Regulations 

Normal pregnancy for women. How many weeks does a normal pregnancy last after conception? Fetal movements and due date

It's not clear why people say a pregnancy lasts 9 months when it's actually 40 weeks. If it lasted a little less, it should be considered premature. Of course, it is impossible to determine the exact date of birth with certainty. Of course, it is possible to calculate the preliminary date of birth quite accurately, but it is not a fact that it will be true. Almost no one, even doctors, will be able to say with certainty how many days the pregnancy of your body lasts, and what date the birth will be. There is no single answer to the question of how many weeks pregnant women go, since this period depends on a huge number of factors. Even if you know exactly when conception occurred, you will not be able to find out how fast the sperm was, how long it implanted in the egg, how long it moved through the fallopian tubes, how long the fetus will develop in the womb. All this depends on the individual characteristics of the organism. However, there is still a small pattern of how long pregnancy lasts most often, and when the child is ready to be born. One can only rely on these calculations, but not one hundred percent hope. Certain calculations have shown that the pregnancy ends at 37-42 weeks. In the event that the 43rd week is underway, the birth is artificially induced so that there are no problems with the placenta and the child's breathing.

So, how long does a pregnancy last according to obstetricians? In most cases, women from the moment of fertilization to the onset of labor take 38 weeks, which in terms of days is 266. However, most often women do not know the exact moment of fertilization. But, most likely, they perfectly remember the date of the last menstruation. It is she who is taken for the basis of the calculation. Gynecologists say that on average, 280 days pass from the first day of menstruation to delivery. Most likely, the actual gestational age is two weeks less than the so-called menstrual period.

If you count the number of days, you can see that the period is exactly nine months, as people used to say. The average cycle lasts about 28 days, which is standard for most women. That is why a period of 40 weeks is calculated mainly for a cycle of 28 days.

How long the pregnancy lasts will be influenced by many other factors: first of all, the state of health of the expectant mother will have an important influence. Depending on what kind of lifestyle a woman led, the speed of his condition, the psychological background will depend. It also happened when a woman gave birth on a day set for herself, for example, for a holiday, or for the return of her husband from a long business trip. However, the psychological mood is not always decisive. A huge influence on how long a pregnancy lasts has a factor such as heredity. If your mom gave birth to you before your due date, chances are good that you will have the same. Almost all calculations are conditional, and trying to conceive a child in order to give birth on New Year's Eve is impossible. If, at the end of the term, you have some doubts about whether you have carried the child, you should pay attention to your well-being and the behavior of the baby.

In any case, doctors carefully monitor pregnancy and follow all recommendations. It's hard to disagree that no matter how long or hard this period is truly magical! No need to worry about trifles, you just have to enjoy your condition, because it will end pretty soon. It remains to wish only an easy birth and health to the baby!

While expecting a baby, many women wonder how many weeks the pregnancy lasts. Accurate waiting time information is needed for many purposes. With its help, you can calculate when the toxicosis ends, and the estimated moment of the birth of the baby.

Length of pregnancy in a woman

An obstetrician will help determine the gestational age at the initial stage. He examines the woman during the first visit manually and evaluates the size of the uterus to understand what gestational age it corresponds to. When setting the term, the gynecologist takes into account the first day of the last menstruation - it is believed that the uterine mucosa from this moment begins to prepare for pregnancy.

So, how many months does a normal pregnancy last from conception? Since each organism is individual, it is impossible to predict the process with an accuracy of up to a day. Medicine for this purpose uses a standard with average indicators. By generally accepted standards, the terms of bearing a child are:

  • in days – 266-280 calendar days the pregnancy lasts from the moment of fertilization to childbirth;
  • in weeks – 38-40 * weeks;
  • in months – 9 calendar months (or 10 lunar months with a 28-day cycle).

* 38 weeks - embryonic period (duration of pregnancy from the moment of fertilization to delivery); 40 weeks - obstetric period (pregnancy is calculated from the beginning of the last menstrual cycle to childbirth).

