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What Happens to Your Hormone Levels During the Monthly Cycle?

Even when you're not pregnant, your body is working round-o-clock to be a cutting-edge incubator. In order to achieve this, your brain and ovaries are constantly going through hormone level changes during cycle. In this article, we'll see what hormones dominate in different cycle phases and how they influence your mental and physical fitness.
a tree under various weather conditions symbolizing hormone fluctuations during woman's monthly cycle

A menstrual cycle is the regular natural change in the female body that makes pregnancy posible. The menstrual cycle is determined by the number of days from the first day of one period to the first day of the next. Accordingly, the first day of the menstrual cycle is the first day of bleeding of the period.

The menstrual cycle has two main phases. The follicular phase or proliferative phase lasts the first 10-16 days of the cycle and a luteal or secretory phase comes right after ovulation and lasts for 14 days, ending with the menstruation.  

Your reproductive system is under the influence of hormones regulated by the hypothalamus and its gonadotropin-releasing hormone (GnRH). This hormone causes the cells in the frontal part of the pituitary gland to produce two types of hormones.

The first is the FSH or the follicle-stimulating hormone, and the other is LH, or the luteinizing hormone. These hormones travel all the way to the ovaries where they influence estrogen and progesterone level changes and aid maturing of the follicles inside the ovaries.

Some of the matured follicles will eventually become eggs and travel down the fallopian tubes to get fertilized there and then into your uterus. This complex hormone interaction is called hypothalamic-pituitary-ovarian axis.

At the end of the previous cycle, the gonadotropin-releasing hormone levels increase due to negative feedback of estrogen and progesterone (their levels drop right before periods), which also causes the increase of the follicle stimulating hormone levels.

All the hormones involved in hypothalamic-pituitary-ovarian axis rise in one period of menstrual cycle and drop in the other. All of these fluctuations have to do with ovulation, and can cause symptoms like acne, bad mood, or appetite changes.

Now let's have a look at how hormone levels change during the cycle stages. 

During the follicular phase of the cycle, you should feel your best. The increased levels of estrogen and the low levels of progesterone will give you glowing and elastic skin, and you will overall feel fresh and energized. 

High levels of FSH in the early follicular phase stimulate folliculogenesis. In the beginning many follicles grow equally but then a dominant follicle is selected. Maturing follicles produce estrogen, and due to its positive feedback  the luteinizing hormone starts to increase. High levels of estrogen and LH activate complex biochemical interactions which lead to ovulation. 

Estrogen is one of the most impactful hormones for women. It has the same importance that testosterone has to men. Estrogen in women is responsible for the stimulation of the secondary female characteristics and childbearing. Estrogen has a lot to do with other aspects of women's health, like mood stability, protecting bone health, keeping cholesterol levels under control and appearance of the skin. 

happy and calm woman in her follicular phase of cycle

You will feel most positive and between day 6 and day 14 of your cycle. Your confidence slightly grows between day 6 and day 13 of the cycle, because of your estrogen and testosterone peak. This is when you will feel most confident. Keep that in mind if you're scheduling appearances, meetings, or job interviews. Its also the best period for sport.

Your skin will have a natural hormone-induced sent days 6-14, which could affect how fragrances and perfumes "come off" on your skin. Keep in mind to go easy with perfumes during this time.

woman experiencing PMS mood swings

Ovulation is the time when the egg comes out of the dominant follicle and is waiting to be fertilized. If you're planning on getting pregnant, your greatest chance is on the day 14 before you next menstrual cycle begins 

Once the estrogen levels come to its peak, luteinizing hormone levels also rise due to positive feedback. This process kicks off the ovulation and causes the egg to be released from the ovary.

Your ovulation should be regular without any extra symptoms aside from the changes in vaginal secretion, as the cervical mucus increases in quantity and becomes clear and more elastic at this phase.

Different types of vaginal discharge are normal throughout the cycle, so don’t be alarmed if your discharge slightly changes in color and thickness.

If you feel particularly sore or sensitive during the ovulation or there is an excess amount of secretion it's possible that there are other underlying health issues worth looking for.

After the ovulation, LH as well as estrogen levels drop down. Former dominant follicle transforms into corpus luteum. Corpus luteum is a transient endocrine organ that predominantly secretes progesterone which prepares uterus inner layer for implantation of fertilized ovary.

This phase last for 14 days in most women. 

During the luteal phase your body is preparing for implantation. Progesterone levels start to increase and this is when you start experiencing symptoms of PMS, or the premenstrual symptoms. It's very likely that you won't feel very well during the luteal stage of your menstrual cycle.

