menstrual cycle

Menstrual Cycle: Definition And Disorders

We will explore the main myths about menstruation (period) and discuss the various menstrual disorders

Vaginal bleeding in women is known as menstruation or period and it always takes place within the same menstrual cycle, more specifically in the last phase of it. Although a natural occurrence in female biology, there are still many myths and taboos that surround the menstruation cycle.  

We will explore the definition of the menstrual cycle, the associated symptoms, and we will answer the most frequently asked questions about this topic. Lastly, we will have a look at the four menstrual phases  and the known menstrual disorders. 

What is the menstrual cycle?

Menstruation, also called period, is the vaginal bleeding that occurs in women's menstrual cycle. This happens once the egg cell released by the ovary does not become fertilized. If pregnancy doesn’t happen, your body doesn’t need the thick lining of your uterus (called an endometrium). Your lining breaks down, and the blood, nutrients, and tissue flow out of your body through your vagina.

The period takes place in the last phase of the menstrual cycle, called the luteal phase, when the endometrium starts breaking down - it had previously gotten larger in preparation for receiving the fertilized egg.

In total,  the quantity of blood lost is between 10 ml to 80 ml and it is made up of blood, endometrium tissue and other vaginal fluids. Menstruation blood is released through the vagina and it last on average between 3 and 6 days. 

The menstrual cycles begin with the menarche, the first occurrence of menstruation, which tends to happen around the age of 12 and continues until menopause, at approximately 51 years of age. 

Period symptoms

Most menstrual cycles last between 3 and 5 days and aside from bleeding there could be other symptoms associated:

  • Abdominal pain or cramps

  • Lower back pain

  • Swollen and tender breasts 

  • Cravings

  • Irritability and mood swings

  • Headaches and fatigue

When these symptoms appear before the onset of the menstruation we are dealing with the premenstrual syndrome which can result challenging for some women and it includes both emotional and physical symptoms alike. 

what is the menstrual cycle
Abdominal pain and cramps are the first symptoms of menstruation

Phases of the menstrual cycle 

Menstruation is part of a woman's menstrual cycle that prepares a woman's body for pregnancy each month. The day count for menstrual cycle begins on the first day of menstruation when blood starts to come out of the vagina.

The average length of the cycle is 28 days, but it can fluctuate between 21 and 35 days in adult women and between 21 and 45 days for younger women. Two hormones, estrogen, and progesterone are responsible for the menstrual cycle. 

The entire duration of a Menstrual cycle can be divided into four main phases:

  1. Menstrual phase (From day 1 to 5)
  2. Follicular phase (From day 1 to 13)
  3. Ovulation phase (Day 14)
  4. Luteal phase (From day 15 to 28)

The menstrual phase begins on the first day of menstruation and lasts till the 5th day of the menstrual cycle. The uterus sheds its inner lining in the form of menstrual fluid. You may experience abdominal cramps caused by the contracting uterus and abdominal muscles. 

The follicular phase also begins on the first day of menstruation, but it lasts till the 13th day of the menstrual cycle. During this phase, the pituitary gland secretes a hormone that stimulates the egg cells in the ovaries to grow. While the egg cell matures, its follicle secretes a hormone that stimulates the uterus to develop a lining of blood vessels and soft tissue called endometrium.

The third phase, known as the ovulation phase, starts on the 14th day of the cycle, the pituitary gland secretes a hormone that causes the ovary to release the matured egg cell. 

The  luteal phase begins on the 15th day  and lasts till the end of the cycle. The egg cell released during the ovulation phase stays in the fallopian tube for 24 hours. If a sperm cell does not impregnate the egg cell within that time, the egg cell disintegrates. This prompts the menstrual phase of the next cycle to begin.

Period FAQ

There are a few questions about periods that keep coming up among women. We will have a look at four of the most frequent ones related to controlling the menstruation, either accelerating or delaying it and the variation in color of the menstrual blood. 

Can the period be stopped?

It is possible to stop your period altogether but it it not advisable as menstruation is a natural and necessary part of the ovulation cycle.

There are, however, oral contraceptives that accomplish this but they should always be prescribed by a licensed physician.

How to speed up your period?

Accelerating your period is not advisable  as it can lead to imbalances in your menstrual cycle. There are, however, home remedies that can help with this. Among them we can mention taking warms baths, drinking oregano, or cinnamon infusions.

How to delay your period?

Similarly to the other methods of controlling the cycle, delaying your period could have serious side effects for your body if done for a prolonged period of time. 

Periods can be delayed using oral contraceptives or the contraceptive shot, however, these might have unexpected side effects. One homemade remedy is ingesting the juice of a lemon, with sugar and water one day before your period is meant to come; it is said to delay it by one or two days. This method is not completely safe either, as it may cause stomach pain. 



What color should it be?

Generally speaking,  the color of the period blood will variate from dark red to dark brown and even black and purple during the period days, which is a natural progression during the menstrual cycle. 

The variations in color are due to internal factors. When your period blood is bright red, it means this is the freshest blood your uterus is shedding. The longer blood has been in your uterus, the darker the color becomes. Dark red blood  has been around longer and will often show up when you wake up in the morning or when your period is a little heavier than usual. 

Seeing extremely light red or pink colored blood can happen when your period is lighter than usual or when you’re spotting.