Important! The most accurate information about how long the gestation period will take from conception to childbirth is provided by ultrasound. With the help of ultrasound, the size of the uterus and the unborn baby are determined, which makes it possible to calculate the date of the onset of pregnancy and the estimated moment of the birth of the child.

What can affect the duration of pregnancy?

There are a number of factors that can affect the duration of a particular pregnancy. Some of them are beyond the competence of medicine, while others are quite predictable and are taken into account from the moment they are detected. To such factors include:

  • the state of the fetus and its intrauterine development;
  • mother's health during pregnancy;
  • psychological state of a pregnant woman;
  • heredity.

Fact! In most cases, with the timely detection of a problem, modern medicine is able to prevent complications and minimize many of the undesirable consequences.

The above factors can affect how a pregnancy proceeds, and can be the cause of both premature birth and overcarriage of the baby in the womb.

  • A premature pregnancy is one that ended in childbirth before the 37th week of pregnancy. Cases of prematurity are not uncommon, the frequency of early birth is up to 16-20% of all pregnancies.
  • The diagnosis of "postterm pregnancy" is usually made after the 42nd week of pregnancy, when the term goes beyond the third trimester. It is much less common than preterm pregnancy and accounts for only 4% of the total number of births.

Both conditions pose a threat in the form of unfavorable childbirth, and if not properly controlled, they can seriously affect not only the duration of pregnancy, but also the condition of the expectant mother and her baby.

Note!If at any stage of pregnancy a pregnant woman has an outpouring of amniotic fluid, or spotting has appeared, it is urgent to go to the maternity hospital.

Pregnancy and ovulation

Each woman can calculate the gestational age on her own if she knows the date of her ovulation. This is the only day in the month when pregnancy can occur. In rather rare cases, ovulation occurs twice for 28 days of the cycle, in which case the female cycle undergoes changes.

Calculating the day of ovulation is quite simple - you need to add exactly 14 days to the first day of the last menstrual cycle. The average female cycle lasts 28 days. It turns out that ovulation occurs just in the middle of the cycle.

If we calculate the duration of pregnancy from the day of ovulation, then it turns out that the bearing of a child lasts 266 days. This is a normal full term pregnancy. In the same way, you can predict the date of birth.

On a note! This calculation method differs from obstetric. Doctors use their own method of calculating the course of a woman's pregnancy. In medicine, lunar months with a duration of 28 days are taken into account. This period is similar to the female menstrual cycle. Therefore, according to medical calculations, pregnancy lasts almost 10 months.

Fetal movements and due date

Another factor that allows you to clarify the term of labor and the duration of pregnancy in general is the movement of the fetus.

  • In the first pregnancy, the expectant mother may feel movement at 20-22 weeks.
  • The second and subsequent pregnancies allow the pregnant woman to feel the movements of the baby at 18-20 weeks.

But each baby in the womb, as a rule, has its own specific rhythm of movement. Peak fetal activity occurs between the 28th and 37th obstetric weeks. The number of baby pushes per day can be at least twenty for 12 hours.

Important! If at the end of the second trimester the expectant mother has less than 5-7 shocks per day, this is an occasion to seek the advice of a doctor.

Second and subsequent pregnancies - differences from the first

On the forums of young mothers, you can find the opinion that the second pregnancy is somewhat faster and easier than the first. This statement has no basis, since any childbirth is an individual and unpredictable process. The sequence and number of pregnancies do not affect the duration of the specific period of expectation of the child. Labor can begin two weeks earlier or later, or when the 40th obstetric week arrives, regardless of whether the first pregnancy or not.

On a note! But the births themselves and contractions in the second or third pregnancy are short and even swift. This is a proven medical fact. Therefore, at the beginning of true contractions, it is necessary to immediately go to the maternity ward - the baby can be born at any moment.

Bearing boys and girls - are there any differences in terms?

