Symptoms during implantation of the fertilized egg. Signs of embryo implantation

The most significant transformations of the fetus occur on early stages pregnancy. Within a few days from the moment of conception, it turns from one cell - a zygote - into a millimeter-sized embryo. The formation of the fertilized egg begins immediately after the fusion of the sperm and egg into fallopian tube. After this, the fertilized egg attaches to the wall of the uterus. Is it possible to feel the moment of implantation of an embryo into a woman’s body?

How does conception occur?

In order for conception to occur, the participation of two gametes is necessary - a sperm and an egg. In the first half menstrual cycle The oocyte matures - under the influence of the gonadotropin FSH, it is formed in the ovarian follicle. Around the middle of the cycle, usually on the 14th day, dominant follicle ruptures and a mature egg emerges. This phenomenon is called ovulation.

After leaving the ovarian follicle, the egg travels into the fallopian tube. If sexual intercourse occurred on this day or 2-3 days before, then some of the sperm could reach the fallopian tube. It's there male gametes waiting for the female to merge with her and fertilize her.

If there are no sperm in the oviduct, the egg continues its movement, descends into the uterus, dies and comes out along with menstrual blood. If male gametes are present, then they all together begin to attack the surface shell of the egg - the corona radiata. One sperm cannot destroy it; the effort of several is required. However, only the one who first manages to reach the inner layer - the zona pellucida - fertilizes the oocyte.

Zygote implantation during natural conception and IVF

As a result of the fusion of a sperm and an egg, a zygote is formed. This is the one-cell stage of the embryo's existence, which lasts 26–30 hours. Then, as a result of mitotic division, the zygote begins to fragment. By the 4th day of pregnancy, the embryo consists of 12–16 cells, and by the 5th day it already consists of 30. At this stage of development, it is called a blastocyst.

At what time does the blastocyst attach to the uterine wall? During the first 5–6 days, the embryo moves along the fallopian tube and descends into the uterine cavity. During this time, progesterone, which is secreted by the corpus luteum, manages to prepare the endometrium of the uterus for implantation of the fertilized egg - it becomes more loose. The cells of the surface layer of the blastocyst - the trophoblast - throw out finger-like processes and cling to the endometrium. This is how the embryo is implanted.

Implantation at in vitro fertilization is carried out differently and is most often late. The transfer of a fertilized egg is done 3 or 5 days after the fusion of gametes. Due to this late transfer, the process of implantation of the blastocyst into the uterine wall is delayed. That is why, after the transfer of IVF embryos, late implantation of the embryo occurs. In this case, there are usually no symptoms such as spotting or implantation bleeding.

How to understand that the embryo has attached to the wall of the uterus?

Are there certain signs of implantation of the fertilized egg into the endometrium? Despite the fact that this stage of gestation may be asymptomatic, some women, based on certain signs, can determine that they are pregnant even before their period is missed. The process of embryo implantation is accompanied by the following symptoms:

bloody discharge;
nagging pain in the lower abdomen;
change in basal temperature.

Bloody discharge not of a menstrual nature

Approximately 7 days after unprotected intimate contact, a woman notices spotting red-brown discharge on linen. Even before the delay of menstruation, this symptom indicates that fertilization has occurred and the implantation of the blastocyst has been successful.

The nature of the discharge during embryo implantation:

scanty, spotting bleeding;
last no more than 48 hours;
color of varying intensity - from pink to brown;
There is no unpleasant odor.

Why is the attachment of the embryo to the uterus accompanied by bloody smears? This is due to the fact that during the implantation of the blastocyst into surface layer the uterus, the smallest capillaries of the endometrium are injured. There is no need to worry, microtraumas heal very quickly.

Not all women experience implantation bleeding, but this does not mean that implantation of the fertilized egg did not take place. Women who have gone through the IVF procedure eagerly await these signs, but ultrasound diagnostics can more accurately determine whether the embryo has taken root.

Basal temperature

Another symptom of implantation of the fertilized egg is changes in basal temperature. Basal is the temperature of the body in a state of complete calm. It can be used to track ovulation. Basal temperature is measured immediately after waking up; women are advised to keep the thermometer by the bed so as not to get out of bed to get it. At the moment the value increases by 0.2–0.4 degrees, a woman ovulates, this is the most favorable period for sexual intercourse if the couple has a desire to conceive a child.

