Period Hormones

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How do Period Hormones Control The Monthly Flow?

Our first step in having pain free periods is understanding period hormones. What the heck happens, from a hormone perspective, during your monthly cycle.  Endometriosis?  That is different than painful periods, but understanding the hormones is still valuable in your journey.  Post Menopausal?  Again, understanding how different hormone presence (or absence) can be related to symptoms can help you understand what your body is experiencing, and give you tools to lessen symptoms, not just cover them up!  Read on and enjoy!

What happens during the monthly flow, from a hormone perspective:

A graph of the various period hormones related to mestruation. Keys are that luteinizing hormone spikes just before ovulation, estrogen and progresterone build after ovulation, then both rapidly fall when the egg is not fertilized, leading to menstruation
A graph of the various period hormones related to mestruation. Keys are that luteinizing hormone spikes just before ovulation, estrogen and progresterone build after ovulation, then both rapidly fall when the egg is not fertilized, leading to menstruation

1. Menstrual Phase: The Bleedy Part

In this phase, old blood and various tissues (that were the lining of the uterus, in preparation for potential implantation of fertilized egg) leave the uterus through the vagina. This takes an average of 5 days, but can be 3-8. During this phase, a gland in your brain produces ‘follicular stimulating hormone’ to tell the ovaries to get busy ripening eggs, or “follicles” the fluid filled sacs that contain the eggs. Your period hormones are getting to work starting your next cycle already!

2. After your period, before Ovulation

A. Ovaries: Follicular Phase: Mid follicular phase, the biggest follicle becomes “dominant” and starts to make more Estrogen. It will be the next egg released.

B. Uterus: Proliferative Phase: After period, the uterus builds back up lining.


3. Ovulation

When the dominant follicle has produced enough estrogen, the brain releases luteinizing hormone, which causes ovulation. Ovulation is the release of the biggest egg, the dominant follicle, usually about mid-cycle, or day 14.


4. After Ovulation, Pre Menstruation

A. Ovaries: Luteal Phase: Now that the dominant follicle has been released, it closes off and becomes “corpus luteum”, producing estrogen and progesterone. Progesterone peaks mid-phase here. If the egg is fertilized, this corpus luteum supports the early embryo. If not fertilized, the corpus luteum breaks down, and the drop in estrogen and progesterone causes menstruation.

B. Uterus: Secretory Phase: the lining of the uterus produces chemicals that can support a new embryo.  The most notable of these chemicals are prostaglandins, which rise after ovulation and peak during menstruation.   If no fertilization occurs, the corpus luteum stops producing estrogen and progesterone.  This drop in estrogen and progesterone, along with presence of prostaglandins, cause the uterine blood vessels to constrict, the muscles to contract, and the lining of endometrium begins to break down and menstruation occurs.  And the cycle repeats. 


5. What if the egg is fertilized? What happens to period hormones at that time?

If the egg is fertilized, prostaglandins are inhibited, and the menstrual phase does not occur…and the hormones of pregnancy are a whole additional story.  


Phew, read this a few times, refer to the chart, to start to begin to understand what is ‘normal’ in this period hormone flux.  I recommend gently tracking your symptoms, if you are having them, for a couple of months.  You may notice a pattern, ie, ‘my breasts are regularly tender around ovulation, and worse if I am drinking a lot of caffeine.”  Or, “my low back is sore the day before my menstruation begins.”  Additionally “I get irritated bowels and loose stool the first two days of my bleeding cycle.”  All are common, and interesting, and potentially can be helped my balancing stress and hormone levels, as well as taking care of your pelvic floor!  

How do period hormones relate to common (but not normal!) symptoms of the monthly cycle?

This literally blew my mind. I was chatting with my girl, Erin Borbet, accupuncturist to the stars and guru of all that is hormone-related, about how I’ve always had extremely sore breasts in the week leading up to my period. She was like “oh, that’s common, but not normal.”

I was like… “I say that ALL THE TIME, but about incontnence and pelvic pain. Everybody ‘knows’ you are supposed to be uncomfortable before your period, right?”

She was like: “Doctor, heal thyself (okay, she didn’t say that), but she basically told me that PMS symptoms are generally due to an imbalance of the hormones. And if one becomes dominant, it can lead to sore boobs, or back, or moodiness.

Mind Blown. I had noticed, in my professional practice, that clients would report lessened period cramping after they worked on their pelvic floor muscle spasms, but I never considered having “pain free periods” as a realistic or reasonable goal. These individuals coming to see me had tailbone pain and couldn’t sit on a chair. Or had pelvic pain and couldn’t use a tampon, but wanted to have a baby. They had ‘bigger issues’ to deal with.

In my arrogance, that’s really what I thought. But I think really, it was because I didn’t know there was more to offer them. So, instead of being a part of the problem (or at least complicit in its acceptance as normal), I began to work to change the perception. We started with a fun Instagram LIVE (I am still so new to Insta! It was a hoot!), and I am continuing now with Blog posts, and outreach on other social platforms. Yes, there will even be a section in the Upcoming Pelvic Floored book! Maybe even professional continuing education, if Erin and I get around to it 😉

Summary: People who make other people, you can have a better period. How?

A future blog post will cover how fluctuations in these period hormones can cause many ‘common, but not normal’ period symptoms!

Thanks for reading! If you haven’t already, please join my mailing list to be kept up to date on other AMAZING blog posts with practical tips for improving your pelvic (and overall) health prenatally, postpartum and beyond! Mailing list subscribers also get exclusive discounts to Pelvic Floored products, and access to subscriber only events!  Don’t miss out!  Sign up Today! 

Thanks for reading!

xoxo, Dr. Kelly

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Period Hormones
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