The statement that pregnancy with a boy and pregnancy with a girl differs in terms refers to a number of folk signs. It is believed that girls are born a little ahead of time, and boys “until victorious” are waiting for the expected day of birth. In fact, this opinion has not been confirmed by modern scientific theories. Carrying a child of a certain gender can affect the internal state of the expectant mother, which is noted in some cases by fertility doctors. But the gender of the unborn baby does not affect the course and duration of pregnancy.

Expecting twins: terms of carrying a multiple pregnancy

For future parents who are expecting the birth of several babies at once, the question arises - how long does a twin pregnancy last? Determination of the duration of pregnancy is individual in nature, it cannot be calculated without the help of an ultrasound study and a weekly medical examination.

The only thing that can be said in the affirmative is that a multiple pregnancy is almost never overdue. As a rule, in a woman who carries several fetuses, childbirth occurs prematurely. This is due to overstretching of the uterus, which causes premature birth. Here, obstetricians-gynecologists have deduced a small pattern:

  • With a normal pregnancy with twins, childbirth occurs at 36-37 weeks of pregnancy.
  • If a woman is carrying triplets, delivery is likely to occur between 33 and 35 weeks of pregnancy.
  • In the case of quadruplets, the birth of children can occur at 31-33 weeks.

P.S. We will draw conclusions in video format. Here are all the stages of pregnancy by week with a detailed description of each stage:

We are used to thinking that gestation lasts 9 months. Where does the 40-42 gestational week come from? How to calculate the expected date of birth of the baby? How many weeks does pregnancy really last? Why does the timing of the birth of a baby not always coincide with the estimated date?

What affects the accuracy of calculations?

Several factors influence the correctness of the calculation:

  • knowledge of the time when the last one was;
  • knowledge of the rate of advancement of spermatozoa and the time of fusion of gametes (two germ cells);
  • knowledge of the rate of advancement of the zygote through the fallopian tubes;
  • timing of implantation;
  • information about how many times a woman bears a baby.

Most pregnant women can unambiguously decide only on the last point. Some may know the day of conception or ovulation. But the rest of the aspects will remain a mystery to both the future mother herself and the doctors. Therefore, doctors use the calculated obstetric method for determining the date of birth, which can give an error, but this error is not so significant for practical purposes.

How long does pregnancy last?

The gestational period is 10 obstetric months. An obstetric month is 28 calendar days or 4 weeks. A normal full-term pregnancy lasts 38-42 weeks. This is the average figure.

According to scientists, in 70% of 100%, 266 days or more pass from conception to childbirth. But since almost no one knows the day of conception, doctors count the period from the last day of the menstrual cycle, and not from the moment the gametes merge.

On average, the ovulation period occurs 14 days after the last day of menstruation. These 14 days are included in the obstetric period, according to which the gestation is 40-42 weeks 280-294 days. This period is usually called gestational or menstrual.

In reality, the embryo, and then the fetus will be 14 days "younger". And the real period, which is commonly called the embryonic period, will be 266-280 days from the day of conception, or a 38-40-week period.

If you recalculate the 40-week period into calendar months, you get the same cherished 9 months. According to some reports, according to modern trends, 37-43 obstetric weeks are considered the norm. If a woman in labor clears her burden within this time range, the pregnancy will be considered neither preterm nor postterm.

It must be remembered that all these calculations are correct if the menstrual cycle is 28 days.

Factors affecting the duration of gestation?

Within certain limits, the duration of normal gestation is variant, and depends on a number of points:

  • the state of the expectant mother;
  • fetal development;
  • hereditary factors;
  • psycho-emotional state of the mother.

Sometimes expectant mothers set themselves up so much for the birth of a child by a certain date that during this period they begin labor activity. There are other examples, for example, the expectant mother went to the maternity hospital ahead of time for some reason, and the cries of the ward in the ward, who had contractions, stimulated her labor activity.

There is an opinion that during the first pregnancy, especially late, women overbear children more often than with repeated gestations. According to doctors, the second birth occurs faster only if very little time has passed between periods of gestation. That is, the woman conceived before she had time to breastfeed her first child.

