Day 3: Get to Know Your Cycle (Part 1)

Welcome to Day 3 of The Science of Your Cycle, Groove’s amazing (and 100 percent FREE) 7-day mini-course that will teach you everything you need to know about how your body (and your period) works. It may not feel like there’s anything special about having a period, but the menstrual cycle seems pretty amazing once you learn about the countless intricacies and subtle changes that are required for you to have one. Not only is the menstrual cycle really freaking cool to learn about, but understanding it can provide you with some major health benefits. In today’s video, you’ll learn what vaginal discharge REALLY is, why it’s vital for a healthy body, and why your body bothers to make it. If knowledge is power, then you’re about to become really flipping powerful!


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Video Trascript

00:00 - Welcome welcome to Day 3 of The SCIENCE of Your Cycle, the FREE and amazing 7-day course by Groove. I am your host again, Jennifer Aldoretta, and the cofounder and CEO of Groove. Day 3 is all about getting to know your cycle, and this is only part one of this — we’re going to be covering the second part tomorrow, which will also be the last part. So let’s go ahead and get started!

00:29 - Today’s goals: we’re going to learn about how your hormones work together to create the changes that happen during the first two phases of the menstrual cycle — we’re going to take all of that information that we learned over the past two days and apply it to how the menstrual cycle actually works. We’re going to understand what vaginal discharge really is and why it’s so important for your health, and also understand why pregnancy is only possible during certain parts of your menstrual cycle. Now, this point may come as a surprise to many of you, but you’re going to learn over the next few days that it is scientifically sound. It’s a well-known fact among the female anatomy and biology folks, and you’re going to learn it, so get ready because it’s it’s some amazing stuff right there. Last but not least, you’re going to learn that your body is absolutely amazing and wonderful — I know it doesn’t always feel that way, but by the end of this I think that you will agree with me.

01:37 - Here’s a quick recap of what we learned yesterday. FSH, which stands for follicle stimulating hormone, is a hormone that stimulates the development of follicles, which are sacs that house immature eggs. So FSH stimulates follicles. LH, which stands for luteinizing hormone, triggers ovulation. Estrogen create changes in the cervix, and remember those changes make a pregnancy possible. And progesterone prepares the uterus for potential pregnancy, counteracts the effects of estrogen, and heats up the body. So at a basic level, changes in estrogen and progesterone levels are triggered by changes in follicle stimulating hormone and luteinizing hormone levels.

02:37 - First, I’m going to give you an idea of why we’re learning about the menstrual cycle. The major points are because we’re led to believe that our cycles are completely mysterious and unpredictable, when in fact they’re not unpredictable at all. They’re actually quite predictable, even if they are irregular. We’re taught to believe that we have absolutely no control over how painful, how irregular, or how problematic our periods are, when in fact we actually do have control. We also are led to think that our periods show up whenever the heck they want, and there’s absolutely no way of knowing exactly when they’re coming — and this is completely false, even yes even if your cycles are irregular. I know that sounds amazing, and for me that info changed my life, because now I know which day that my period is going to start. And without fail, that is the day that my period starts! It’s incredible, and not gonna lie, that’s one of the best benefits of all this. We’re also taught that we can get pregnant any day, anytime. And that, you know, if you look at somebody the wrong way (this you know that’s exaggerating a bit), but basically if you look at somebody the wrong way, you’re bound to get pregnant. But that’s not the case. You can’t get pregnant any day, any time — there’s only certain parts of the menstrual cycle when you can get pregnant, and that’s one of the reasons that we learning this.

04:10 - So before we start, keep in mind that your body’s goal is to reproduce. I know, that’s so rude and presumptuous. That’s so stone age-era of your body, but that’s your body goal regardless of your sexual activity, or sexual orientation, or gender identity. Your body’s goal is to reproduce. Secondly, your menstrual cycle is actually made up of two cycles, which is a very interesting fact. It’s something you can wow crowds with. The two cycles of the uterine cycle, which are the changes that occur to the uterus during a single menstrual cycle, and the second is the ovarian cycle, which is the changes that occur within the ovaries during a single menstrual cycle. The vagina is naturally acidic, which keeps it healthy and keeps the right bacterial cultures present and bad bacterial cultures at bay. So it keeps us healthy, but this acidity also does something else really interesting — the acidity makes it impossible for sperm to survive in the vagina. Literally impossible — sperm die within a matter of hours in the vagina because it’s so acidic. We’ll learn more about that later. Lastly, if you use hormonal contraception, keep in mind that you do not experience a true menstrual cycle, so natural hormone fluctuations are not going to occur. This is truly useful information to understand, but you do not actually experience a true menstrual cycle on hormonal contraception.

05:53 - A quick overview of your cycle: the four phases of the menstrual cycle are menstruation, the follicular phase, ovulation, and the luteal phase. Today, we’re going to cover the first two — with menstruation and the follicular phase — and tomorrow we’ll cover ovulation and the luteal phase.

