Tracking Cervical Mucus to Improve Your Chances of Conception (Episode 534)

Full Transcript: Episode 534

Lisa Hendrickson-Jack:

This is the Fertility Friday Podcast, episode number 534.

In today’s episode, we’re taking a deep dive into cervical mucus. I’m delving into a study that examined how effective cervical mucus tracking can be to optimize your chances of conception. So without further ado, let’s go ahead and jump right in.

All right, the study that we are going to be delving into today is called “Cervical Mucus Secretions on the Day of Intercourse: An Accurate Marker of Highly Fertile Days.” And like I said at the top of the episode, I’ll be linking the abstract to this episode so you can find it in the show notes page at fertilityfriday.com/451. And we’re just going to delve into what this study talks about.

To give you a general overview, basically what the researchers did is they took a group of 193 healthy Italian women who were trained in the Billings method of ovulation, or the Billings Ovulation Method. For those of you that are not familiar with a variety of different types of fertility awareness-based methods, the Billings Ovulation Method is a mucus-only method. And the way that the users of the Billings method are trained to observe and test mucus is a little bit different to the method that I teach. I’m trained in the Justisse method. I teach symptothermal. And I teach external wiping. And there’s a whole mucus classification system that I teach my clients and practitioners. But with the Billings method, it’s a little bit different, and it’s more based on observation and sensation. It’s not an external wiping method. But either way, you’re still very adequately trained to identify the various changes in cervical mucus and to identify the difference between different types so that you can identify days of fertility.

So it is useful just to keep in mind that the participants of the study, they are trained to look at their mucus in specific ways, and they are able to then distinguish between different types of mucus throughout the cycle quite reliably. Women were recruited into this study over a period of several years, and thousands of cycles were reported and recorded over the time of the study period.

To boil it down to what the researchers were looking to find, they were specifically wanting to study how effective tracking cervical mucus changes would be in terms of supporting women to conceive. So how effective identifying fertile quality mucus would be in helping women to identify their fertile window and improve their chances of conception. That’s essentially the point of the study. And so very relevant to us, because on the podcast, we’ve talked so much about mucus.

To give you the conclusion and the results right off the bat, and then we’ll delve into what it means in some of the nitty-gritty details — basically, what the researchers found was that when women were trained to rate their cervical mucus from basically dry to peak quality mucus, which is the clear, stretchy stuff, the probability of conception was highly correlated with the appearance of the most fertile quality cervical fluid. The probability of conception ranged from basically negligible for days with no noticeable mucus to about 30% for days with the most fertile type mucus detected by the women. So there was a direct correlation between the chances of conception and the woman identifying and then timing sex on days where she identified the fertile quality cervical mucus — the peak type mucus. In the language that I use and that I teach, we call that peak type mucus, the clear, stretchy, lubricative type cervical fluid.

So what does the study tell us? In the most basic terms, the study tells us that women can tell the difference between their cervical secretions, and that there’s a very high correlation between what we’re observing in our cervical mucus and what’s happening in our body around the time of ovulation.

What I always stress when talking about fertility awareness is that fertility awareness actually doesn’t help us to predict ovulation in the sense that we can’t ahead of time say, “Okay, I know definitely I’m going to ovulate on this day of the cycle.” That’s not the point of fertility awareness tracking. But what this whole observational routine does show us, tell us, and inform us about is at what point of the cycle are we fertile? At what point of the cycle can we conceive? So when we’re tracking cervical fluid, it’s telling us the fertile window. It’s telling us that these days are the days of fertility — these are the days where if you have sex, it’s possible to conceive, and these are the days that it’s not.

The bottom line is that women can be trained to identify their fertile window based on their cervical mucus. And so, to break it down a little bit, the women in the study were taught to rate their mucus on a scale of one to four. One was no sensation of cervical fluid or a dry sensation — basically no noticeable mucus. Two was they called it “slightly moist.” So there still wasn’t any noticeable or substantial mucus, but there was some sort of shift in terms of observation where it wasn’t completely dry, but there was a bit of a moist sensation.

Now, the Billings Ovulation Method is different to the wiping method. My understanding of the Billings method is that it’s more about sensation in the general sense — if you’re walking around throughout the day, you may pay attention to how you feel, if it feels wet as you’re walking around. It’s not necessarily based on observations in terms of wiping and looking. So when it says “no sensation,” it means that you walk around, you feel dry. When it says “slightly moist,” you feel a little bit moist.