The same changes occur at the time of implantation of a fertilized egg into the endometrium. The thermometer readings are 37.0–37.3°C. Typically, a woman does not feel unwell, as with a fever during a cold, because the body temperature quickly returns to normal.

Nausea, weakness, nagging pain in the lower abdomen

Some women have very high sensitivity. They feel the moment the follicle ruptures, when the egg comes out of it, and they feel the separation of the endometrial elements. It’s the same with the attachment of the blastocyst - expectant mother physically feels how this happens.

Similar sensations during embryo implantation can manifest themselves in the form of aching, nagging pain in the lower abdomen, closer to the pubis. Some people note that they begin to pull in the lower back on the sides.

Usually toxicosis appears later, but despite the fact that there are general norms the course of gestation, each woman’s pregnancy has its own individual characteristics. That is why, immediately after fertilization, a pregnant woman will feel weak, drowsy, and lethargic. Some people begin to feel sick in the morning, and their taste preferences change.

Mood swings

With the onset of pregnancy, the hormonal levels in a woman's body change. After ovulation, progesterone begins to enter the blood, the concentration of which does not decrease after 2 weeks, as during the normal menstrual cycle, but continues to increase. After implantation of the embryo, the chorion begins to produce human chorionic gonadotropin. Hormones influence all systems of the body, including the central nervous system, which affects emotional state women.

In the morning the pregnant woman is joyful and high mood, which without visible reasons gives way to anger and irritability, and towards evening she becomes whiny and sad. Such sudden mood changes can accompany a woman throughout her entire gestation, but may also go away after she adapts to her new state.

When will the pregnancy test show?

All existing pregnancy tests react to the content of hCG in the urine, which begins to be secreted only after the implantation of the fertilized egg. Previously, it is pointless to conduct home tests; they will give false results.

How long is it better to wait before the test and on what day can it be done? A week after unprotected coitus It is too early to do the test, because the concentration of hCG will not be sufficient to be detected by the reagents. Depending on the type of test, it should be done 2-3 days before the expected delay or immediately after it.

There are several types of pregnancy tests:

Stripes. The cheapest and most accessible test, at the same time it is one of the most unreliable. However, this does not mean that the strip gives false results; the probability of error is only 4–5%. He has low sensitivity In order for the strip to detect hCG in the urine, the hormone concentration must be at least 20 mIU/ml, which is achieved 2–3 weeks after sexual intercourse.
Tablets. This test consists of a cassette with a urinal hole and a window on which the results are displayed, and a pipette for collecting urine. This analysis is close to laboratory ones and detects the hormone at a concentration of 15 mIU/ml.
Electronic device. Considered the most precise method pregnancy testing at home. Susceptibility – 10–15 mIU/ml. It is allowed to carry out the analysis 10 days after intimate contact, but the more time passes between coitus and the test, the higher its accuracy.

Why might an embryo fail to implant in the uterus?

Some women encounter a problem when fertilization itself occurs successfully, but the embryo cannot consolidate in the uterus and is brought out. Reasons why the embryo does not attach:

Hormonal imbalance. For attachment to be successful, it must be developed sufficient quantity progesterone. It prepares the uterus to receive the baby, reduces immune reaction on a foreign organism so that the mother’s body does not reject the embryo. When there is not enough progesterone, conditions for attachment are not created, and the embryo comes out. The cause may be insufficiency of the corpus luteum or its absence. Similar condition treated with medications hormone therapy, for example Utrozhestan or Duphaston.
Endometrial changes. It happens that the embryo simply cannot be found suitable place, to gain a foothold in the uterus, because the surface of the endometrium is covered with scars. This condition of the endometrium can be a consequence of abortion with curettage, surgery on the uterus, inflammatory, infectious diseases. Late implantation at the os of the uterus can be a consequence of such pathologies.
Tumor processes. New growths in the uterus - polyps, fibroids, fibroids - prevent the blastocyst from gaining a foothold in the cavity.
Genetic abnormalities. Due to mutations in germ cells during fertilization, a non-viable zygote is formed. For example, two sperm get inside at the same time, or one of the gametes does not carry genetic information. Such an embryo does not develop, cannot attach, and miscarriage occurs before its implantation.

