Calculating periods and the menstrual cycle calendar: how do I do it?

 

It's very common for women to wonder when their periods is going to arrive. sThis may be for a variety of reasons, such as organizing your activities around your cycle, planning a baby, or purchasing disposable or reusable sanitary protection.... So how can you reliably calculate lthe arrival of your period?

How to calculate the date of your periods ?

Knowing the day of your periods is both trivial and requires a knowledge of the different phases of the menstrual cycle ! To anticipate lthe onset of menstrual bleeding, first establish the average cycle time.

Determine the length of your menstrual cycle

A menstrual cycle starts on the 1st day of periods and ends the day before the next period.

Quite simply, subtract the date of the first day of your last menstrual period from the day before your last menstrual period. It's best to repeat the operation over your last 3 cycles to obtain the average length of your menstrual cycles.

Define your periods and pregnancy calendar

Keeping track of your menstrual periods and remembering all those dates on the calendar can be tricky! Every woman is different, with short, long, regular or irregular cycles... So it's a good idea to note down the dates of your menstrual bleeding, ovulation or any other changes each month in a small notebook or paper menstrual calendar, if you want to keep track of your monthly bleeding! Your general practitioner, gynecologist, midwife or other healthcare professional can also use an obstetrical roulette to calculate this information for pregnancy!

Use a periods

A very practical and smartphone-friendly method is to use a periods app to automatically track your periods calendar and the day of your upcoming uterine bleeding, and to better understand your symptoms throughout your cycle. There are plenty of menstrual apps on the market, so it's up to you to choose the one that suits you best, or read our comparison! They all have their own specific features, and some even go beyond simply tracking your periods, offering functions such as pill reminder,ovulation date, body temperature, ovulation calendar or pregnancy calendar... However, they all work on the same principle: all you have to do is answer a few questions about yourself and your previous cycles.

Is it possible to calculate periods with an irregular cycle?

As we've seen, the menstrual cycle is calculated by subtracting the date of the day before the last periods from the beginning of the previous ones. But how do you calculate your menstrual calendar when your cycle is particularly irregular and unpredictable?

To do this, we need to understand how the female cycle works. It is divided into three stages:

• The follicular phase (before the oocyte is released) lasts about 13 days.
• The ovulatory phase (release of the egg) lasts about 24 hours.
• The luteal phase (after release) lasts about 14 days.

In a conventional 28-day cycle, ovulation occurs on day 14, dividing the menstrual cycle in two. But in the case of a longer, shorter or irregular cycle, it's actually the follicular phase that lasts longer or shorter, while the luteal phase does not vary, lasting an average of 14 days (but can normally last between 11 and 16 days).

So, to know the day of your next menstrual flow when you have an irregular cycle, it can be useful to know how to spot your ovulation signs. All you need to do is add an average of 14 days (perhaps a little more or a little less, depending on your previous luteal phases) to this date to find out your next menstrual flow.

Signs that the ovulation period is approaching are as follows:

• Increased body temperature
• Greater production of cervical mucus, with the texture of egg white. lVaginal discharge increases as s'ovulation day approaches. Usually, when you reach the peak, you may even feel an oily sensation when wiping your vulva on the toilet. Then, from one day to the next, your secretions will suddenly diminish, and you may even feel dry. This is a sign that you've just ovulated.
• Stimulated sexual desire
• Sorebreasts or lower abdomen

All you have to do is pay attention to these symptoms and listen to your body to situate yourself in the cycle, or even use an ovulation test to confirm it if you want to get pregnant! In the meantime, to avoid unpleasant surprises, you can wear a period pants as the fateful date approaches, to be prepared for any eventuality.

When does ovulation occur during the menstrual cycle?

As we have already seen, the female rhythm is made up of 3 phases, with ovulation occurring on average around the 14th day before periods. This period corresponds to the moment when the ovary expels an oocyte, and lasts between 16 and 32 hours. Once expelled into the fallopian tubes, theegg is called the ovum. The egg is therefore the gamete ready to be potentially fertilized by a spermatozoon. In the absence of fertilization, the uterus eliminates this mucous membrane, resulting in monthly blood loss.

For women who do not have a 28-day cycle, it is possible to determine their ovulation period a posteriori by subtracting 14 days (or the value of your usual luteal phase) from the date of their last periods. If you had unprotected intercourse during this period, there's a possibility of pregnancy (it's not 100%): if you're overdue at periods, you can take a pregnancy test. You can then contact your health professional for advice.

Is it possible to ovulate twice during the same cycle?

Although very rare, it is possible for both ovaries to produce an oocyte each at the same time during the ovulation period. This is what gives rise to fraternal twins!
However, this double ovulation is simultaneous and only occurs during the same window of opportunity, at the time of the ovulation period, which lasts around 16 to 32 hours. It is therefore not possible to have an ovulation on the 14th day of the cycle and then a second ovulation several days later. Sven if there is a double ovulation, there is only oneovulatory phase per cycle!

Is it possible to get pregnant outside the ovulation period?

To put it simply: Yes, you have to differentiate between the ovulation phase and your fertile period! While ovulation lasts only 16 to 32 hours, theoocyte survives 12 to 48 hours after expulsion. Spermatozoa, on the other hand, can survive up to 5 days in the body! It is therefore possible to have fertilizing intercourse a few days before or after the actual ovulation period, thus affecting the window of fertility. Fertilization will then take place when the egg and sperm meet!

How does pregnancy affect the calculation of periods ?

Pregnancy can affect the calculation of menstrual periods in two ways, and we're going to take a look at both.

At the start of pregnancy

You've just become pregnant and are experiencing a delay periods. Pregnancy eliminates the menstrual flow, as the endometrium becomes a soft nest in which the embryo implants. There is therefore no evacuation of the uterine lining, and hence no menstruation. A delay in periods of more than a few days should therefore alert you to the possibility of pregnancy, especially if your cycle is regular!

After childbirth

You've just given birth, in which case your menstrual discharge won't return until you're back from childbirth. Immediately after giving birth, you expel blood debris and possibly placental remnants from the pregnancy, the lochia, which can last 4-6 weeks. Then, the first post-delivery menstrual periods can take place at the earliest 6-7 weeks after delivery, and more depending on whether or not you've been breast-feeding for a long time. These first periods are called the return of childbirth. The cycle will then regularize and return to your original natural rhythm.

FAQ for calculating your periods

How to calculate the arrival of your periods ?

How can I find out when my next periods is?

Does periods always arrive on the same date?

What are the dangerous days of the menstrual cycle?