What are the most dangerous days of menstrual cycles?

The egg released by the ovaries during the menstrual cycle has a lifespan of a few hours to 2 days. 1 to 2 days during which you are fertile. 1 to 2 days which represent the most dangerous days of your menstrual cycle. But when does it take place? Is it regular? Can you trust your body and your menstrual cycle to know your fertile days? We answer these questions together.

The importance of understanding the 4 phases of the menstrual cycle

To understand and anticipate the most dangerous days of your menstrual cycle, it is necessary to understand how it works. The menstrual cycle is a finely orchestrated biological process that takes place each month in the bodies of women and all menstruating people. It takes place in four phases .

The menstrual phase

The menstrual phase begins when the endometrium, or the inner lining of the uterus, sheds and is expelled from the body: this is menstruation . This phase, which generally lasts 3 to 7 days, marks the start of the menstrual cycle. It is often associated with symptoms like abdominal cramps, bloating and mood swings. This phase is not considered dangerous from a fertility point of view .

The follicular phase

The follicular phase begins on the first day of menstruation and lasts until ovulation. Under the effect of the hormone FSH, several follicles grow in the ovaries, although only one usually reaches maturity. This phase is characterized by a gradual increase in energy, a stable mood and a gradual increase in libido. From a fertility point of view, it is supposed to be safe since no eggs have yet been released .

The ovulatory phase / Ovulation

Ovulation is the phase during which the follicle releases a mature egg in response to a surge in the hormone LH. This short period represents the time of peak fertility for women – these are the dangerous days during which the newly released egg travels through the fallopian tubes. Some women may notice clear, stringy cervical mucus, and experience subtle ovulatory pain, in the form of a mild abdominal cramp.

The luteal phase

Following ovulation, the empty follicle transforms into the corpus luteum, producing primarily progesterone to prepare the uterus for implantation of the fertilized egg, if applicable. If the egg is not fertilized, the corpus luteum disintegrates, causing a drop in hormones and the onset of menstruation. During this phase, premenstrual symptoms such as breast tenderness, fatigue or mood swings may occur.

And the fertility window

To determine which days are dangerous it is important to understand what the fertile window is. This is the moment when the egg released by your ovaries travels through the fallopian tubes in peak health to settle in your uterus.

What is the fertile window?

The fertile window is the 24 to 48 hour period following the release of the mature egg from the ovary. The egg is then ready to be fertilized and it moves through the fallopian tubes towards the uterus. The whole body is then ready for fertilization: the vagina secretes slippery whitish discharge, which facilitates access to sperm, the walls of the uterus are covered with endometrium to better accommodate the fertilized egg.

Which days of the menstrual cycle correspond to the fertile window?

The days of the menstrual cycle which correspond to the fertile window are the days following the ovulation phase. In a cycle of average duration (i.e. 28 days), these days correspond to days 14 to 16 of the menstrual cycle.

This being said, sexual relations should not be suppressed during this period only. Indeed, the lifespan of sperm varies between 2 to 5 days in the genital tract of women . Thus, the oocyte can be fertilized by a sperm released up to 5 days before ovulation. It will therefore be necessary to avoid sexual intercourse with penetration and vaginal ejaculation 5 days before the fertile window: from day 9 to day 16.

The importance of egg and sperm lifespan

Once the egg is released from the ovary, it travels into the tube where it can survive for 12 to 48 hours. The survival time of sperm in the female genital tract varies from 2 to 5 days, but their optimal mobility period is 48 to 72 hours. Post-ovulatory mucus destroys sperm within 2 to 3 hours.

As explained a little above, it is essential to take the lifespan of sperm into account. Indeed, the oocyte just released can be fertilized by a sperm from sexual intercourse that took place up to 5 days before ovulation.

What are the fertile days according to the length of the menstrual cycle?

While the length of a menstrual cycle is on average 28 days, this figure is only an average. The “normal” length of a menstrual cycle is therefore 24 to 32 days. To find out more about the length of menstrual cycles , you can consult our article on the subject.

“Normal” menstrual cycle

The menstrual cycle is said to be normal when it lasts between 24 and 32 days. In the majority of diagrams and models that you will find of the menstrual cycle, it is reduced to 28 days. Within the framework of a 28-day menstrual cycle, the phases of the menstrual cycle are distributed as follows:

• The menstrual phase from day 1 to 7
• The follicular phase from day 1 to 14
• The ovulatory phase / ovulation on day 14
• The luteal phase from day 14 to 28

The fertile days for a cycle lasting 28 days are therefore:

• The 2 days following ovulation, i.e. from day 14 to day 16

The dangerous days for a cycle lasting 28 days, days during which sexual intercourse with penetration and vaginal ejaculation should be avoided are:

• The 5 days preceding ovulation, i.e. from day 9 to day 14
• The 2 days following ovulation, i.e. from day 14 to day 16

Short menstrual cycle

The menstrual cycle is said to be “short” when it lasts less than 24 days. It is considered irregular/abnormal when it is less than 21 days over a period of more than 6 months: because the duration of the cycle can be a sign of a health problem, it may be interesting to consult a health professional. health to check that everything is okay.