After the IVF procedure, doctors carefully monitor whether the embryos have taken root. At this stage of medical development, not all embryos take root, so patients undergo artificial insemination again.

Often, pre-implantation miscarriages are asymptomatic and the woman may not realize she was pregnant. Typically, such patients turn to gynecologists with the problem of infertility, not knowing that the problem is not conception, but the ability to implant. The doctor can help solve the problem by choosing suitable method treatment.

The fertilized egg is a ball consisting of many cells and having two layers: internal (embryoblast) and external (trophoblast). Around the nineteenth - twentieth day of the menstrual cycle, the fertilized egg attaches to the decidua (endometrium of the uterus).

On the twenty-first to twenty-fourth day of the cycle, the fertilized egg comes into contact with the loosened wall of the uterus. Outgrowths called villi are formed in the trophoblast, with their help it penetrates into the uterine cavity and is fixed.

At the point of contact, a section of the uterine wall melts, and the fertilized egg passes deep into it. During this process, the integrity of the capillary vessels is disrupted, and the blood contained in them comes out. A woman might notice minor bleeding, which do not pose any danger.

After the egg is fixed, its active production of the hormone hCG (chorionic gonadotropin) begins, which signals the entire body about the onset. When it reaches a certain level, the test reacts positively.

Gradually, the tissue defect at the implantation site is closed with a fibrinous plug, and the lining of the uterine wall is completely restored. The fertilized egg is immured inside the uterine wall.

Location of the fertilized egg in the uterus

The fertilized egg is implanted into various places uterus. It depends on various circumstances. Its most favorable location is in the fundus of the uterus, but often this occurs on the back or front wall.

In the case when the fertilized egg is attached very much in the fundus of the uterus, and as pregnancy progresses the placenta becomes higher and higher, it is necessary to limit physical activity. During this time, the doctor must carefully monitor the woman’s condition, as there is a possibility premature detachment placenta with subsequent bleeding, and as a result - hypoxia.

Very great value during implantation of the fertilized egg, the uterine mucosa is ready for this process. If a woman had, IUDs were used as contraceptives ( intrauterine device), took place infectious diseases– the mucous membrane is poorly prepared for pregnancy, and therefore implantation may occur either abnormally or not occur at all.

Tip 2: Implantation of the embryo into the uterus. What happens after fertilization.

After the fusion of male and female germ cells, the resulting cell is actively fragmented, moving towards the uterus. Once in the uterus, it prepares to be introduced into its wall - implantation. The implantation process is necessary to organize the exchange of nutrients between the future fetus and the mother.

Movement towards the uterus and preparations for the implantation process

The cell resulting from the fusion of an egg and a sperm is called a zygote. Fusion occurs in the fallopian tube. Immediately after formation, the zygote begins the process of crushing. This process occurs in geometric progression, and after 96 hours, 16-32 fragments - blastomeres - appear. In this case, the zygote resembles a raspberry or blackberry fruit and is called a morula. At this stage, it penetrates the uterus. Until the moment of penetration, it moves along the fallopian tube. The zygote cannot move independently; contractions of the fallopian tube contribute to this. These contractions occur under the influence of sex hormones, estrogen and progesterone.

When entering the uterus, one part of the blastomeres forms an embryoblast, from which the embryo itself will subsequently develop. Other blastomeres form the nutritional membrane for the embryo, while others will become the placenta. The zygote approaches the site of implantation, which is the anterior or posterior wall of the uterus. By the time of implantation, the endometrium - the lining of the uterus - changes. The mucous membrane enters the secretory phase, the secretion of its glands contains compounds necessary for the life of the embryo.

Embryonic implantation and early development

The process of zygote implantation itself is largely mediated by the influence of sex hormones. During pregnancy, the so-called corpus luteum appears at the site of the burst follicle, from which a mature egg emerged. It begins to actively grow and function, secreting progesterone and estrogen. These hormones affect the lining of the uterus and contribute to its transformation. Some scientists even regard the changed uterine endometrium as a semblance of independent endocrine organ. This is due to the fact that it actively produces the hormone prolactin.

