A regular period is a vital sign representing our reproductive and general health.
About 14 days before your period arrives you may just be ovulating but don’t take it for granted that you are ovulating just because your period arrived. In fact, research suggests that ovulation does not take place in 16-37% of menstrual cycles. 
Just as our period arriving regularly is a sign of our health, so is the presence of ovulation.
Let’s take a look at how we ovulate, what can impact ovulation, and signs our ovaries are doing their job.
Back to Basics: Menstrual Cycle 101
Our ovaries contain eggs that develop inside follicles. Follicles are like little water baths for the eggs and the contents of this fluid that our eggs sit in impacts the quality and health of our eggs. If this fluid contains a good balance of antioxidants and anti-inflammatory compounds, and the right hormone and nutrient levels it will nurture our eggs and protect our follicles from damage.
Most research supports that we are born with all the eggs we will ever have. These eggs sit hibernating, producing just enough energy to survive. When they are finally called on to grow and be released, the maturation process takes a few months. Nurturing your eggs before and during this maturation phase provides the best opportunity for producing healthy eggs.
While 15-20 follicles will be maturing at the same time, only one follicle is chosen to reach the final stage and become the dominant follicle. If the right conditions are provided for this follicle, this will be the one to release an egg that menstrual cycle. The egg will then make its way into the fallopian tube and if it meets sperm, this is when fertilisation may take place.
The hormone Follicle Stimulating Hormone (FSH) drives the development of follicles, just as the name says. As the follicle develops, oestrogen is released from cells that surround the egg (granulosa cells that are part of the follicle). When oestrogen levels rise enough, this triggers a surge in Luteinising Hormone (LH).
LH comes from the pituitary, a small gland at the base of our brain. This hormone triggers enzymes that breakdown the follicle and ovarian wall to let the egg out. It is an incredible process and has been captured on camera once during a surgical procedure. If you want to see the photos of a follicle releasing an egg from the ovary you can see these at the New Scientist here.
Once the follicle has ruptured to release the egg, the remnants of the follicle then get to work and produce progesterone. Progesterone is essential for sustaining a pregnancy if the egg that has just been released gets fertilised and implants into the uterus.
When Ovulation Gets Disrupted
The process of growing a follicle and successfully releasing an egg relies on good communication pathways from the brain to ovary. A region of our brain called the Hypothalamus sends out signals to our pituitary at the base of our brain, which then sends out signals to our ovaries.
Parts of the body that communicate in sequence can be called an axis and ovulation relies on a well-functioning Hypothalamic-Pituitary-Ovarian (HPO) axis. When ovulation does not place as it usually should, 85% of these failures may be attributed to disruptions with the HPO axis.
What Disrupts the HPO Axis?
Elevated Testosterone: High levels of androgens, such as testosterone, can impact the balance of hormones and the ratio of LH to FSH. The ratio of LH to FSH is usually 1 to 2 in women without identified fertility issues, but in conditions such as PCOS this ratio can be as high as 3 leading to disruption of ovulation.
Insulin Resistance: sex hormones may be carried around the body by specialised proteins. Insulin resistance is related to a decrease in the production of these sex-hormone-binding proteins which may contribute further to raised levels of androgens. Controlling blood sugar and managing insulin resistance is essential for healthy ovulation.
High Inflammation: Higher levels of inflammation levels during the phase of follicle development have been associated with a lack of ovulation (or anovulation) . Inflammation is necessary for ovulation but if levels are too high, this disrupts follicle development. This inflammation underlies unruptured follicle syndrome which is a common cause of infertility with endometriosis .
Elevated Lipopolysacharide (LPS): LPS can be found in the cell wall of particular bacteria. With an increase in intestinal permeability, systemic levels of LPS can rise and this can further drive inflammation. High levels of LPS (which are seeing in PCOS, endometriosis, unexplained infertility and male factor infertility) disrupt the surge in LH and have been associated with premature ovarian insufficiency, reduce egg quality and early pregnancy loss. This is why building our microbiota diversity for a healthy gut optimises our reproductive health.
