To truly understand and manage your perimenopause symptoms, it's crucial to learn the intricate hormonal changes occurring in your body. These changes start long before symptoms show up, even though it feels like they all appeared overnight.
This article, the first in my PeriProf 101 perimenopause introduction series, provides essential knowledge for those who want to understand more about these precious hormones.
Estrogen, progesterone, FSH, LH, and testosterone, oh my!
Our female hormones, estrogen, progesterone, FSH, LH, and testosterone, control and maintain many of our body’s functions, in addition to fertility. They impact how our entire body, all of our systems, from brain function to digestion to reproduction, to name a few, work.
They also control our moods and, to an extent, our personality.1 This is brand new research recently discovered around the 1990s2 Previously, it was thought that our female hormones only controlled our reproduction.
There’s no fun in just providing you with a list of information, so let’s look at the female hormones through the lens of Winnie the Pooh Characters.
Estrogen, aka Pooh
“You’re braver than you believe, stronger than you seem, and smarter than you think.”3
If you’re familiar with Pooh, you know that Pooh is creative, sweet, friendly, steadfast, helpful, and social. When you have estrogen around, you’ll be more likely to also display these characteristics. You’ll also want to be more social and outgoing, and you’ll have a skip in your step with energy. You may smile more and feel more joyful.
Estrogen is highest in the follicular, or first half of your menstrual cycle, prior to reaching perimenopause when things start becoming erratic.
Overall, estrogen is connected to our feelings of vitality. There are 3 main types of estrogen4 in our body:
estradiol (called E2 or 17-beta estradiol)
estrone (E1)
estriol (E3)
Just FYI, there is a 4th type that our bodies make as a fetus.
During perimenopause, your body will shift from making the most potent version, estradiol, to making a less potent version, called estrone.
Estradiol is made in the ovaries and estrone is made in the adrenal glands once the ovaries no longer make estrogen. Estriol estrogen is made in your body when you’re pregnant to support the pregnancy.
Estrogen in Perimenopause
During perimenopause, your estradiol estrogen levels will fluctuate rapidly, often hour to hour, and then will flatline to zero or close to it by the time you reach menopause. Around menopause, your body will only produce estrone estrogen and this is the type of estrogen that it will produce going forward.
Progesterone, aka Eeyore
“If it’s a good morning, which I doubt.”5
Eeyore is a bit of a downer. He moves slow and has low energy. He would much rather prefer to stay home and hang out on the couch. When your progesterone is high, you may be hungrier, more tired, and more chill than in the first half of your cycle.
Progesterone’s primary purpose is to stabilize and prepare the uterine lining for pregnancy and “helps close off the cervix to any germs or sperm(s)” after ovulation.6 However, researchers are finding it plays other roles as well, including breathing regulation7 , boosting brain function by being neuroprotective (nerve health and function). 8
Progesterone is the yin to estrogen’s yang. It balances out the energy and growth estrogen brings to the body. Progesterone is made in the ovaries and is highest in the luteal phase (the last half of your menstrual cycle before perimenopause).
It crashes right before your period arrives (about 2 days, PMS anyone?). It’s this crash of the progesterone that brings on your period.
Progesterone in Perimenopause
Progesterone is the first female hormone to decline at the start of perimenopause. It’s not a sudden drop but a gradual decline over the years of perimenopause. When progesterone drops, you may feel more anxious, have difficulty sleeping, and have issues with other functions like spotting.
An imbalance between progesterone and estrogen may cause an “estrogen dominance” situation and can encourage the growth of fibroids and thyroid nodules. Estrogen loves growing things.
FSH, aka Rabbit
“You and I have brains. The others have fluff. If there is any thinking to be done in this Forest-and when I say thinking, I mean thinking-you and I must do it.”9
Rabbit is the self-appointed leader of the Pooh clan. He can be stubborn, shouts a lot, and is ready to jump into action.
FSH (follicle-stimulating hormone) is the driver of ovulation and prepares and releases an egg for ovulation. It’s made in the pituitary gland in the brain and normally rises during the first half of your cycle.
As your brain receives fluctuating high and low estrogen as you go through perimenopause, it starts making more and more FSH to try to jumpstart ovulation.
FSH in Perimenopause
In perimenopause, the brain releases more and more FSH to “shout” at the ovaries to prepare and release an egg as they start to slow down. It’s a cycle; the ovaries release less and less hormones the closer to menopause, which causes the brain to release more FSH.