Three on the scale of one to four was a damp sensation. The appearance described is creamy, whitish, yellowish, sticky, stringy mucus. Four is what I would refer to as peak mucus. It sounds like three would be more of a non-peak based on appearance, and four would be peak. Non-peak is more of the lotiony type, and then peak is more of the clear, stretchy, raw egg white type. It says wet, slippery sensation, clear stringy or stretchy fluid, watery mucus. And it also says blood trails.

So basically we have this very simple classification system where women are rating from nothing really there to this clear stretchy mucus and they’re basing their actions on that. In this research study, the women were tracking their cervical mucus every day. And they were tracking their intercourse. And so the researchers were then able to see when they were having sex based on what type of mucus they were having, and who conceived and when, and who was more likely to conceive based on what mucus observations they were having.

The women that were chosen for this research study were specifically chosen because they were not avoiding pregnancy. So the women who were part of the study were either actively trying to conceive or planning to conceive in the future — either way, they were not using contraception.

Unsurprisingly, the women who had sex on their days of peak mucus — the clear stretchy stuff — had the highest probability of conception. And the researchers talked a little bit about why that might be, which brings us into what this all means from a hormonal standpoint.

If we divide the cycle in half, we can have the pre-ovulatory phase — what happens before ovulation — and the post-ovulatory phase — what happens after ovulation. When we’re in the pre-ovulatory phase, approaching ovulation, we’re having a variety of follicles develop in the ovaries. One is inevitably chosen — that becomes the dominant follicle. And as this process is happening, as the egg is essentially being prepared for ovulation, the ovary is producing estrogen. It’s part of the developmental process of the follicle. So it is the estrogen that is being released that is triggering the cervix, the cervical crypts, to make cervical mucus.

When we’re tracking cervical mucus in a healthy normal cycle, what we’re actually seeing is a reflection of what’s happening hormonally. When we’re seeing that shift from basically dry, not really seeing anything, to starting to see some potentially lotiony type mucus, and going all the way up to the clear stretchy — as they classified it, a four on their scale — what we’re seeing is a reflection of the rising estrogen levels.

When you get closer to ovulation, the estrogen levels continue to rise until they hit a peak. And it’s that peak of estrogen that actually triggers ovulation. So it makes sense that when you’re seeing the highest quality of mucus — the peak type mucus — in the greatest quantities, that’s often correlating right very nicely with those high estrogen levels that happen right before ovulation.

Outside of the properties of mucus — which is a whole other rabbit hole, including how mucus changes the pH of the vagina, and keeps sperm alive, and filters out abnormal sperm, and all that great stuff that I talk about extensively in Chapter 3 of The Fifth Vital Sign — outside of the quality of the mucus to help fertility, it plays a key role in just straight timing. If you’re tracking your cycle and you’ve done it for a little while, you’ve started to notice patterns where you don’t really have a lot or you don’t have any, and then at a certain point of your cycle towards ovulation, that’s when you have the most and it’s most obvious. And so even just that very basic change that you see cycle after cycle — it’s related to that hormonal shift.

If you didn’t know anything else other than to have sex when you see that clear stretchy mucus, if you’re trying to conceive, that would significantly increase your chances of conception. One of the things that this study shows us is that the actual mucus itself is just as good — if not better — than a lot of the devices and various things that we use, including ovulation strips and apps with predictive settings. The mucus reliably outperforms those in women with healthy cycles according to the study.

A secondary and very important factor of cervical mucus is that it is associated with keeping sperm alive for up to five days and providing an ideal environment for sperm to thrive during that fertile window, so that the sperm is ready and waiting for when ovulation takes place. So two very important aspects of cervical fluid.

Essentially, the study confirms what many of us already know about cervical mucus. It highlights and gives us the scientific data to back up that cervical mucus is a reliable way to identify our fertile window, to help to time sex accordingly, because it is associated with the hormonal shifts that we’re seeing in the menstrual cycle. It also shows us that women can be taught to reliably understand, interpret, and identify the changes in their cervical mucus secretions. And although there’s always a learning curve to learning something new, there’s no evidence to suggest that women have a difficult time learning this basic information.

One other thing I thought was interesting is what the researchers said about cervical mucus and what they suggested in terms of its ability to help time sex effectively — and even potentially to time other procedures like IUI or other assisted reproductive technology. Basically, the researchers gave some clinical guidelines towards the end of the study. They said that in a clinical setting, when women are going for IUI, because the cervical mucus observations are so effective at identifying the most receptive time in the woman’s cycle — when women timed sex based on their cervical mucus in the highest category, a four on the scale, there was a significantly higher chance of conception compared to any other time of the cycle. So the researchers are actually suggesting that this could be a viable option for timing intrauterine insemination.