06:14 - The first phase is menstruation, also known as your period. The first day of your period marks the start of a menstrual cycle, not the end. I know for many of us, you get your period and you’re like “Ah, finally! Everything’s over.” But that’s actually just the very beginning of a series of incredible events that happened throughout your cycle. Menstruation is part of the uterine cycle, that’s part of the changes that occur to the uterus throughout your cycle. Menstruation is when the lining of the uterus sheds, and that happens when a pregnancy does not occur during the previous menstrual cycle. Lastly, menstruation typically lasts for 5 to 7 days, and it’s going to vary based on a number of factors. But that’s the general rule of thumb is 5 to 7 days for a period.

07:07 - Next up is an overview of the follicular phase. So based on its name, the follicular phase deals with follicles — which, remember, are the sacs that contain a tiny immature egg. The follicular phase is part of the ovarian cycle which includes the changes that occur in the ovaries during a single menstrual cycle. The follicular phase is dominated by the hormone estrogen, and we learned last time that estrogen creates changes in the cervix. The length of the follicular phase varies from cycle to cycle, and the reason for that is due to the last bullet point on the slide: the follicular phase is very sensitive to external factors. So things like stress, diet, exercise, sleep, and other stresses that happen in your life are going to have an effect on the length of the follicular phase. For folks who have PCOS or highly irregular cycles, this is the phase that you can blame for that. This is the phase of your cycle when the life can really vary. For folks that have PCOS, the length of your follicular phase might be months. For somebody with a regular cycle, the length of the follicular phase might be a couple weeks. During the follicular phase, the pituitary gland, which is located in the brain, makes follicle stimulating hormone, or FSH. The follicles make estrogen, and estrogen changes the cervix.

08:39 - Now we’re going to go through each one of those in a little more detail. Number one: the pituitary gland makes follicle stimulating hormone. The pituitary gland, which is located in your brain, makes FSH, which stands for follicle stimulating hormone, and FSH, as its name implies, stimulates the development of a handful of follicles, or sacs that contain an egg inside the ovaries. Follicle stimulating hormone is a hormone that stimulates follicles, and like I said follicles are tiny sacs that contain an immature egg. So the key takeaway from this: the pituitary gland makes FSH, which causes immature eggs to grow and develop.

09:43 - Number two: follicles make estrogen. FSH stimulates the follicles to grow. So that’s the first thing that happens. Then, these growing follicles actually make and release the sex hormone estrogen. The bigger they get, the more estrogen they’re going to make. These follicles actually make estrogen, and like I said the bigger they get the more estrogen they make — that’s an important thing to remember. The key takeaway from this was growing follicles make increasing amounts of estrogen.

10:38 - Thirdly, estrogen changes the cervix. So the bigger the follicles get, the more estrogen they make, and then this estrogen that’s made by the follicles triggers changes in the cervix — the cervix is the lower part of the uterus. This estrogen triggers the cervix to produce a special sperm-friendly fluid called cervical fluid. Remember I talked about how the vaginal environment is actually quite acidic and kills sperm within a matter of hours? Sperm cannot survive in the vaginal environment. The only reason that sperm can survive in the female reproductive tract is because of this fluid called cervical fluid. Cervical fluid is thick and tacky, kind of like paste or Elmer’s Glue, when estrogen is low or when the follicles are making a smaller amount of estrogen. When they first start growing, cervical fluid becomes progressively clear and slippery, similar to the texture of raw egg white, when estrogen becomes high or when these follicles are more developed and are releasing more estrogen. The important thing to note is that slippery cervical fluid can keep sperm alive in the female reproductive tract for up to 5 days. And I’m sure you’ve heard that sperm can live in the female body for up to 5 days, and that’s where that comes from. So sperm can only survive in the female reproductive tract when cervical fluid is present, and slippery cervical fluid (which, remember, is similar to raw egg white) is the most sperm-friendly type of fluid. Slippery cervical fluid is produced when follicles are getting really big and really strong, and when they’re ramping up to ovulate.

12:33 - The takeaway from this is that estrogen production increases before ovulation. Cervical fluid progresses from thick and tacky to clear and slippery to help sperm reach the egg. I know that was a lot, but that’s almost it for today — we’re almost done, so bear with me.

12:48 - Here is a quick summary of what we’ve gone over today. First of all, menstruation is the shedding of the uterine lining. The vagina’s default mode is basically an acidic sperm-killing machine, which is pretty cool. If you think about it, growing follicles make estrogen that triggers cervical fluid production. Remember, those growing follicles, which each has an immature egg, start producing estrogen as they grow. And that estrogen triggers the cervix to make cervical fluid. Next up, cervical fluid becomes increasingly wet and slippery before ovulation, allowing sperm to survive in the female reproductive tract and eventually reach the egg. Then, lastly, cervical fluid allows sperm to stay alive inside the female reproductive tract. Remember, no cervical fluid, no sperm, no pregnancy! That’s a really important thing to understand.

14:02 - Here is a gif that I thought was pretty humorous that really doesn’t need any explaining. This is basically what pops into my head when I think of the vagina, because she looks pretty angry. I hope you’re starting to agree with me that your body is pretty cool. Tomorrow, we’re going over the second half of the menstrual cycle, and I cannot wait! See you then.