If you get your period on a regular basis, what tends to happen is that you start to assume that you know all there is to know about your menstrual cycle. But while you may know the symptoms that happen to you and when to expect them, you may still not know the complete story of what goes on in your body. Today we’re going to be delving a little bit deeper, and talk about what happens to your body through your menstrual cycle (not just when you’re on your period) and why your body feels the way it does throughout your cycle.
A Brief Overview
The menstrual cycle lasts an average of 28 days, but differs between people. Some people have longer cycles while others have shorter cycles, and that’s perfectly natural. For the simplicity, we’ll be taking reference from a 28-day cycle.
Your period usually happens from the 1st to 7th day, and that’s when your uterine lining sheds and you expel the unfertilised ovum. From the 7th to 14th day, the uterine lining starts to thicken again, and a follicle starts to develop in the ovary. On the 14th day, the follicle bursts and releases an egg from the ovary in a process called ovulation. The egg will then travel down the fallopian tubes over the next few days and await fertilisation by a sperm. If left unfertilised by around day 25, hormones will signal the next cycle to begin, causing the cycle to restart.
Estrogen, is actually an umbrella term that includes a few chemically similar chemicals that responsible for the development of female sexual characteristics and reproduction in both humans and animals. It controls growth of the uterine lining, and causes breast development during adolescence and pregnancy as well. Levels of estrogen are higher than the levels of progesterone following the period, and drops slightly as the menstrual cycle progresses.
Progesterone stimulates the secretion of proteins that prepare the uterus to receive and nourish a fertilised egg, hence maintaining the thickness of the uterine lining. If fertilisation does not occur, progesterone levels drop and the uterine lining breaks down, causing menstruation. However, if fertilisation takes place, then levels of progesterone remain high, suppressing the breaking down of the uterine lining. Levels of progesterone are lower following the period, and only starts to increase after ovulation. High progesterone levels at the later parts of the menstrual cycle are partly responsible for your typical symptoms of PMS, such as breast tenderness, bloatedness and mood swings.
This is the part of the menstrual cycle that most people dread. With the cramping, bloatedness and discomfort that comes along with the period, it is no wonder why it has such a bad rep with ladies everywhere. But what really happens during your period?
Firstly, since your ovum was unfertilised, estrogen and progesterone levels take a dip, which causes the break down, and discharge of your uterine lining. Your uterus contracts as it expels the unfertilised ovum, and this contraction is felt as the ever so familiar menstrual cramps. Hormonal fluctuations are also the cause of the feelings of bloatedness that come along with your period. This is because when progesterone levels fall, our kidneys (which are responsible for passing our fluid) release less water it in our urine, causing more of it to be retained in our bodies.
Another reason why you may be feeling less than stellar, may be the production of the hormone prostaglandin. It causes the contraction of the muscles in your bowels, and this is why you may constantly feel like passing number 2s when on your period.
After your period, estrogen levels begin to rise again, and this causes your uterine lining to thicken, this readies your uterus to receive a fertilised ovum later on. Meanwhile, a follicle grows and matures in your ovary, and gets ready to release a mature ovum.
This is the day when the mature ovum gets discharged from the ovary into the fallopian tube, this is when you are most fertile, as fertilisation of the ovum by sperm occurs as your ovum travels through the fallopian tube. Progesterone levels steadily increase to maintain the thickness of you uterine lining, to prep for any implantation of a fertilised ovum from the 14th day to around the 25th day.
When you ovulate, you will feel a sort of twinge of pain or a series of cramps in your lower abdominal area, which is usually concentrated at one side of the torso (where the ovary you are ovulating from is). This is called mittelschmerz, and is the result of the maturation or release of an egg from an ovary. Most of the time this pain will be insignificant, but if you pay close attention during the day you think you are ovulating, you may be actually be able to feel this tingling sensation.
In addition to this, your amount of discharge you have nearing ovulation will tend to be higher that other times of the cycle, and the discharge itself is more fluid, feeling almost like raw egg whites.
Day 14 – Day 28: Pregnancy or Preparation for Period
If you’re sexually active, and fertilisation of the ovum occurs, your body will then prep for pregnancy. Meaning that progesterone levels remain elevated, and this maintains the thickness of your uterine lining such that the ovum has a dense layer of lining to be embedded in. If your ovum does not get fertilised, however, around the 25th day, your body will send signals for the levels of progesterone to drop. This then causes your uterine lining to start to break down, stimulating the beginning of a new menstrual cycle.
A week before your period, estrogen and progesterone levels are generally quite high in your system, and when they rapidly drop after the 25th day, this hormonal change may trigger your common symptoms of PMS, such as bloating, cramps, and fatigue.
And there you have it, your menstrual cycle! While there are still a ton of other things that happen in your body throughout this cycle, we hope that this article provided you with a little glimpse into what goes on inside. So you see, your menstrual cycle is actually a beautiful and highly complicated system, and shouldn’t be treated with disdain! Instead you should be thankful for your amazing body, and this cool things its capable of doing 🙂 Any questions? Leave them in the comments box below and we’ll get back to you ASAP!
Also, here’s a summary infographic so you can see it with a quick glance. (Check out all our infographics here.)
Chen Wei is an undergrad majoring in Psychology. She's currently spending a year in New York City, where she's interning at a startup. When she's not at work, you can find her practising yoga, or exploring the Big Apple with her camera in hand.