As mentioned, the blood that sticks around the longest in your uterus will be the darkest. Most commonly, this blood will be brown, but it’s not abnormal if it’s black

If you’re seeing dark blue or purple bleeding, it means you have too much estrogen in your system. 

Menstrual disorders
Oral contraceptives are often used as a method of controlling the menstrual cycle

Menstrual disorders

Some women get through their monthly periods easily with few or no concerns. Their periods come like clockwork, starting and stopping at nearly the same time every month, causing little more than a minor inconvenience.

However,  other women experience a host of physical and/or emotional symptoms just before and during menstruation. From heavy bleeding and missed periods to unmanageable mood swings, these symptoms may disrupt a woman's life in major ways.

1. Polymenorrhea

Polymenorrhea is a term used to describe  a menstrual cycle that is shorter than 21 days. A normal menstrual cycle is between 24 and 38 days long.

2. Irregular menstruation 

Menstrual bleeding is considered irregular if it occurs more frequently than every 21 days or lasts longer than 8 days. Missed, early, or late periods are also considered signs of an irregular cycle.

3. Blood clots

Blood clot formation is most common during heavy blood flow days. For many women with normal flows, heavy flow days usually occur in the beginning of a period and are short-lived. 

4. Heavy menstruation

Also known as menorrhagia, it represents the increase of the menstrual blood flow over 80ml or prolonged bleeding that exceeds seven days. 

5. Hypomenorrhea

Hypomenorrhea or hypomenorrhoea, also known as short or scanty periods, is extremely light menstrual blood flow. It is the opposite of hypermenorrhea which is more properly called menorrhagia.

6. Oligomenorrhea

Oligomenorrhea is a condition in which you have  infrequent menstrual periods. A woman who regularly goes more than 35 days without menstruating may be diagnosed with oligomenorrhea.

7. Amenorrhea

Amenorrhea is  the absence of menstruation, specifically one or more missed menstrual periods. Women who have missed at least three menstrual periods in a row have amenorrhea, as do girls who haven't begun menstruation by age 15. 

8. Dysmenorrhea

Dysmenorrhea is the medical term for menstrual cramps, which are caused by uterine contractions.

Primary dysmenorrhea refers to common menstrual cramps, while secondary dysmenorrhea results from a disorder in the reproductive organs.

Ways to track your period

Aside from the classic pen and paper method, the other two popular ways of tracking the menstrual cycle are the period calendar and the period calculator. 

These methods are useful when planning a pregnancy, or a visit to the gynecologist, among others. 

1. Period cycle calendar

The period cycle calendar or the ovulation calendar is  a method of estimating a woman's fertility  that takes into account the days in the menstrual cycle. 

This calendar-based method was developed by Japanese gynecologist Kyusaku Ogino and perfected by Austrian doctor Hermann Knaus - thus creating what we know today as the Knaus–Ogino method. Always has an online cycle calendar which you can find here

2. Menstrual calculator

On the other hand, the menstrual calculator is another tool that can be used to determine a woman's menstrual cycle and her fertile days. 

This calculator also indicates the days with the highest ovulation chances  in such a way that the chances of pregnancy could be increased. 

3. Period apps

Nowadays, one of the most popular methods of keeping track of the menstrual cycle is via period apps. 

The apps are continually developing and have reached a stage where you can add more information about the symptoms  associated with the period. 

Period tracker Flo, Period tracker, and Clue are among the most used mobile period apps. 

sex during your period
Having intercourse while on your period is natural but it does not protect from pregnancy.

Sex during your period

One myth about the menstruation cycle is associated with having sex during your period.  Menstruating shouldn't deter people from enjoying an active, healthy sex life. 

There are, however, still many preconceived ideas about menstruation which we aim to discuss in the following excerpts. 

1. Increased sex drive

Generally speaking, during the menstrual cycle,  women's hormone levels increase which affects their libido. While it's not true for all women, there is normally an elevated sensitivity in the genital area and the breasts. 

While some women say their sex drive increases during ovulation,  which is about two weeks before your period, others report feeling more turned on during their period.

2. Natural lubrication

Menstrual blood acts as a natural lubricant which can come in handy if you want to have sex during your period.

3. Not a contraceptive method

Despite the many myths, having sex while on your period does not prevent pregnancies.  While the odds of procreating are definitely lower during the period, it does not rule it out and some women who experience irregular periods risk becoming pregnant at this time. 

This is why using a condom is necessary regardless of whether or not the woman is on her period. 

4. Risk of spreading or catching STDs/STIs

Having unprotected sex during the period increases the risk or spreading or catching a sexually transmitted disease (STD) or a sexually transmitted infection (STI). These viruses live in blood, and they can spread through contact with infected menstrual blood.

5. Best positions 

The best sex positions while on your period should be comfortable so perhaps you want to try something different than what you normally do. For example, you may want to try lying on your side with your partner behind you.

Menstruation and pregnancy

After being released by the ovary, the egg cell travels down the fallopian tubes and stays there until a single sperm fertilizes it. Normally, the egg survives for 24 hours outside of the ovary.

After ejaculation, sperm can survive in a woman's reproductive system for 5 days and if the woman in question had intercourse five days prior to her ovulation there are chances she will fall pregnant.

In case fertilization does not occur, the egg disintegrates. It bears repeating, that although the chances are slimmer, unprotected sex during the period can still result in pregnancy. 

Original article in Menstruación (período): qué es, trastornos y cómo controlarla. 


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