Blog Wellness Back to basics: What’s really going on during your period?
Back to basics: What’s really going on during your period?
Back to basics: What’s really going on during your period?

Did you know that menses, better known as your period, is only one part of the entire menstrual cycle? If you didn’t, you’re not alone! 

Roughly 50% of women have a lack of understanding about their menstrual cycle 1, 2

Many of us need more education on topics like the causes of menstrual cramps, perimenopause, premenstrual syndrome, dysmenorrhea, amenorrhea (and the list goes on!). We’re not going to dive deep on all those topics here, but instead, get back to the basics to learn about the phases of your menstrual cycle.

So, what is a menstrual cycle?

A menstrual cycle is the time frame starting on the first day of menses – your period – until the day before starting your next period. Typically, a menstrual cycle lasts on average 28 days, but keep in mind, this number is just an average. In reality, everybody is different and normal menstrual cycles can range in length from 21-35 days 3

The menstrual cycle has two distinct phases; the first half of the menstrual cycle is called the follicular phase, and the second half is called luteal phase. During each of these phases, chemical messengers called hormones can cause the physical symptoms we experience. In between these two phases is ovulation, which is when your ovary releases an egg to be fertilized by sperm. 

First half: Follicular phase

During the first 3-7 days of the menstrual cycle, when reproductive hormones like estrogen, progesterone, and luteinizing hormone are low, we experience a period (and all the symptoms associated like pelvic/abdominal pain, cramps, and lower back pain). As we move from around  day 7-14 of the menstrual cycle, our reproductive hormones (particularly estrogen and luteinizing hormone) start to increase. In fact, luteinizing hormones will increase rapidly just prior to mid-cycle – around day 14 – stimulating a process called ovulation. 


When these hormones (i.e., luteinizing hormone) levels reach a certain concentration, they trigger ovulation or the release of an egg from ovaries, which marks the half-way point of the menstrual cycle. Importantly, ovulation is an indication of a healthy menstrual cycle.

Second half: Luteal phase

After ovulation, we enter the second half of the menstrual cycle, starting around day 15, where the body starts preparing for potential pregnancy. Between days 15-21, reproductive hormones progesterone and estrogen start to rise again. These hormones stimulate the tissue in the uterus to start plumping up and get ready for a fertilized egg (i.e., when sperm enters the egg released during ovulation). If this fertilized egg settles into the tissue of the uterus, this could lead to a pregnancy. However, if this does not occur, the body senses that it is not pregnant and hormone levels start to decrease during the last week of the cycle – this is where we could typically experience symptoms associated with premenstrual syndrome (PMS). 

Then, the entire process repeats itself, as the tissue and fluid in the uterus that was built up during the cycle gets sloughed off and we have a period, starting the next menstrual cycle.  

What’s the point of a period? 

Most of us do not enjoy getting our period, due to the pain and discomfort we experience in our lower abdomen and back. But getting a regular period is an indication that your reproductive system is functioning correctly. When you start having irregular periods (called oligomenorrhea), or lose your periods altogether (called amenorrhea), this is your body’s way of saying something is not right. 

Overall, your period is a barometer for your reproductive health.

Here are some reasons why you may be experiencing irregular or absent periods, which can require medical attention 4:

  • Stress. When you are under stress, this could impact the parts of the brain (called the hypothalamus and pituitary gland) that sends the chemical signals to the ovaries 5. Essentially, under stress, less chemical messengers are released from these parts of the brain, which means the ovaries are not receiving adequate signals to ovulate each cycle. 
  • Energy deficiency. When you don’t consume enough calories to account for how much exercise/physical activity you do on a daily basis, your reproductive system gets suppressed 6, 7. Energy deficiency impacts the same area of the brain as stress, leading to less chemical messengers being released to the ovary. The good news is that by increasing your daily calories, you can recover your period 8
  • Underlying medical conditions. Conditions related to outflow tract abnormalities, premature ovarian insufficiency, disorders of the hypothalamus, pituitary gland or endocrine gland, or chronic disease can cause irregular or absent periods and require medical attention to treat 9

Experiencing period pain? Here’s what might be going on.

A healthy reproductive cycle is not always pain-free. As hormone concentrations change during the different phases of the menstrual cycle, we can experience pain and discomfort. Here are some reasons why this happens: 

  • During your period. This pain is due to the production and release of prostaglandins just prior to, and during, your period. Prostaglandins are another type of chemical that can cause you to experience physical symptoms. Specifically, these messengers reach the uterus where they can cause blood vessels to constrict and stimulate the muscle of the uterus to contract, leading to the pain and cramping typically felt during the first several days of the period. 
  • During ovulation. Some people can experience short duration cramping or pain on one side of the lower abdomen during ovulation. This is because the egg gets pushed from inside one ovary into the abdomen to potentially be fertilized by sperm. 
  • During PMS. Cramping and pain of the lower abdomen and low back in the days leading up to your period is caused by the same prostaglandins that affect you during your period. 

Luckily, we have powerful tools at our disposal, like transcutaneous electrical nerve stimulation (TENS), to target pain and discomfort throughout the menstrual cycle. The PowerDot Period Pain Relief Program is specifically designed to help relieve period pain naturally, and can be used whenever you have lower abdominal and back pain.

If you’re one of the (many) people who experience cramping and pain during your menstrual cycle, try the PowerDot Pro Bundle, which includes the Butterfly Back Pad specially designed for lower back pain relief. 

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