The safest days of pregnancy: how to calculate? The calendar method of protection from pregnancy: safe days

The issue of conception and pregnancy interests many people who have an active sexual life. So, some people want to quickly acquire offspring. Others think that the time has not yet come for this event. Quite often couples use the calendar method of protection from pregnancy. Safe days in this case are calculated according to a certain scheme. This is exactly what will be discussed later. The article will tell you about which days are safe from pregnancy, and also how to correctly calculate them.

Principle of conception

Before determining the days safe from pregnancy, it is necessary to learn something about fertilization. How does it usually happen?

A man with good health is almost always ready to conceive. In his body, sperm are regularly produced, which, getting into the female body, merge with the egg. When does this happen? The female cycle is divided into several parts. However, each of them can not be called fertile. So, during menstruation and after it there is a development of an estrogen. This hormone helps to grow the follicle, and also stimulates the growth of the new endometrium. A few days before the proposed ovulation, luteinizing hormone is released. It allows the follicle to burst and release the egg. Next comes the time of progesterone. This substance promotes the further transformation of the endometrium and the progression of pregnancy in the event of its onset.

After the fusion of the male and female cells, one can talk about pregnancy. However, the fetal egg should descend into the uterus and reliably there be fixed for further development.

The calendar method of protection from pregnancy. What days are considered dangerous?

The safest days (there will be no pregnancy) are the farthest from ovulation. To determine them, you need to know the dates in which sexual intercourse can lead to pregnancy.

Ovulation occurs in the female body regularly. Usually it happens once a month. Less often, the process runs twice or thrice. There is an opinion that a healthy woman ovulation may not occur about twice a year. This means that part of the cycles will not lead to conception, even during sexual intercourse on any day.

A female ovum is capable of fertilization for 12-48 hours. If the contact occurs immediately after ovulation, then there is a high probability of conception. Male cells are able to live in the body of a fairer sex for about a week. Depending on the health of the man, this period varies from 3 to 10 days. From this we can conclude that dangerous days are considered about a week before ovulation and 2-3 days after it. Let's find out which days are the safest for pregnancy. It is worth noting that much depends on the duration of the women's cycle.

In a long cycle

Safe days for pregnancy are quite easy to calculate. To do this, you just need to know the length of the female period. On a long cycle it is when its duration is 35 days. This is an absolute norm and does not require medical intervention.

The second phase of the female period lasts an average of 12 days. Sometimes this interval can be in the range of 10 to 16 days. To understand when ovulation occurs, it is necessary to perform an elementary calculation. From 35 days it is necessary to subtract the length of the second phase. As a result, it turns out 23. This indicates that it is on the 23rd day after the onset of menstruation that the follicle opens. Given the viability of male cells, we can say the following. Safe days in the long-term female period will be 1-14 days and 26-35. In total, this is 23 days.

Common cycle

What are the safe days from pregnancy in the average statistical cycle? Usually this period lasts 28 days, or four weeks. In this case, the opening of the follicular vesicle occurs on the 14th day. Remember that the duration of the second phase is always the same. Only the length of the first part of the cycle can change.

So, the egg yield occurs exactly in the middle of the month. Add to this day two days, in which the cell is able to take a sperm. The result is the following data. From 17 to 28 day, the onset of pregnancy in a woman is very unlikely. Do the same with the first part of the cycle. From the middle (the day of ovulation) take away the viability of spermatozoa. The safe period will be from 1 to 7 days. Based on this, we can conclude that the safe days in the average cycle are only about 18.

In women with a short period

What are the safe days from pregnancy in the case when a woman has a cycle of 21 days? Let's try to make a calculation.

The second phase is about 12 days. With the help of arithmetic transformations, we get that the egg leaves the ovary on the 9th day. To this day, add the life span of the female gamete. From this it turns out that the days safe from pregnancy are the period from 12 to 21 days. What can we say about the first phase? Here everything is somewhat more complicated. It is only 9 days. Spermatozoa, as already known, can wait for their hour in the female body for up to 10 days. From this it can be concluded that there are simply no safe days in the first part of the short cycle. On contact at any time, conception may occur. So, in a short cycle, the number of safe days is only one week.

Special cases

As you already know, twice a year every woman can have anovulatory cycles. During these periods, the egg simply does not come out of the ovary. Physicians say that in this case the organs of reproduction rest. Anovulatory cycles are the absolute norm. In this case, no contact will lead to pregnancy, which can occur from the first day of the cycle to its end. However, a woman can not foresee that this is the period she will have anovulatory.

It is worth mentioning separately about the cycles in the representatives of the weaker sex who are in the lactation period. During breastfeeding, ovulation does not occur. So it was considered always. However, with the development of medicine it became known that the follicles in this period still ripen. At the same time, they may be torn or undergo reverse development. Thus, during the period of breastfeeding, women's cycles are irregular. Proceeding from this, it can be concluded that it is almost impossible to calculate days that are safe from pregnancy.

Opinion of doctors

Doctors say that the calendar method of preventing unwanted conception is very unsafe. To be insured from conception, you need to have regular cycles that never fail even for 1-2 days. However, it is almost impossible.

Doctors say that safe days for women can move strongly in one direction or another. All because of the fact that the body of a representative of the weaker sex depends heavily on emotional experiences. Any event can lead to a malfunction of the hormonal output and the violation of your calculations.

Finally…

You now know how to calculate safe days from pregnancy. Remember that this method is completely unreliable. Approximately 30 women out of 100, who were protected in this way, were pregnant.