Most Catholic marriage preparation programs now include an introduction to some kind of fertility awareness-based method, or what used to be called natural family planning. This introductory class covers the basics but is only an introduction. It’s up to the couple to pursue learning a method that works for them. There are many: Creighton Model, Billings Ovulation Method, Marquette Model, sympto-thermal, basal body temperature (BBT), and others that measure urinary metabolites. (See the bottom of this page for links to these methods.) There are also several devices that help you track your cycle like TempDrop, Clearblue, Ava, and the Oura Ring.
For some couples struggling to get pregnant, knowing how to pinpoint their fertile window and make use of it might be their solution. In couples of normal fertility, using the Creighton model to try to conceive resulted in 98% of couples achieving pregnancy by the sixth cycle when using at least one day of fertility for intercourse. Other studies have found similar results. Being able to identify and utilize the day of ovulation and the two days preceding it leads to a significantly higher chance of pregnancy.
But learning a fertility awareness-based method is about more than just knowing when ovulation or your period is coming. The female cycle has been called the woman’s fifth vital sign by the American College of Obstetricians and Gynecologists because it communicates important information about a woman’s hormones, fertility, and overall health. Learning about your cycle can help you achieve/avoid pregnancy, understand your energy, mood, sex drive, and cravings, interpret symptoms that could point to a hormonal or reproductive issue, and empower you to understand your own body and advocate for yourself with medical professionals.
Knowing which fertility awareness-based methods have medical management protocols can be very helpful in seeking care. There are only three methods that have the restorative, science-backed medical component: Creighton Method (NaPro Technology), FEMM, and NeoFertility.
The woman’s cycle consists of four phases: menstrual, follicular, ovulatory, and luteal. Cycle length varies more than the stereotypical 28 days; the normal range is 21-35 days, but the ideal range is 24-32 days. Furthermore, we know that if certain phases are too long or too short that that can indicate dysfunction. Each phase of the cycle has its own hormonal changes and even physiological changes – let’s get into them.
Menstrual
The first day of your cycle is the first day of your period, or your menstrual phase. During your period, your reproductive hormones are low. These low levels of estrogen and progesterone cause low energy levels. You might also feel less inclined to socialize, have less drive to be productive, have low libido, and even experience lessened verbal fluency and reduced memory.
A healthy bleed lasts from 3-7 days and has minimal clotting. Clots and heavy bleeding could indicate too much estrogen in the previous cycle. Brown bleeding or spotting leading up to your period could indicate low progesterone at the end of your previous cycle. Brown or black bleeding at the end of your period could point to endometritis (a uterine infection). Note: It’s important to analyze the color of the blood when you wipe, not what is seen in your period products as blood changes color when it oxidizes.
Common period symptoms include cramping, headaches, cravings, fatigue, diarrhea, period flu, brain fog, and bloating. But just because these symptoms are common doesn’t mean they are normal. You can alleviate cramping by supplementing with magnesium glycinate, drinking raspberry leaf tea, mild exercise like walking especially during the first couple of days, keeping your feet warm, aromatherapy with lavender, and avoiding sugar, caffeine, and alcohol in days leading up to period.
Follicular
Once your period ends, the follicular phase begins. It’s called “follicular” because your follicle-stimulating hormone (FSH) is rising, which stimulates the ovaries to grow a few fluid-filled sacs called follicles. Each follicle contains an egg, and one follicle will become the dominant (biggest) one, which will eventually release the egg (ovulation).
Your estrogen and testosterone levels are also increasing, which has many positive effects: higher physical and social energy, more drive, productivity and creativity, and increasing libido. You also have better emotion recognition performance. Estrogen also increases serotonin and serotonin receptors, so you feel more optimistic, hopeful, and happier. And, also thanks to rising estrogen, you even feel and look prettier!
Besides all this, estrogen is also telling the uterus to grow a healthy, nourishing lining for a potential implantation.
During the follicular phase, your basal body temperature (BBT – your body’s resting temperature, typically measured first thing in the morning before getting out of bed) stays in the lower range, generally between 97 and 98 degrees Fahrenheit. You will need to use a special basal body thermometer to measure your BBT as you need it to read to the second decimal (for example, 97.43 degrees), and ideally you would take your temperature at the same time every morning. Please note that drinking alcohol the night before can affect your BBT as alcohol interferes with your body’s ability to regulate its temperature.