The increased levels of progesterone, which is usual for the luteal phase, cause the irritable and "down" moods, as well as skin issues. A spike in the hormone progesterone can cause constipation, so keep this in mind when planning your diet.

Common symptoms of the luteal phase include all of the known symptoms of the premenstrual phase, such as:

  • Increase of the appetite 
  • Tiredness 
  • Breakouts
  • Fatigue due to premenstrual syndrome
  • Oily hair and skin.

Most women don't feel any major changes due to fluctuating hormones during the menstrual cycle. For those who do, the shifting of the menstrual cycle stages is causing discomfort and interferes with daily life. If you learn how to relieve PMS symptoms, your will understand your body better and feel more comfortable.

In the absence of a pregnancy in the late luteal phase the hormone levels start to decrease and prostaglandin levels rise. Due to these changes uterine muscles contract and the inner layer of the uterus (endometrium) sloughs. This is called menstruation or menstrual bleeding.

Its average duration is from 4 to 6 days. But if your periods last for 2-8 days it is considered to be normal.

Progesterone and estrogen start to decrease as there was no conception. Some of the common menstrual symptoms include cramping, tenderness of the skin and breasts, sudden mood swings, tiredness, headaches and migraines, as well as pain in the lower back. The average duration of menstruation is from 4 to 6 days. But if your periods last for 2-8 days it is considered to be normal.

During the menstrual phase you might feel uncomfortable, tired, and overall in a bad mood. Still, there are plenty of medicines and foods that can help you feel better.

Women who suffer from intense cramping during the period often use pain-relieving medication like painkillers, and some apply heating pads on the lower back and abdomen to ease the cramping pains.

Your period might last to longer than the average, or be more intense. This shouldn't overly concern you, but visit your gynecologist nevertheless to confirm that there are no other health issues that cause the out-of-the-norm periods. You might want to boost your diet so that you are able to compensate for the loss of the nutrients from heavy bleeding.

Here's how to improve your life by getting to know your menstrual cycle.

  • Track your cycle using a calendar and expect changes.
  • Note personal observations on a calendar and adjust diet, skincare, and activities.
  • If you're starting a diet make sure to do it on the first day of your periods. This is when your progesterone levels will be lowest, as well as your insulin levels. Insulin is responsible for creating the feeling of hunger, and when it drops you will feel less hungry than usual.
  • Adjust diet and your personal care to work with the current hormonal balance in your body. Changes in the blood glucose levels and insulin resistance due to fluctuations of progesterone also affect your appetite. By being aware of how your periods affect your insulin, you can track your appetite peaks and sudden increases in junk food cravings as a way to keep a close eye on your weight and health.

Here are the answers to the most common questions that the Flo users tend to ask about their monthly cycle. 

Are you planning to get pregnant? There are certain days of the month when you have the best chance of conception, and this has a lot to do with hormones.

In theory, it's possible to get pregnant whenever you make an attempt throughout the menstrual cycle.

With the possibility for semen to survive up to five days inside the uterus, and the possibility for a normal regular cycle to fall out of balance, it's hard to say you are "safe" from getting pregnant anytime you don't use birth control.

The rule of thumb is that your best chances of getting pregnant are during the days of ovulation. These particular days are those you shouldn't miss if you are trying to get pregnant. Paying attention to the right time for conception is even more important for couples who are in the process of IVF or treating infertility.

You can have sex on any day of your menstrual cycle when you want. Be careful having an intercourse during menstruation because sex on these days can higher the risk infections.

woman shrugging her shoulder unaware of how to plan her life around her periods
  • Schedule fewer activities during your menstruation.
  • Schedule any trips or vacations around your cycle to feel the most comfortable.
  • Pap smears are most accurate between the 9th and the 20th  day of the cycle, which is when you should schedule an appointment.
  • Periods of high estrogen levels (before ovulation and in the middle of luteal phase) of your cycle is when you are the most pain resistant and this is the time when you should schedule appointments like waxing, getting a tattoo, or visiting the dentist. 

If you're experiencing severe symptoms due to hormonal oscillations, make sure to talk to your gynecologist and run necessary tests. Because hormone imbalance can also come from other, more malicious conditions, it's wise to keep your levels in check. 

Understanding the pace of the hormonal changes during your cycle can help you adjust routines and feel more comfortable during rough times. A couple of minor lifestyle changes and calendar notes can make a difference, so make sure to sync your life with your cycle as soon as possible!


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