In the context of a short cycle, it is the follicular phase which is shorter while the luteal phase is similar to that of a normal cycle. So, if your menstrual cycle lasts 22 days, the phases of the menstrual cycle are distributed as follows:

• The menstrual phase from day 1 to 7
• The follicular phase from day 1 to 8
• The ovulatory phase / ovulation on day 8
• The luteal phase from day 8 to 22 (the luteal phase always takes 14 days, the calculation is obtained by subtracting 14 to 22).

The fertile days for a cycle lasting 22 days are therefore:

• The 2 days following ovulation, from day 8 to day 10

Dangerous days for a short menstrual cycle lasting 22 days, days during which sexual intercourse with penetration and vaginal ejaculation should be avoided, are:

• The 5 days preceding ovulation, from day 3 to day 8
• The 2 days following ovulation, from day 8 to day 10

Long menstrual cycle

The menstrual cycle is said to be “long” when it lasts more than 32 days. It is considered abnormal when it is greater than 38 days over a period of more than 6 months. Since the length of the cycle can be a symptom of a health problem, such as polycystic ovary syndrome (PCOS), we recommend that you consult a healthcare professional to check that everything is okay if your cycle exceeds this duration.

In the context of a long cycle, the follicular phase lengthens and ovulation is later while the luteal phase is similar to that of a normal cycle (14 days). So, if your menstrual cycle lasts 34 days, the phases of the menstrual cycle are distributed as follows:

• The menstrual phase from day 1 to 7
• The follicular phase from day 1 to 20
• The ovulatory phase / ovulation on day 20
• The luteal phase from day 20 to 34 (the luteal phase always takes 14 days, the calculation is obtained by subtracting 14 to 32).

The fertile days for a cycle lasting 32 days are therefore:

• The 2 days following ovulation, i.e. from day 20 to day 22

Dangerous days for a long menstrual cycle lasting 32 days are:

• The 5 days preceding ovulation, i.e. from day 15 to day 20
• The 2 days following ovulation, i.e. from day 20 to day 22

Learn to detect your ovulatory phase

As you will have understood, the fertility of menstruating people is therefore linked to ovulation: it is essential not to have unprotected vaginal intercourse in the 5 days preceding ovulation and in the 2 days following it. This is why knowing how to spot ovulation in your cycle is interesting.

Start by knowing your cycle

To detect your ovulation , the first step is to know the length of your menstrual cycle. As we have seen, ovulation varies depending on the length of your cycle. Start by calculating your cycle and thus get a better idea of ​​your ovulatory phase.

To do this, three steps:

1. Identify the start of your menstrual cycle – it starts on the first day of your period
2. Count the days from this first day until the occurrence of a new cycle (it will be marked by the return of your period). To count, you can use your calendar by checking the date of your period and/or use a period and cycle tracking application.
3. Repeat the operation at least 3 times: menstrual cycles can vary enormously in their duration, which is why it is interesting to count the duration of your cycles over several consecutive cycles. This will be all the more important as the occurrence of the ovulatory phase depends on the length of the menstrual cycle.

Once you know the length of your menstrual cycle and if, and only if, it is regular in duration, you can estimate without much error which days are dangerous in your menstrual cycle.

Your body sends you signs, learn to detect them

Beyond tracking the length of your menstrual cycle, there are physical signs that can tell you that you are ovulating and therefore particularly fertile.

Cervical mucus

Around the time of ovulation, cervical mucus (it corresponds to vaginal discharge) becomes clearer, elastic and stringy, it resembles the texture of egg white. This change in your mucus is intended to make it easier for sperm to move through the cervix.

Basal temperature

After ovulation, it is common to see a slight increase in basal body temperature (BBT) . By measuring BBT each morning, many women can detect this small rise, indicating that ovulation has occurred. To measure your body temperature easily, you can use a basal thermometer.

Discover

You can record the observation of your temperature and your cervical mucus in a menstrual record provided specifically for this purpose. This will allow you to easily identify your fertile window and the dangerous days of your cycle if you do not want to get pregnant.

I want my notebook

Observing your cycle through temperature monitoring and observation of cervical mucus is called symptomothermy. To find out more about symptomothermy, read our article Symptothermy, a great tool for deciphering your cycle to find out everything about your cycle.

