right direction, to reach the egg.(2) At the same time, cervical mucus acts as a filter, excluding sperm with defects.(3)

What is fertile cervical mucus?

In the days leading to ovulation, the level of the hormone estrogen surges. In response, cervical mucus becomes thin, clear or white, and slippery — like an egg white. This consistency is a signal of fertile cervical mucus.

When is the fertile window for cervical mucus?

The age-old notion that ovulation occurs like clockwork on day 14 is outdated. Everybody’s menstrual cycle is unique. In fact, one study found 30 percent of women didn’t ovulate on day 14 of their cycle.(4)

That’s why it’s important to familiarize yourself with your own cycle by monitoring your cervical mucus over several months. That said, the timeline below may serve as a useful yardstick: (5)

• Days 1–5: Early in the cycle, when menstruation occurs. Your vaginal pH may become more acidic beginning around day 2-14 of your cycle.(6)
• Days 5–10: Typically you’ll notice little to no cervical mucus after your period. In the following days, you may see a sticky fluid.
• Days 10–14: As your body starts to produce more estrogen, the glue-like mucus may thin out and appear cloudy. As days pass, the mucus grows slippery and begins to look like egg whites.
• Day 14: For many, cervical fluid on the day of ovulation is very wet and ropy. You may be able to stretch the cervical mucus an inch or more between your fingers.
• Days 14–22: A surge of the hormone progesterone after ovulation dries up cervical mucus. Your mucus may look cloudy initially, then become thicker.
• Days 22–28: Your mucus may have a glue-like consistency again as your period approaches. You’ll typically see little or no discharge 1–2 days before your period.

Again, these changes depend on your individual cycle. If you ovulate early or late, your cervical mucus may not follow this timeline. You may have more dry days, or more wet days. Everybody is different. Life events also may make cervical mucus irregular.

What if my cervical mucus is irregular?

It’s normal for cervical mucus to change in response to common life events. Stress, significant weight gain or loss, long-distance travel, strenuous physical activity, and illness are among the factors that affect your hormones, along with your cervical mucus.

Changes in your cycle, including to your cervical mucus, also may be caused by hormonal disorders like hypothyroidism or hyperthyroidism, or polycystic ovarian syndrome.(7)

Does irregular cervical mucus cause unexplained infertility?

Abnormalities with cervical mucus may play a role in unexplained infertility, which one estimate suggests affects 20-30 percent of couples.(8) Although an average of 200-300 million sperm may be released during ejaculation, only a few hundred come close to reaching the egg.

One paper theorizes that unexplained infertility may be partly explained by hostile cervical mucus. However, the paper doesn’t suggest that certain types of cervical mucus are the sole cause of unexplained infertility.

Still, factors that alter cervical mucus to make it inhospitable to sperm include:

• Chronic cervicitis
• Sexually transmitted infections
• Cystic fibrosis
• Fertility drugs like Clomid
• The blood pressure drug propranolol
• Nicotine use

How do I check my cervical mucus?

There are three common ways to monitor your cervical mucus:

• Before urinating, wipe the opening of your vagina with white toilet paper. Check the color and feel of the cervical mucus.
• Put clean fingers into your vagina. Check the texture and color of the cervical mucus on your fingers.
• Feel the texture of the cervical mucus on your underwear.

Rubbing and pulling the cervical mucus between your thumb and index finger is the ideal way to evaluate its consistency. You’ll want to record everything you notice, including whether the fluid is dry, sticky, wet, cloudy, or slippery.

When it comes to cervical mucus patterns, knowledge is power. Getting to know your own cycle is yet another guidepost on your journey to become pregnant.

1. https://nfp.marquette.edu/reproduction.php

2. https://www.kindara.com/blog/cervical-fluid-and-fertility

3. https://www.bioscience.org/2013/v5s/af/S386/fulltext.htm

4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC27529/

5. https://www.plannedparenthood.org/learn/birth-control/fertility-awareness/whats-cervical-mucus-method-fams

6. https://annals.org/aim/article-abstract/695693/vaginal-physiology-during-menstruation

7. https://billings.life/en/safeguard-reproductive-health/pcos-other-hormonal-disorders.html

8. https://www.researchgate.net/publication/277614106_Insights_into_the_role_of_cervical_mucus_and_vaginal_pH_in_unexplained_infertility