Implantation of the zygote into the uterine wall lasts approximately two days. If it is completed successfully, the hormone human chorionic gonadotropin begins to be actively synthesized. Around the implantation site, the blood vessels dilate, forming sinusoids. Thus, the beginning of metabolism between the mother’s body and the embryo is laid. Next, the placenta and umbilical cord are formed. After this, the rudiments of the organs and systems of the unborn child begin to form, and one of the first to begin to develop is nervous system. By the end of the first month already

Fertilization of the egg is one of the main, but far from last stages when a woman becomes pregnant. Much more significant is the stage of embryo implantation, i.e. its attachment in the uterine cavity.

Next, you are invited to familiarize yourself with basic information regarding the process of embryo consolidation, the average time frame during which this process occurs after ovulation and at other stages of the cycle, possible deviations And additional features implantation of a fertilized egg during the procedure of artificial (in vitro) fertilization.

Basic information about the embryo implantation process

As you know, fertilization occurs when the fastest and most active male sperm reaches the female egg. Immediately after this, a membrane appears on the surface of the latter, preventing other sperm from penetrating inside. This “shell” remains on the surface of the fertilized cell until it reaches the uterine cavity.

In the process of “travelling” to its “destination”, the embryo continuously divides, during which an increasing number of cells are formed. The embryo moves up the fallopian tubes to the uterus - the villi located on the uterus help it in this. fallopian tubes ah and the contractions of the latter: the embryo rolls around like a ball.

Upon arrival at uterine epithelium, the fertilized egg loses its protective membrane, resulting in exposure of the trophoblast, through which the embryo attaches to the inner wall of the uterus. The trophoblast will retain its important function and in the future - it will take part in the formation of the placenta.

This is what the process of embryo implantation looks like ideally. However, in some cases there are various kinds negative factors, preventing the successful fixation of the embryo in the uterine cavity. For example, if the upper membrane is too thick, the embryo may not implant. This is one of the forms of natural selection: only a genetically complete and healthy embryo has a chance of survival.

Problems with embryo implantation can also arise for other reasons, among which the following factors are most often noted:

excessively thick top shell fertilized egg;
dysfunction of the blastocyst, which is predominantly genetic in nature;
inappropriate epithelial thickness internal cavity uterus;
deficiency of progesterone in the maternal body (under the influence of this hormone, among other things, conditions are created for the implantation of a fertilized egg and the subsequent development of the embryo);
lack of nutrients directly in the tissues of the uterus.

The successful consolidation of the embryo is indicated by an increase in the concentration of hCG in the maternal body and a number of other signs, which will be discussed separately below. Now you are invited to familiarize yourself with information regarding the average time for embryo consolidation.

HCG at multiple pregnancy after IVF

Average embryo implantation time

On average, it takes about 1 week for a fertilized egg to “travel” to the uterus. In general, the duration of this process depends on the state of the embryo and its viability, the function of the fallopian tubes, the hormonal system in the mother’s body and a number of other factors.

Based on average data medical research, the attachment of the fertilized egg to the epithelium of the uterus occurs in the period from 6 to 12 days after ovulation. This often happens a few days before the next menstruation.

Directly on the process of embryo implantation, i.e. implantation of the blastocyst into inner wall uterus, it may take from a couple of hours to 2-3 days. Average term equals approximately 40 hours. During this time, the trophoblast of the fetal egg penetrates into the tissue inner surface uterus and takes root in the mother's body. In this case, the implantation process may either pause or proceed with greater activity, which is why signs of embryo implantation may also be episodic.

Implantation probability chart by days after fertilization

Days after fertilization	Probability
5-6 dpo	2%
7 dpo	5.56%
8 dpo	18.06%
9 dpo	36.81%
10 dpo	27.78%
11 dpo	6.94%
12 dpo	2.78%

It is the process of implantation that is most significant for the developing embryo. If the embryo is successfully fixed, it is highly likely that it will be able to cope with other difficulties. If the embryo is sick and weak, the woman’s body may reject it even at this stage of pregnancy.