Ovulatory pain

Some menstruating people feel a pinpoint pain on one side of the abdomen, usually called “ovulatory pain”, “mid-cycle pain” or “mittelschmerz”. This pain may indicate the release of the egg from the follicle.

Natural solutions such as Miyé's soothing anti-pain serum can help you reduce this feeling or even Gyneika's anti-menstrual pain food supplements .

I want this anti pain serum

For some women, the pain around the time of ovulation can be very severe. In this case we recommend that you use the Bluetens electrostimulation device which will cut off the pain message!

Are you afraid of making a mistake? Use dedicated tools

Whether your cycle is too irregular to follow it this way or the physical signs don't seem so easy to follow, you can use tools to help you better monitor and understand your body.

Ovulation tests

Available in pharmacies, ovulation tests measure the concentration of luteinizing hormone (LH) in urine. An LH surge usually precedes ovulation by 24 to 36 hours. These tests are sold mainly for women with baby plans, but you can use them to get to know your body better: however, they may be expensive for contraceptive purposes.

Symptothermy

We talked about it just above, symptomothermy is the study of the menstrual cycle by monitoring and interpreting 2 parameters: basal temperature (resting body temperature) and cervical mucus .

With good training (and yes, the best is to be accompanied by a professional in this learning) and rigorous practice (you must do this monitoring every day), symptomothermy is one of the most effective contraceptives . And what's more, this method is 100% natural. We tell you EVERYTHING about symptomothermy in the article Symptothermy, a great tool for deciphering your cycle .

Mobile apps

Many menstrual cycle tracking apps use algorithms to predict ovulation based on user-provided data, such as cycle length, basal temperature, and other symptoms. They also have the advantage of telling you the dangerous days of your cycle (those moments surrounding ovulation and during which you can be fertile). Even more so and because they are on your phone, you have them with you at all times (unlike a paper tracking calendar). Be careful, however, in the event of an irregular cycle because the algorithm of these apps is often very limited and sometimes offers a fairly approximate estimate, especially if your cycle never has the same duration.

Beware of the myth of “safe days”

We would not be 100% relevant in this article if we did not take the time to dwell on this myth of safe days. There would be dangerous days (those around ovulation) and safe days, during which you could have vaginal intercourse without fear. In theory, this “safe days” myth is real. But not in practice.

In practice, thousands of factors can come into play…

• Your menstrual cycle can be disrupted for a month and become longer for multiple reasons: stress, weight gain or loss, travel, etc. Because the length of your cycle changes, so does your ovulation date and the dangerous and safe days change;
• You can release two eggs at the same time, or at different times: it happens that two eggs are released by your ovaries. In this case, it is difficult to know exactly when you are fertile or not;
• Your egg may live a little longer than the supposed 48 hours;
• Your partner's sperm may live a little longer than the expected 2 to 5 days;
• You know when your ovulation is of course... but the lifespan of sperm is 5 days, you must therefore stop vaginal intercourse with ejaculation 5 days before ovulation to avoid any risk: identifying your ovulation is therefore not enough ...

In other words, if the myth of “safe days” is a reality (as a menstruator you are not fertile on a daily basis) BUT cycles can be so fragile and so changeable that calculating your “dangerous days” does not is not enough to avoid pregnancy . If you wish to use this method as a means of contraception, it will be interesting to combine it with other tools to avoid any risk.

To avoid pregnancy, consider choosing a suitable contraceptive method

Generally speaking, if you are trying to avoid pregnancy, it will be best to adopt a contraceptive method adapted to you. It is not easy to find the right shoe for you: all methods have positive and negative points and their practicality will depend on your criteria. Here is a list of contraceptive methods to add to tracking your ovulation and dangerous days in your cycle to prevent pregnancy.

Hormonal contraceptive methods

Hormonal birth control methods for menstruating people are popular options for preventing pregnancy. They work by changing hormone levels in the body and simulating pregnancy in a way that blocks the occurrence of another pregnancy. They are effective and widely used

• Oral contraceptive pills: These pills contain synthetic hormones, usually a combination of estrogen and progesterone or just progesterone. They work by preventing ovulation, thickening cervical mucus to prevent sperm from reaching the egg, and changing the lining of the uterus to prevent implantation of the fertilized egg. An alternative is the progestin-only pill which is a birth control pill containing only progesterone. It is often recommended for women who cannot use estrogen;
• Contraceptive patch: This is a thin, adhesive patch containing hormones that is applied to the skin. It continuously releases hormones through the skin to prevent ovulation;
• Vaginal ring: this is a soft and flexible ring that is inserted into the vagina. It continuously releases hormones to prevent ovulation and act on cervical mucus and uterine lining;
• Contraceptive injection: This is an intramuscular injection that releases contraceptive hormones into the body. A single injection can provide contraceptive protection for several weeks or months;
• Contraceptive implant: this is a small flexible stick inserted under the skin of the arm. It slowly releases contraceptive hormones into the body over a period of years.

