You and your partner have just finished an awesome session of baby dancing during your fertile window. As you lie in each other’s arms in the calm after-glow, snuggled up together, you are probably not aware of the frenetic freeway of rush hour traffic going on deep inside your vagina, as your partner’s sperm jockey for position to reach the egg and father a child.
During ovulatory lovemaking, of the several hundred million sperm ejaculated into the vagina, only several hundred sperm will reach the Fallopian Tube, where only one sperm can fertilize the egg.
The selection and transport of sperm through the human cervix during the fertile time in a woman’s cycle is one of the greatest tales of physiologic change and adventure in the human body. This sperm journey is made possible by changes in the cervical mucus, which are triggered by an increase in the female hormone, estrogen, coming from the maturing egg before it is ovulated.
If cervical mucus or CM (also known as cervical fluid) doesn’t undergo very specific changes during ovulation, sperm will be stopped at the gate, so to speak, with NO chance of conception or pregnancy. To better understand just how important high quality fertile CM is to becoming pregnant, let’s look at how the quantity and consistency of cervical mucus changes as a woman moves through the phases of her menstrual cycle.
For most of the month, a woman’s CM is scant and thick. This CM acts to block sperm and harmful bacteria from ascending up the reproductive tract. This thick CM consists of long fibers that form a crisscrossed, dense network that make it difficult for sperm to penetrate. This makes sense, because most of the time, there is NO benefit to any outside cells being able to swim up inside our bodies. After intercourse during your non-fertile time, sperm are washed back out of the vagina or are gobbled up by white blood cells in the vagina. The vaginal ecosystem also helps sperm not proceed past “Go” by keeping things at an acidic pH (<5) that stops sperm motility (swimming).
But during the five days each month when ovulation is approaching, things change! As the egg matures, the follicle surrounding it secretes ever-increasing levels of estrogen. Estrogen causes the mucus fibers in the CM to rearrange to form nice straight pathways that allow sperm to travel quickly to reach the Fallopian Tube and the egg.
In addition to a change in actual structure and pathways, the amount of CM made during a woman’s fertile time dramatically increases. Fertile CM becomes “egg-white” cervical mucus (fondly known as EWCM). It is slippery and stretches between a woman’s fingers. Many women will notice this clear slippery EWCM on their underwear or on toilet paper, even if they don’t realize they are ovulating. Learning to track the presence of EWCM is one of the most reliable methods of identifying a woman’s fertile time. To learn more about the art of CM charting for optimizing or preventing pregnancy be sure to check out OvaGraph – the official fertility charting tool of Taking Charge of Your Fertility, Toni Weschler’s best-selling book about how to use key fertility signs to pinpoint ovulation.
When fertile quality (or egg-white) cervical mucus is present, sperm penetration through the cervix is maximized. As estrogen levels rise in the woman’s blood stream, calcium levels decrease and pH levels increase inside the vaginal canal. These changes create a safer, more protected environment for sperm. High calcium can trigger changes in sperm chemistry, which reduces sperm life-span, and an acidic environment reduces sperm motility. During ovulation, the woman’s body makes a healthy place for sperm by shifting the vaginal ecosystem to a low calcium environment with a neutral pH of 7 to 8.
These changes in calcium and pH also allow the mucus in the cervix to become more full of water and slippery, as the fiber pathways form. To make these straight sperm roads, cells lining the cervix produce mucin granules, which are little packets containing mucus. In the days immediately preceding ovulation, these secreted granules begin to swell within 10 seconds after their release, and they are totally dispersed into a nice slippery EWCM gel for sperm within 30 minutes. The water to hydrate these granules comes from the vaginal cells as they become more leaky also due to the woman’s increasing estrogen levels. Water dissolves these mucus granules, increasing the volume of CM 20 fold.
A multitude of other changes in CM also occur as ovulation approaches, including a switch from the production of acidic sugars to neutral pH sugars, again helping to maintain the optimal higher pH for sperm and CM hydration. And a pre-ovulatory decrease in CM fructose also occurs to modify sperm function in the vagina.
All of the changes in the quantity and consistency of CM that occur around the time of ovulation are critical for selecting and protecting the healthiest and strongest sperm to participate in fertilization. As sperm pass though CM, the sperm with the highest quality DNA (genetic material) are preferentially allowed through. And the woman’s body can help turbo charge sperm on their journey to the egg, with sperm reaching the Fallopian Tube within minutes from ejaculation.
Specifically, contact of sperm with cervical mucins causes a dose-related increase in the sperm swimming speed, which means that the more cervical mucus present the faster the sperm will swim. And contractions in the woman’s body also help move the sperm up quickly to meet the egg. In fact, within 45 minutes from intercourse most, if not all, the sperm that will participate in fertilization have reached the Fallopian Tube.