In other cases, the number of successful conceptions does not play a big role in the gestation period.

Mothers with multiple pregnancies carry their babies a little less. Twin pregnancies in most cases end at 32-34 weeks.

Some future mothers believe that the sex of the child affects the duration of gestation. There is no medical evidence to support this view.

preterm birth

Labor activity that began before 37 weeks of gestation is considered premature. The fetus is viable starting at 28 weeks of gestation, and the closer to full-term delivery begins, the less effort will be required from doctors to keep the baby alive.

A child born prematurely requires special conditions to maintain his life. The baby is placed in an incubator that maintains the desired body temperature, humidified oxygen is supplied, and other measures are taken to keep him alive. Preterm labor can begin for a variety of reasons:

  • ICI (insufficiency of the cervix);
  • STIs that provoked inflammatory processes in the tissues of the uterus;
  • endocrine pathologies;
  • trauma (physical and psychological).

There may be other reasons for preterm fetal failure. For example, taking certain medications.

Postterm pregnancy

If a mother carries a child for more than 294-301 days, in weeks more than 42-43 weeks, such a pregnancy is defined as post-term. Overgrowth also occurs for various reasons:

  • slow fetal development;
  • hormonal perturbations;
  • endocrine pathologies;
  • some gynecological problems;
  • unpreparedness of the psyche for childbirth.

In this case, labor activity will be stimulated artificially. Prematurity of the fetus is just as bad for its condition as early childbirth. The placenta begins to age, the baby does not receive the right amount of nutrients and oxygen. His bones are compacted, he continues to grow in a very limited space. This threatens the woman in labor with serious ruptures, and the baby with birth injuries.

If the estimated date has come, and there are no harbingers of an early resolution from the burden, there is no need to panic. The main criterion in this case is the condition of the baby and mother. If the child has stopped physical activity, the mother feels unwell, it is necessary to contact the gynecologist.

If the child is active enough, the mother feels well, but is very nervous that the birth is delayed, you can consult a specialist. He may order a fetal CTG to assess his heart rate and activity. And if necessary, send to the hospital.

To speed up the onset of labor in the last weeks before the estimated date, experts advise taking 1 tablespoon of sunflower oil, to stimulate peristalsis and reflex stimulation of the myometrium, walk more, climb stairs and have sex if there are no contraindications and there is a desire.

How long does a pregnancy last? Pregnancy lasts 280 days or 40 weeks. This is approximately 9 calendar months or 10 lunar months of 28 days. Deviations in one direction or another in 10 days are considered normal.

Usually accurate. Under such conditions, it is not age that is calculated, but age, that is, the number of days and weeks that have elapsed from the first day of the last menstruation.

The following days are taken as a guideline:

- 28 weeks is a 6-month pregnancy;

- 32 weeks-7-month pregnancy;

- 34 weeks means 7 1/2 months of pregnancy;

- 36 weeks - corresponds to an 8-month pregnancy.

Those births that occurred between 27 and 28 weeks are considered if the birth occurred after 42 weeks of pregnancy.

The probable due date is calculated as follows: the first day of the last menstruation + 10 days - 3 calendar months. For example May 15, 1983 + 10 days = May 25 - 3 months = February 25, 1984

Fetal movements

Fetal movements- This is another factor that allows you to clarify the date of birth. In a woman who gives birth for the first time, fetal movements are felt at 20-22 weeks, those who carry a second or more child hear them a little earlier - at the 18th week. At first, these movements can be confused with the work of the intestines.

Each child has their own rhythm of movement. Somewhere between 29 and 38 weeks, the movements are very active, then they subside. A normal child does at least 20 pushes in 12 hours. If there are less than 5 such movements or have completely stopped, the pregnant woman should immediately consult a doctor.