Low Energy Availability: If we are not providing our body with enough energy to meet the needs of our daily activities and basal metabolic rate, this may lead to menstrual cycle disturbance. The amount of energy we may be missing out on in our diet is predictive of menstrual disturbances. A greater energy deficit contributes to greater disruption of ovulation.
The Gut-Ovulation Connection
Why would my gut play a role in ovulation? All the elements that can disturb our HPO listed above are all linked to the health of our gut microbiota. Depending on the health of our gut microbes they can either promote or dampen inflammation. They are also the source of the endotoxin LPS. If our gut microbes are out of balance our intestinal barrier becomes more permeable, leading to an increase in circulating LPS levels.
When our gut breaks down proven prebiotic compounds they produce short chain fatty acids like Butyrate. These compounds have been shown to improve glucose homeostasis. Higher circulating short chain fatty acids also leads to better insulin sensitivity (which our eggs love) .
In women with PCOS, nurturing the gut microbes reduces androgen levels, inflammation and LPS to restore ovulation.
If you have unexplained anovulation and do not have PCOS, it is likely that your gut microbes are different from women that are ovulating regularly. Research shows that anovulation is associated with a greater abundance of Prevotella-enriched microbes that promote inflammation and a reduction in butyrate producing bacteria .
Endometriosis is also associated with more inflammatory promoting bacteria and this can be a cause of menstrual pain.
Nurture the diversity of your gut microbes will have huge benefits for healthy ovulation!
Signs of Ovulation
The gold standard way to tell if you are ovulating is to have repeat transvaginal ultrasounds to track follicle growth and rupture. This is definitely not a very accessible way of tracking ovulation. So how else can you get some clues to know if ovulation is taking place?
This method of ovulation tracking requires you to monitor your temperature daily each morning so you can detect changes across your menstrual cycle. A small rise in your morning body temperature of 0.3 degree C / 0.5 F my you let you know that ovulation has occurred.
Once our follicle ruptures to release an egg the left-over follicle produces progesterone which tells our higher brain centres to set a higher body temperature. While an increase in temperature may indicate ovulation, many other things also affect our temperature such as alcohol, sleep disruption and stress. Also, for 20% of women they may still ovulate but not have a change in body temperature .
Pee on a Stick
Measuring urine LH to determine when levels ‘surge’ is another method that may indicate ovulation. The rise in LH typically occurs 36 hours before ovulation. The type of rise in LH is not necessarily a rapid surge for all women though so tracking this can be difficult. It is also possible to have an LH surge but no ovulation, as seen in unruptured follicle syndrome mentioned above.
Cervical Mucus Monitoring
Under the influence of oesterogen, the water content of our cervical secretions increases and mucin content decreases. If your cervical mucus is very wet, stretchy and resembles raw egg white then ovulation is very close! This method of ovulation tracking is 74% accurate when compared to tracking ovulation via the gold standard of transvaginal ultrasound.
Position of your Cervix
As you get closer to ovulation, your cervix rises and becomes softer. You can read more at PCOS to Wellness’s post on Cervix Position Monitoring.
Keep Track of Your Vital Signs
So are your ovulating? Keep track of the health of your menstrual cycle (ovulation, cycle length, symptoms, bleeding etc) and continue to nurture your gut microbiota for optimal reproductive health!
Learn how to nurture your gut microbiome for pregnancy success with Create a Fertile Gut
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- 2. Lorenz, T.K., C.M. Worthman, and V.J. Vitzthum, Links among inflammation, sexual activity and ovulation: Evolutionary trade-offs and clinical implications. Evol Med Public Health, 2015. 2015(1): p. 304-24.
- 3. Mio, Y., et al., Luteinized unruptured follicle in the early stages of endometriosis as a cause of unexplained infertility. Am J Obstet Gynecol, 1992. 167(1): p. 271-3.
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