As wonderful for sperm as healthy EWCM is, not all women consistently produce the quality or quantity of fertile CM needed to optimize natural fertility. In fact, up to 20% of cases of suboptimal fertility in women may be due to disruptions in EWCM production. Hormonal regulation of CM production is greatly impacted by a woman’s estrogen levels. Estrogens create fertile CM by: increasing water flow through the vaginal cells for adequate hydration; decreasing vaginal calcium levels and elevating vaginal pH. All these changes are needed to allow the rapid mucin hydration needed to decrease CM thickness and to form the pathways the sperm need to move quickly through the female reproductive tract.
Poor CM production can be seen in women:
Increasing Production of Fertile Quality Cervical Mucus
A primary goal for improving EWCM production is stabilizing normal hormone production. This can be done through lifestyle changes and/or in collaboration with a healthcare provider. Other approaches can help as well.
1. Avoid vaginal products that can change EWCM production or create an unfriendly environment for sperm. Given that a woman’s body naturally LOWERS calcium and fructose in the vagina during ovulation, avoiding any vaginal products that contain calcium and fructose during your fertile window (the days leading up to ovulation) is recommended. Also avoid any lubricants or douches that lower vaginal pH.
2. Up to 75% of women report using Pre-Seed® to help improve quality or quantity of EWCM. Pre-Seed mimics the consistency of fertile-quality cervical mucus, and is at the correct pH for optimal sperm transport and CM mucin hydration. Unlike any of the other fertility lubricants on the market, PreSeed does not contain calcium or fructose that may interfere with EWCM production. It is also isotonic, with a physiologic balance of sodium and chloride, which other fertility lubricant products lack.
3. Find your ideal weight. Being underweight can strongly impact CM production and quality. If you are struggling with being over weight while trying to conceive, read my blog on finding 5 things you can do each day to start marching towards weight loss. Even just 5 pounds can make a difference!
4. Use supplements. I suggest taking Fairhaven Health’s FertileCM and FertilAid for Women together. These supplements are doctor-formulated, and made in the US in GMP-certified manufacturing facilities. I have recommended the Fairhaven Health brand of fertility supplements for over 10 years, as many women I have talked to report that these supplements helped improve their CM quality. Below is a list of just a few of the ingredients in these supplements that may help improve CM quality based on human and/or animal studies.
-Trace elements such as zinc, copper, iron, manganese, and selenium create the fluids that bathe and hydrate the CM mucin granules. Many people don’t consume enough trace elements in their daily diet. In animal model studies, it has been shown that animals that conceive easily have higher levels of trace elements in their cervical fluid than animals that take longer to conceive. As a previous large animal veterinarian, I kno wthat one of the leading causes of poor ovulation and abnormal cervical mucus quality in agricultural animals is trace mineral deficiencies, such as selenium, Vitamin E, Vitamin A and iodine. Supplementing animal diets with these elements can help farmers quickly improve fertility in their herds.
– Vitamin C plays a critical role in the rearranging of the CM fibers during ovulation. Without adequate Vitamin C, changes in CM around ovulation that create the sperm pathway can not adequately occur. Vitamin C in the blood stream has also been found to penetrate into cervical mucus where it can support sperm function and vaginal immunity.
-L-arginine increases nitric oxide synthase, which has been shown to improve cervical cell permeability and may increase CM hydration.
– Antioxidants that can protect sperm function. Men with low sperm quality often have very low levels of antioxidants in their semen. Antioxidant supplementation in the man has been shown to improve sperm quality. Antioxidant levels in cervical mucus reflect their levels in the woman’s blood stream. Supplementation of high quality antioxidants will increase CM antioxidant levels to support sperm function in the vagina.
Changes in cervical mucus structure and function are critical for normal fertility. Many women are unaware of the need to monitor and protect EWCM to optimize their chances of conception. All the good sperm in the world can’t lead a man to fatherhood if his sperm can’t find a path to reach the egg. The good news is that CM quality can often be improved by making knowledgeable choices to support your body’s unique changes during the fertile window.
Disclaimer: Please note that the information in this website is an educational resource. All decisions about any treatment you need must be made in consultation with your doctor or your healthcare provider who has examined you. Nothing in this post is meant to be used to diagnose or treat any person.
Other fertility articles:
- Irregular Periods Indicate that you are Ovulating Inconsistently
- Infertility Overview
- Predicting Ovulation and Fertility Charting
- Early Pregnancy Symptoms
- Fertility Health and Diet
- Antioxidants for Men: Optimizing His Swimmers
- A Needle in a Hay Stack…Finding Your Most Fertile Day
- FertilAid: A Rational Approach to Enhancing Fertility
- Beating Polycystic Ovary Syndrome with the Rule of 5
- Five Reasons Why It Is Cool To Freeze Your Sperm
- Cervical Mucus, Creating the Pathway to Fatherhood