What is the Menstrual Cycle Really About?
The menstrual cycle…. If you’re like many… and honestly even me, then this one has you nervous. As women we should be well versed in all things menstrual cycle, but I find the exact opposite is true. After spending 8 years of my life as a labor and delivery nurse and 2 years in grad school, for specifically women’s health, I still didn’t know much about the menstrual cycle… until I took the time to learn it on my own! This must stop! There is absolutely nothing to fear about the menstrual cycle and this will take you on an adventure to learn more about your body. So, get ready!
First let’s get the correct terminology.
-menstrual cycle: also known as the ovarian cycle, a hormonal cycle that includes 2 stages of hormonal fluctuations from the first day of one menses to the first day of the next menses typically about 24-35 days in length.
-Uterine Cycle: the stages of endometrial (uterine) lining change during the ovarian or menstrual cycle
-Menses: the part of the menstrual cycle that results in the shedding of the lining of the uterus, also known as the period.
-ovulation: the part of the menstrual cycle where a surge of hormones, FSH and LH release an egg
-follicular phase: the first half of the menstrual cycle, which can vary in length from the first day of bleeding on your period to ovulation; days 1-14, on a 28 day cycle, but this part of the cycle can vary in length
-luteal phase: the second half of the menstrual cycle lasting from ovulation to the first day of your period; days 14-28, on a 28 day cycle, this part of the cycle typically is 14 days due to the breakdown of the egg/ corpus luteal cyst
- corpus luteum: the “ovulatory” or follicular cyst that brought about the egg that was just released with ovulation. After “egg release” this is where progesterone is made to sustain early pregnancy
-Hormones: there are several we will discuss estrogen, progesterone, testosterone, follicle stimulating hormone (FSH), and luteinizing hormone (LH). Each has its own role, I will break them down in the stages of the cycle.
There are four stages of the menstrual cycles… yes 4. There are two hormonal stages to the follicular phase and two in the luteal phase, and each has different hormone concentrations and are broken down by approximately a week. Here I will break them down based on a 28 -day cycle which is the vast average I find in practice.
An interesting fact to throw in, is that our bodies typically follow a cycle like that of the moon, there are aprox 28-29 days between full moons. If you have ever heard about the full moon making people “crazy” this is partially why, our hormones follow the same trend. Also, if you don’t have a period, due to menopause or breast feeding, there is still a rhythm to your hormones that follows this same trend. Hormonal birth control throws this rhythm off due to artificially suppressing our natural rhythm, but we will discuss that later.
Where do hormones come from? This is important to know. Menstrual hormones, like all other hormones, first originate in our gut, but they don’t look like the hormones we know, they are precursors, or building blocks, to hormones. Some are derived from our food and others are made by the good bacteria, our microbiome, as they break down the food we ingest. This is why gut health is so important for our overall health. If you haven’t read “The Gut Reset” blog I did a couple of weeks ago, you should. After the precursors are made in our gut, they flow through the blood stream to various endocrine, or hormone secreting, organs. The primary one is the pituitary gland in the brain. The pituitary gland is responsible for making FSH, LH, and Prolactin (but we won’t talk about prolactin here, that your “milk” hormone). FSH and LH stimulate the ovaries to produce estrogen and progesterone. Testosterone is made partially in the ovaries and adrenal glands (just above the kidneys), and about half is made by the skin, fat, and other tissues throughout the body.
The follicular phase begins on the first day of bleeding on your period, this is Day 1 of your menstrual cycle.
We will reference the above image when we discuss the menstrual cycle.
The top two images are the hormone changes and effect on the ovary and the third image is the uterine lining effect. The only hormone not represented is testosterone because it stays stable throughout the cycle with only a mild increase at ovulation to increase libido.
At the bottom of the diagram are the days of the cycle with the basal body temperature trends.
Days 1-7: All hormones, estrogen, progesterone, FSH, and LH are all low and relatively stable, this is during your period and the endometrial lining is shedding off to become its thinnest layer. You will typically feel slightly moody, crampy, and fatigued and will likely have cravings due to the nutrients being lost with bleeding (check back to see the next blog that discusses common issues with the cycle)
Days 7-14: This is gearing up to ovulation, estrogen is rising rapidly and this its first peak just before ovulation, progesterone stays low, FSH raises abruptly, but the most pronounced hormonal rise is LH. It peaks with ovulation. During this time the endometrial lining quickly rises and goes through vascular remodeling, in anticipation of a fertilized egg. During this time, you should feel a large surge of energy, an boost in your mood, mental clarity, and increased libido thanks to the surge of estrogen and slight increase in testosterone
Days 14-21: Just after ovulation your progesterone surges from the corpus luteal cyst to stabilize your body in the event of conception. Estrogen declines slightly and is far overpowered by progesterone. FSH and LH both drop dramatically back to their low levels, noting that their job is complete. The lining of the uterus surges to its thickest point and the blood vessels continue to form and become superficial in anticipation of receiving a fertilized egg. You typically feel sluggish, moody, bloated, and might get constipated at this stage, thanks to progesterone.
Days 21-28: the final span of the cycle occurs when the egg is not fertilized and doesn’t implant. This signals the corpus luteal cyst to begin to break down and cause progesterone to decline. Estrogen again surges and promotes the lining vasculature to begin the shedding process. You will typically feel that surge of energy again, often described as a “relief” from the “PMS” symptoms of bloating, constipation, moodiness, and sluggishness that occurred in the previous week thanks to estrogens increase and the decline of progesterone.
This might seem like a lot of unpredictable variants, but our bodies, when functioning optimally, are well run and very organized. The cycle is predictable, for some even to the hour!
This is an example of how the menstrual cycle should work, I wholeheartedly know many women struggle with irregular cycles, pain before and during their period, intense mood swings, acne, and many other symptoms. We will discuss those next time and begin to break down how to manage them naturally.
Until next time, God Bless, keep growing, and remember, thriving is not about perfection.