Belly sizes

Belly sizes. The fact that the belly of a pregnant woman has increased becomes noticeable somewhere after the 3rd month, however, it depends on the physique, on the amount of fluid, on the position of the fetus in the uterus and the number of previous pregnancies. Women who are carrying a child for the first time have a somewhat “pointed” stomach, after the second or third birth, the stomach sags. This shortcoming can be eliminated by special exercises, which will be discussed later. Systematic measurements of the abdomen show that at the 40th week its dimensions are approximately 100-105 cm.

When the pregnancy is already in a fairly advanced stage, the age of the fetus can be determined by measuring the height of the uterine fundus.

- At the 24th week of pregnancy, the bottom of the uterus reaches the umbilical cavity;

- At the 36th week, the bottom of the uterus reaches the lower end of the costal arch;

- At the 40th week, it is at the same distance from the navel and the lower end of the sternum.

So, it reaches its highest level 4 weeks before delivery. The fetus descends in the 9th month, and the size of the abdomen seems to be slightly smaller.

When the fetal head descends into the small pelvis, the bottom of the uterus also descends. During the first pregnancy, this happens three weeks before, during subsequent pregnancies, the stomach drops only at the beginning of labor - the woman in labor feels a little pain. But it becomes easier for her to breathe, her stomach no longer “supports”. And there is also a feeling of embossing in the pelvis, it becomes more difficult to walk, more urine passes.

Is it possible to say in advance what kind of childbirth will be? The obstetrician can only find out if the pelvis is normal, there is no anomaly of the genital tract, and the child lies correctly. But no one knows in advance what kind of contractions the mother will have. If the uterus contracts vigorously, childbirth is accompanied by powerful contractions, then everything will be fine. It can even pass through a medium-sized pelvis without harm to itself and the mother.


The question is both simple and complex at the same time. Everyone knows that pregnancy lasts about 9 months. But for a future mother, such an answer is not enough. I would like to calculate exactly on what dates the baby will be born, who he will be according to the sign of the zodiac, when the prenatal sick leave begins. There are frequent situations when childbirth occurs earlier or, conversely, later than the scheduled date. What factors affect the duration of pregnancy, from what gestational age the child is already viable, what is the danger of overbearing - we will talk about all this in our article.

Within the norm:

It is difficult to say exactly how long the pregnancy lasts. It is impossible to establish the true date of ovulation, the time of movement of the sperm to the egg and their fusion. Therefore, in the medical literature there are conflicting data on this issue. A fully mature healthy baby can be born through 230-240 days after fertilization . At the same time, there are cases when the gestation period is significantly lengthened - over 300 days or more. But most often it is 10 obstetric months (28 days each), or 280 days (if counted from the first day of the last menstrual bleeding).

The entire gestation period is conditionally divided into 3 trimesters. The first trimester of pregnancy lasts until 12-14 weeks, the second - from 14 to 24-28 weeks, and the third - from 24-28 weeks before delivery. If the fetus is born before 24 weeks, this is considered a late miscarriage. A baby born between 24 and 27 weeks is premature. A pregnancy that lasts longer than 42 weeks is considered post-term and the newborn is post-term.

When to give birth?:

It is almost impossible to predict this exactly, since pregnancy does not always occur on the day of sexual contact, but it can occur after 48-72 hours. However, with the help of history taking, internal obstetric examination and ultrasound, the estimated date of delivery for each pregnant woman is determined.

For example, knowing the date of the first day of the last menstruation, and assuming that the pregnancy will last 280 days: add 7 days to this date and subtract 3 months. So, if the date of the beginning of the last menstruation is January 10, then the birth will presumably take place on October 17. If the date of ovulation is known (you measured the basal temperature or performed special tests), then 266 days are added to it.  

When the cycle is not regular, it is difficult to remember the date of the last menstruation or it was not there at all, since you are breastfeeding, the ultrasound is used to judge how long the pregnancy will last. The earlier it takes place, the smaller the error. Usually it is 7-8%, in the I trimester - 1 week, in the II - 2 weeks, in the III - 3. To reduce the error to 3-5 days, during the ultrasound screening of the I trimester, they are guided by the vertical size of the embryo (from the coccyx to crown).
The duration of the current pregnancy can be judged by fixing the date of the onset of sensations of fetal movement. For women who are carrying a child for the first time, 22 weeks are added to this date, and 24 weeks again. It also helps in determining the size of the uterus at the first visit to the antenatal clinic (the error will be smaller if this is done before 12 weeks). These techniques are additional, as well as external obstetric changes.  

