Tracking Your Menstrual Cycle to Uncover Your Fertility
Updated: Jun 19
Ladies, your menstrual cycle can tell you volumes about your fertility if you know what to look for. Whether you're trying to conceive or avoiding pregnancy right now, here are the basic signs I want all of my female patients to know about.
Cervical fluid (aka cervical mucus) is secreted from glands in and around the cervix. It varies in consistency throughout the menstrual cycle. Around ovulation, this mucus thins out and becomes wet and stretchy thanks to increased estrogen levels. At this consistency it’s the perfect medium for sperm to stay alive and find their way through the cervix and into the uterus. While it is imperative to fertility, even your OBGyn may not tell you anything about it!
Cervical fluid is an incredible “vital sign”. Getting familiar with your CF patterns can help determine:
when you’re fertile
if you’re ovulating or not
why you might be having a harder time getting pregnant
if you have a vaginal infection (which is often accompanied by discharge different from normal CF)
How do you check your cervical fluid?
When you sit on the toilet before you pee, take a square of TP and blot it on the opening of your vagina. Then look at the TP. It may be dry, wet, or have lotion or egg white consistency fluid on it. If there’s something there, pick it up and feel the consistency. Is it thick? Creamy? Stretchy? Yes, I know.. it may sound weird but try it! After you know what you’re looking for, you don’t have to do this every day. When you’ve got a lot of fertile CF just wiping normally may be like a slip n slide!
What is fertile cervical fluid?
During your fertile window, CF will become thin, stretchy, wet, and like egg whites.
Not getting much fertile-type cervical fluid (or less than 2 days of wet CF)?
This is common in women coming off hormonal birth control, nearing menopause, or who have had a cone biopsy on their cervix.
Here are some tips to increase fertile cervical fluid:
Avoid drugs that may dry up cervical fluid, such as antihistamines, atropine, belladonna, dicyclomine, progesterone, or tamoxifen. If you have to take Clomid, combining it with estrogen may compensate for its drying effects. However, estrogen should never be taken without fertility drugs, since, paradoxically, that could actually inhibit ovulation.
Drink a lot of water
Use a lubricant specifically made to mimic your natural fluids. This will provide an optimal environment for sperm. Common brands include Preseed or Conceive Plus. Other oils, artificial lubricants, and even saliva can kill sperm.
Evening primrose oil taken orally provides healthy Omega 6 fatty acids gammalinolenic and linoleic acids
N-acetyl cysteine(NAC) is a natural expectorant which can help thin out CF. It’s also a precursor to glutathione, a super antioxidant which can improve egg quality. I’d recommend taking about 500mg three times a day starting a few months before TTC (to get the egg health benefits) or at least 4 days before your expected peak day (the day of most fertile CF)
Pharmaceutical expectorants like Mucinex (guaifenesin) or Robitussin (just make sure it’s plain with no other ingredients like DM) per package instructions starting 4 days before your peak day
Basal Body Temperature (BBT)
Basal body temp is your baseline temperature when you first wake up in the morning.
Taking your waking temps will help you determine whether:
you have ovulated
your luteal phase is long enough for implantation (at least 10 days)
your progesterone levels are high enough in your luteal phase
you have a thyroid problem (either hypo-or hyperthyroid)
you are still fertile in any given cycle as reflected by preovulatory temps
you may have gotten pregnant, as reflected by more than 18 high temps
you are in danger of having a miscarriage, as indicated by a sudden or gradual drop in temps after an apparent conception
you were pregnant before having what seemed to be just a “late period”
How to Track Your BBT
To track your BBT, keep a thermometer at your bedside and take your temp when you first wake up, before moving around or getting up to pee. It’s best to do this at a consistent time every morning. Then chart your temps in a fertility tracking app. There are several great apps out there but I recommend Kindara because it also has a community for support and learning how to track cycles. They also have a cute little thermometer called Wink which syncs your temps via bluetooth with the app. It can't get more easy than that!
Temps Throughout the Menstrual Cycles
Preovulatory temps usually range from about 97 to 97.7 degrees Fahrenheit. About a day after ovulation, temps rise due to increased progesterone levels which is referred to as the thermal shift. Postovulatory temps rise to about 97.8 or higher and usually stay elevated until the next period, about 12-16 days. When a woman gets pregnant her temps stay elevated for most of the pregnancy, dropping gradually a few months before birth.
Factors that can increase your BBT:
-having a fever
-drinking alcohol the night before
-getting less than 3 consecutive hours of sleep before taking it
-taking at a very different time than usual
Trouble Shooting Your Cycle
No woman's cycle is text book. We all have our own variations and many variables at play. But if you do have an underlying issue, you may see clues in your menstrual cycles.
Suboptimal Thyroid Function
-Low basal body temps and long cycles might indicate that your thyroid function is suboptimal. This could also cause irregular cycles or anovulation.
Luteal Phase Dysfunction
Can present as:
short luteal phase (10 days or less)
normal appearing LF but temps not much higher than baseline
normal appearing LF but temps drop off about a week after ovulation
This is often due to insufficient progesterone secretion from the corpus luteum. Your progesterone levels should be tested and if they’re confirmed to be low then supplementation may be appropriate. Note: your doctor might only test on a generic “day 21” but this doesn’t give an appropriate picture because it depends on what day you ovulated. Ideally we test on multiple days throughout your LF or at least day 10 after confirmed ovulation.
One abnormally long cycle among consistent cycles is often due to stress delaying ovulation. Consistently variable or long cycles may be caused by blood sugar dysregulation, hormonal imbalance, adrenal dysfunction, stress, thyroid problems (hyper or hypothyroidism), uterine fibroids, endometriosis, obesity, perimenopause, or medications. Irregular cycles may be anovulatory, meaning that you might be having a hormonal bleed but not actually ovulating.
Regardless if you’re having periods or not, if you aren’t getting any signs of ovulation (fertile type cervical mucus, temp shift) then you should see your functional medicine doctor. There are meds like Clomid and Femara that can help induce ovulation but I don’t recommend starting one of those until you’ve identified and addressed underlying causes for anovulation.
For (a lot) more information about Fertility Awareness Method and cycle tracking, I recommend reading Taking Charge of Your Fertility by Toni Weschler. The Fifth Vital Sign by Lisa Hendrickson-Jack is also a great resource, as well as her podcast, Fertility Friday.
When To Talk To Your Doctor
Get help from your functional medicine doctor if you're noticing any irregularly in cycles, low temps, no signs of ovulation, or you're #TTC ASAP. Together, we can get to the bottom of any abnormalities and optimize your fertility and egg health.
Want to chat with me one-on-one about your menstrual cycle and fertility? Schedule you free consult now.