I have a theory that the combination of low progesterone, fluctuating estrogen, and rising/fluctuating FSH are what causes the most perimenopause symptoms. I’ll have to wait for science to test this.
LH, aka Tigger
“Well, I better be bouncing along now, chum! Cheerio! Hoo-hoo-hoo-hoo!”10
Tigger is full of energy, bouncing and bouncing and bouncing. He’s got a positive attitude and cares about what happens in the Hundred Acre Wood.
LH (Luteinizing Hormone) is made in your brain by your pituitary gland. Its bounce at ovulation triggers the release of an egg and is at its highest level in your body during that short time. It stimulates the ovaries to produce progesterone at ovulation.
LH in Perimenopause
Another thing that happens in perimenopause is that your body stops ovulating. When this happens, you stop releasing LH.
Testosterone, aka The Lover
“I need some alone time with her.”11
Finally, we have testosterone. I need to pull in a special guest star for this hormone, John Beckwith (Owen Wilson), from the movie The Wedding Crashers. I doubt you want to think of Christopher Robin as a lover.
John and all of his testosterone were driven to pick up women at weddings, and that was why he participated in the scheme of crashing weddings. But, he also has a sweetness and sincerity about him even though it gets misplaced in his intentions.
It may surprise you to learn that women also have testosterone, just not as much as men do. It plays several important roles in our bodies, but the most notable is controlling our libido. However, keep in mind that there are many things that can affect libido, not just testosterone. Testosterone can give us the drive and interest in having sex, but there are many other factors involved in desire.
Testosterone in Perimenopause
Testosterone is made in various places in a woman’s body12 and is the last hormone to decline, usually after menopause. When this happens, it’s not considered part of the perimenopause process but rather a process of aging. However, during perimenopause, testosterone can spike higher than normal and cause things like facial hair and hair loss.
Libido also tends to tank during perimenopause and is sometimes not related to testosterone levels. Perimenopause usually starts at one of the busiest times in our lives as we juggle careers, children, and our aging parents. Symptoms can knock us off kilter, taking with it our mojo and sexual interest.
Now What?
Your body is used to this cyclical monthly dance between your hormones. When this pattern is disrupted during perimenopause, we can experience all sorts of symptoms.
Sarah E. Hill said it best in her book, This is Your Brain on Birth Control
“This means that your brain – that super-powerful CEO of your nervous system that is in charge of all the things about you that make you, you – has been programmed to act differently depending on the sex hormones being released in the body.”13
When our hormones are erratic, it has the potential to disrupt who we feel we are. The good news is that there is plenty that we can do to help ourselves feel better (more on that later).
Something else to look forward to is that once you go through the perimenopause hormonal storm, your symptoms should ease up as your body adapts to its new new of lower, yet stable, circulating hormones.
Looking for HRT information?
I’m sorry that this article does not include information on HRT, hormone replacement therapy, now called menopause hormone therapy. I’ll write an article on that at a later time. Consider subscribing to The Periprofessional so you don’t miss any upcoming articles.
For additional information, please see my Vagtionary. My female-centric guide to women’s health terms.
Be well, stay cool.
-Shelby
Disclaimer and Content Use Policy
Hill, PhD, Sarah E. This is Your Brain on Birth Control. Avery Publishing. 2019.
Mosconi, PhD, Lisa. The Menopause Brain. Penguin Random House. 2024
Pooh Quote
There is a 4th type of estrogen called Estetrol (E4), but this is only found in a fetus during pregnancy. However, some oral birth control pills are starting to feature this type as an active ingredient.
Eeyore Quote
Hill, PhD, Sarah E. This is Your Brain on Birth Control. Avery Publishing. 2019.
Saaresranta T, Polo O. Hormones and breathing. Chest. 2002 Dec;122(6):2165-82. doi: 10.1378/chest.122.6.2165. PMID: 12475861.
Felice Gersh, MD explaining progesterone on IG.
Rabbit Quote
Tigger Quote
John Beckwith Quote
Testosterone is created by the ovaries (25%), adrenal glands (25%), and 50% by the “peripheral tissues from the various precursors produced in the ovaries and adrenal glands” Guay, Andre; Davis R., Susan; Testosterone insufficiency in women: fact or fiction? Word Journal of Urology, 2002; 20:106-110.
Hill, PhD, Sarah E. This is Your Brain on Birth Control. Avery Publishing. 2019, page 42.
Great info and I like the references!!