They said the advantages of this approach over ovulation detection kits include lower cost, and they noted that the most fertile type mucus symptoms typically begin early in the fertile interval and occur during the most fertile days, while ovulation detection kits typically miss the most fertile days.

The point they were making is that when you track mucus, you’re going to get mucus in a healthy typical cycle for several days before that strip turns positive. The ovulation predictor strips are testing for a hormone called luteinizing hormone, or LH. As you’re approaching ovulation, the estrogen is rising, and once that estrogen hits its peak, that sends the message back to the pituitary to release LH. LH triggers the ovary to release the egg — you get that positive LH test typically about 36 hours before ovulation. So you’re getting that about a day and a half before you actually ovulate. In a healthy typical cycle, you typically get cervical fluid for several days — maybe five or six days. So you’re getting more information, and earlier, from mucus than from a strip.

Another point the researchers made was that when you track the cervical mucus and all of the things that we’re tracking with fertility awareness charting, you’re getting additional information about ovarian function that could potentially help with diagnostics.

So basically, the study is telling us that not only is mucus an effective way of identifying the fertile window, but it is as effective if not more effective than the typical ways that we do that, including ovulation strips, and it should be considered a viable alternative.

To wrap up, when you’re tracking your cycle, whether you’re using sticky, creamy, egg white, and wet — or peak and non-peak — it falls into two categories: the lotiony stuff and the clear stretchy stuff. With just that basic knowledge from listening to today’s podcast, you have enough information to take a look at what’s going on and identify whether or not it’s that clear stretchy, and have sex on those days.

Peak mucus is associated with peak estrogen levels. What we’re seeing in terms of cervical mucus in a healthy cycle is in many ways a direct reflection of what’s happening hormonally.

Getting into some of the caveats — this study really did appear to study women who had pretty typical mucus patterns and were actually seeing cervical mucus on a cyclical basis. Not every woman sees that mucus reliably. Hormonal birth control is known to suppress mucus production. One of the main modes of action for hormonal contraceptives — whether it’s the pill, the patch, the ring, the shot, or the progestin-releasing IUD — is to suppress mucus production. So when you’re on hormonal birth control, your cervix is typically plugged with a thick mucus plug and you’re not making any clear stretchy cervical mucus.

Research has shown that over time, because you’re not making that mucus while on the pill, it can suppress and have a negative effect on your cervical crypts. So many women come off of birth control after being on for a long time — often two years or more in research studies, though I work with many women who’ve used it for ten, fifteen, or even twenty years — and find that they don’t necessarily have a whole lot of mucus. I’ve had clients who, for several months after coming off, see none at all, even if they’re ovulating.

There are also other situations — I’ve worked with many clients who’ve had cervical dysplasia and may have had a procedure done, whether it’s conization or LEEP, and it’s not uncommon for those women to have lower mucus production as a result. There are also certain medications — antihistamines, and even some fertility drugs like Clomid — that are known to suppress mucus production over time.

For women who are ovulating but not seeing mucus, it doesn’t mean they’re not fertile, and it doesn’t mean pregnancy is not possible. What it means is that mucus may not be the primary way to identify fertility in that case, because of impaired mucus production. For timing, the quantity isn’t necessarily what’s most important — what’s important is the shift in mucus. I’ve worked with many women who don’t necessarily have large quantities of clear stretchy mucus, but when they’re around that time of fertility, they do notice a shift or a change — whether it feels more lubricative, or there’s a sensation when wiping, or something in their underwear. Those are nuances, and if you’re having a difficult time, it’s a good idea to work with an instructor for a more personalized strategy.

Other strategies can include checking cervical position and using ovulation predictor strips as a second marker in addition to whatever mucus you’re seeing, so that you have two ways of identifying that window when ovulation is approaching.

Just a final note: because this study was tracking specifically for conception, if you are using fertility awareness to avoid pregnancy, you can flip this on its head. When you’re trying to avoid pregnancy, it’s crucial to avoid unprotected sex during that fertile window. Pregnancy is possible in any cycle with ovulation. Research tells us that there is a six-day fertile window ending in the day of ovulation. Whether you have strong mucus production or not, if you have unprotected sex during that six-day window, there is always a chance of pregnancy.

If I give a short recap: cervical mucus is a highly effective way to time sex when you’re trying to conceive, and research tells us it’s very, very effective and useful. Women are more than capable of being trained and taught to identify the differences in their cervical mucus and use that information accordingly.

I hope you enjoyed today’s episode. If you found it valuable and can think of someone who would benefit from it, the share link is fertilityfriday.com/534.