All these data complement each other. But it should be remembered that they are focused on the average pregnancy, lasting 40 weeks (280 days). Given this, the reduction or extension of pregnancy by 2 weeks is not considered a pathology.

About rewiring:

It is legitimate to talk about overstaying a pregnancy when it lasts more than 42 weeks, or 294 days, from the date of the start of the last menstruation. This is a fairly common phenomenon, occurring in 4-9% of cases. Why is this condition dangerous? Likely fetal macrosomia, oligohydramnios, meconium ingestion, antenatal fetal death and the development of the syndrome of "overmaturity" of the newborn. For the mother, this is fraught with an increase in the frequency of operative abdominal delivery. In practice, it is confirmed that the risk of these complications already at a period of more than 40-41 weeks is much higher.

In establishing this diagnosis, the main role is played by the exact determination of the gestational age. If this is not done correctly, then the fact of overwearing is called into question. What factors can prolong pregnancy? Nobody knows for sure. The most likely are: a decrease in the level of estrogen in a woman, on the part of the fetus - underdevelopment of the adrenal glands, angiophysiology, anencephaly. Medical tactics: hospitalization, observation of the reaction to a non-stress test, assessment of the condition of the fetus, the amount of amniotic fluid, stimulation of labor at 41-42 weeks.

Prematurity: causes and prognosis:

When regular contractions occur in the period from 24 (28) to 37 weeks, which lead to the beginning of the opening of the cervix, they speak of premature birth. Frequency - up to 15% of cases. We hasten to reassure you: many women experience periodic uterine contractions, but only those that cause the smoothing of her neck and disclosure can provoke childbirth. It happens that painless gradual disclosure is not accompanied by contractions - this is isthmic-cervical insufficiency.
Premature birth is a major factor in the loss of a child. The cause of death is the immaturity of the lung tissue, intraventricular hemorrhage, necrotizing colitis, etc. The survival rate is directly proportional to gestational age. At birth, 50% of babies survive at 24 weeks, and 99% at 36 weeks.

Why can the duration of pregnancy decrease? There are many reasons: rupture of the fetal bladder or detachment of the placenta, multiple pregnancy, chorioamnionitis, bicornuate uterus, genetic predisposition. Smoking, low body weight, history of abortion, frequent childbirth are premorbid background for this pathology.

Medical tactics: hospitalization, bed rest, complete examination, monitoring of the fetal heartbeat and contractions, laboratory and ultrasound examination, the possibility of tocolysis is assessed. The determination of fetal fibronectin in cervical mucus "speaks" of a high probability of the onset of labor in the coming week. To accelerate the maturation of the child's lungs, a woman is urgently prescribed glucocorticosteroids. This increases his chances of survival.

How long does a boy and girl pregnancy last?:

Among expectant mothers, it is very common to believe that a boy's pregnancy lasts longer. We consider it necessary to debunk this myth. The gestation period is completely independent of the sex of the fetus. The formation of the genital organs begins from the 4th week of embryonic development, they become clearly visible from 12-16 weeks, at 20 weeks they are already clearly marked. The further development of the boy and the girl is exactly the same.  

How long is the second pregnancy?:

The theory that the second pregnancy is shorter than the first is also not confirmed in practice. There are no physiological prerequisites for the second child to require less time for intrauterine development. But the fact that the period of contractions during the second birth is shorter, and the opening of the cervix is ​​faster, is true. In a woman giving birth, the birth canal is more elastic and pliable, so it takes less time to form the lower segment of the uterus and open its cervix. The period of contractions is on average reduced to 6-8 hours.