These hormonal birth control methods are very effective when used correctly. However, they may have potential side effects and do not protect against sexually transmitted infections (STIs).

We recommend that you consult a healthcare professional to discuss your contraceptive options and determine which method is best suited to your needs and medical situation.

Non-hormonal contraceptive methods

Non-hormonal contraceptive methods offer alternative options for preventing pregnancy without resorting to synthetic hormones. While some are particularly effective, others, such as ovulation tracking, are less reliable.

• Male condom: The male condom is a latex or polyurethane barrier that is placed on the penis before sexual intercourse to prevent direct contact between semen and the vagina. It is the only method of contraception which has the advantage of also protecting against sexually transmitted diseases (STDs);
• Female condom: The female condom is a polyurethane or nitrile sheath that is inserted into the vagina before sexual intercourse to prevent contact between semen and the cervix. Unlike the male condom, it does not protect against STDs;
• Cycle monitoring methods: This involves monitoring signs of fertility, such as basal body temperature and cervical mucus consistency, to determine fertile days and avoid unprotected sex during this period. As mentioned in this article, this method can be very reliable, however it requires good training and being rigorous in monitoring your temperature and cervical mucus;
• Diaphragm: This is a small silicone or latex dome that is inserted into the vagina to cover the cervix and prevent sperm from reaching the uterus;
• Contraceptive sponge: it is a sponge impregnated with spermicide that is inserted into the vagina before sexual intercourse to kill sperm;
• Copper IUD: The copper IUD is a small T-shaped device inserted into the uterus. Copper creates a toxic environment for sperm, preventing fertilization;
• Fallopian tube ligation : If you do not want to be pregnant, tubal ligation is a surgical operation that involves closing the fallopian tubes and thus blocking the arrival of eggs into your uterus. It is irreversible and can be difficult to obtain from doctors who do not always wish to perform it, particularly on young and childless women;
• Breastfeeding Method (Lactational Amenorrhea Method): This method is based on the fact that exclusive breastfeeding can suppress ovulation for a period of time, thus acting as a form of contraception. However, its effectiveness depends on how it is practiced. The return period being particularly fertile, do not hesitate to talk to your midwife or gynecologist before choosing it;
• Withdrawal: The withdrawal method involves removing the penis from the vagina before ejaculation to prevent sperm from entering the uterus. However, it is considered one of the least reliable contraceptive methods. Indeed, a little semen may escape from your partner's penis during penetration.

Non-hormonal contraceptive methods can vary in effectiveness and practicality. The choice of method depends on your personal preferences, medical situation, and contraceptive needs. We recommend that you consult a healthcare professional for information on which method is best suited to your situation.

Contraceptive methods for the partner

Recently, research has also focused on contraceptive methods dedicated to men in order to involve them in this process. We necessarily think here of the male condom but it is no longer the only alternative. Although the male pill is still in the testing phase, heated briefs and heating rings are now recognized contraceptive methods. This

• Heated briefs: this method is based on the fact that heat is spermicidal. The heated briefs keep the testicles against the body at a temperature of over 37°C. This has the effect of killing the sperm and thus making the sperm infertile. It is necessary to wear the briefs for 15 hours straight every day to kill all the sperm. Tests must be carried out to check that your partner's semen does not contain any sperm. Contact a health professional to implement this method;
• Contraceptive rings for men: as with heated underwear, this method is based on the fact that heat is spermicidal. However, the ring is less invasive than the heated briefs. The ring is placed around the penis and testicles and must also be worn 15 hours a day. Tests must be carried out to check that your partner's semen does not contain any sperm. Contact a health professional to implement this method;
• Vasectomy: It is a surgical procedure of male sterilization which aims to render a man incapable of producing fertile sperm and therefore prevent fertilization. During vasectomy, the vas deferens, the tubes that carry sperm from the testicles to the urethra, are cut, ligated, or blocked. This operation is not always reversible, hence the reluctance of some doctors to perform it: seek advice from a health professional .

The dangerous days of the menstrual cycle correspond to your fertile period.

If you do not want to be pregnant, these are the days when you should not have penetrative sex and vaginal ejaculation. They correspond to 5 days before the ovulatory phase until 2 days of the ovulatory phase, i.e. 7 days in total. However, because the length of menstrual cycles can change and vary from one month to the next for various reasons, the method of contraception, which consists of monitoring one's cycle without strict training and monitoring, is not 100% reliable. . If you do not want to become pregnant, it will therefore be interesting to possibly combine it with another method of contraception.