Another biomarker of fertility is cervical mucus, a natural discharge you might notice when wiping. Cervical mucus changes throughout the cycle in response to the rise and fall of estrogen and is an accurate indication of where you are in your cycle. The role of cervical mucus is to nourish sperm and guide them toward the egg. Right after or shortly after your period ends, you might see sticky or tacky, opaque white cervical mucus, which over time changes to partially clear/partially opaque and stretchier. From there, it changes to what’s called “egg white mucus,” which is completely clear, very stretchy, and sometimes even slippery. The clearer and stretchier the mucus (and the more of it there is), the closer you’re getting to ovulation!
Ovulatory
The third phase is ovulation, the star of your cycle and what everything has been leading up to thus far! Your estrogen and testosterone are peaking, which gives you even more energy and a greater sex drive. These high hormone levels also make it easier for you to get aroused and to orgasm. Your luteinizing hormone (LH) surges, triggering the dominant follicle to release the egg.
Your cervical mucus during the ovulatory phase is “egg white mucus”: clear, stretchy (1-2 inches), slippery, and abundant.
Did you know the egg is the largest human cell and can actually be seen with the naked human eye? It contains 100,000 to 600,000 mitochondria, which is more than any other human cell, to power the development of the embryo. Also, the egg chooses which sperm to let in to fertilize it. An egg takes about 90-120 days to go from dormant to developed to ovulation, but once ovulated, the egg only lives for 12-24 hours before it disintegrates.
Lots of interesting changes happen in women due to the high hormone levels:
- Your sense of smell is heightened.
- Your pain tolerance is greater.
- You can lose up to a half inch in your waist, and your breasts become more symmetrical.
- Your skin gets more circulation and hydration, making it plump and glowing. Hormonal acne from your period usually clears up.
- Your verbal skills, memory, drive, charisma, and social drive are at their highest.
- Some women experience anxiety around ovulation due to the high hormones.
- Some women experience ovulation pain.
Some women ovulate, or have peak day (the last day of fertile, egg white mucus), on pretty much the same day every cycle. But ovulation can be impacted by stress, illness, and downstream effects from hormonal disruptions earlier in the cycle.
If you are tracking your BBT, you might see a slight dip in temperature on the day of ovulation.
Luteal
After ovulation, the follicle that released the egg transforms into a temporary organ called the corpus luteum (“yellow body”) that begins to produce progesterone. Progesterone is the dominant hormone of the luteal phase. The normal luteal phase is 11-16 days, but the ideal luteal phase is 13-15 days. Anything 12 days or shorter could be an indication of luteal phase defect (insufficient progesterone). Luteal phase defect can be a contributing factor to infertility.
Egg health and ovulation are related to progesterone production. A healthy egg in a strong ovulation is correlated to a healthy corpus luteum and better progesterone production.
The luteal phase has a lot of hormonal fluctuations, especially if you don’t get pregnant. Progesterone rises, peaking about a week after ovulation. Progesterone maintains the lining of the uterus, and during the luteal phase, specialized glands in the endometrium begin to secrete nutrients to nourish a potential implanted embryo. Estrogen will reach a second – but lower – peak about a week after ovulation as well. If you’re not pregnant, then estrogen and progesterone will drop, which triggers your period.
The sudden drop in hormones, especially if progesterone is too low in relation to estrogen, can cause PMS. Your serotonin levels are also fluctuating, dropping as estrogen declines, which can make you feel sadder and more tired.
Similar to estrogen having an impact on mood, mind, and energy, progesterone has its own effect. Progesterone can help you feel mellow and relaxed, have reduced anxiety, and get better sleep. But it can also cause constipation by relaxing the smooth muscles of the intestines.
During the luteal phase, your response to emotional stimuli is measurably different. One study found that women in the mid-luteal phase had faster reaction times to angry and sad emotional stimuli than women in the follicular phase. Another study shows that women in the mid-luteal phase had higher levels of social feedback anxiety. A third study found women in the late luteal phase had significantly reduced responses to happy facial expressions in men.
Cervical mucus typically dries up after ovulation because estrogen has declined and progesterone has increased. You might be completely dry or have vaginal discharge that is white and creamy (but not stretchy), similar in texture to lotion. This discharge is not “fertile.”
Progesterone also causes your basal body temperature to rise, which can be seen in a BBT chart. Three consecutive days of temperatures increased by at least 0.5 degrees F compared to the days before indicates that ovulation has occurred. Temperatures will come back down 1-2 days before your period starts. Note: Tracking your BBT cannot tell you when ovulation will occur, only that it has already occurred. If you do not have a rise in BBT, you probably haven’t ovulated. If your BBT doesn’t stay elevated for enough days, that might signal insufficient progesterone.
Resources
The below resources are different methods and sources for learning various fertility-awareness based methods.
Catholic Infertility Resources 