Depending on individual characteristics female body, implantation of the fertilized egg can be late or early. Information regarding these points is given in the following table.

Table. Early and late dates implantation

For it to happen successful implantation embryo, the following conditions must be met:

thickness of the uterine mucosa – up to 1.3 cm;
nutrient concentration is normal;
progesterone content is sufficient to delay menstruation and ensure further full development of the fetus.

As a rule, most women have some serious changes well-being does not occur during implantation, but the possibility of their occurrence cannot be ruled out either. The main thing is to objectively assess changes in well-being and not try to mentally multiply them in anticipation of fertilization.

Among the most common signs of embryo fixation in the uterus, the following signals can be noted:

Above, in the list of signals of embryo consolidation, such a sign as implantation bleeding was given, in most cases it manifests itself in a few drops of blood on underwear. In some patients the situation may be more aggravated. So, if the patient experiences unpleasant pulling sensations in the lower abdomen, accompanied by bloody discharge, she definitely needs to see a doctor. A similar reaction of the body can be provoked by various types of gynecological and diseases and infections of the genitourinary tract.

Uninformed women often confuse this pathological condition with implantation bleeding, which is one of the normal variants. It is very important to be able to distinguish between them and promptly respond to such unfavorable changes in the state of the body.

So, when the embryo is implanted, the secretions have normal look, they just contain quite a bit of bloody inclusions. If your discharge differs from that described, consult a specialist immediately.

Features of embryo implantation during in vitro fertilization

Currently, the only opportunity to become parents for everyone is more couples is in vitro fertilization. The issue of embryo implantation after this procedure deserves special attention.

In general, there are no serious differences between the process under consideration and embryo attachment during natural pregnancy no: everything happens according to a similar scenario; after the procedure, a woman may experience some characteristic sensations etc.

But distinctive features during the implantation process artificial insemination still there is. So, if conception was not carried out in the mother’s body, the implanted embryo may need some time to get used to its new conditions. It is because of this that it is not always (on average only 30-35% of cases) that women manage to get pregnant immediately after the in vitro fertilization procedure.

If a fertilized egg does implant, the first signs of this usually appear later than during natural conception. In order to reduce the likelihood of miscarriage, the expectant mother should take some precautions, namely:

get enough sleep and rest in general;
avoid excessive physical activity;
eliminate stressful situations;
temporarily (until permitted by a doctor) exclude sexual intercourse;
don't take too much hot bath and shower;
do not overcool or overheat;
maintain a healthy and balanced diet;
walk outside more often;
minimize any harmful effects on the body;
avoid visiting crowded places;
do not contact sick people.

For the sake of their own safety and in order to minimize risks to the embryo, a woman after IVF is recommended to even refrain from managing vehicles and riding on public transport.

In general, doctors recommend following special measures precautions until the 20th week of pregnancy - by this period the placenta usually has time to fully form and the fetus becomes more protected than before. For example, from an obstetric point of view, it is up to this point that the implantation procedure occurs, after which the baby enters the active stage of growth. But this does not mean that after the 20th week you can begin to treat yourself and the fetus lightly: precautions and doctor’s recommendations must be followed throughout the entire period.

Health to you and your baby!

So the greatest of miracles happened - the birth of a new life. The egg left the ovary and entered the lumen of the fallopian tube. Here she meets sperm that have managed to overcome the distance from the cervix. Fertilization is not such a simple process.

The egg is covered with a fairly dense membrane, so it will be possible to penetrate it immediately. Spermatozoa secrete special substances that dissolve the protein of the membranes and unwind the cell with their flagella. Gradually, its cover becomes thinner and one lucky person penetrates inside, giving rise to a new life.

What happens after the egg is fertilized?

A day after fusion with the sperm, active fragmentation of the fertilized egg begins. At first it happens synchronously. The cell first divides into two, after 12 hours into 4. Thus, after 96 hours the embryo already has 16 or 32 cells. The first days of its life it resembles a raspberry and is called a morula, and on the 3-4th day it forms a ball called a blastocyst.

In parallel with growth, the cell moves towards the uterus. She cannot move on her own, but is transported under the influence of contractions of the fallopian tube, movements of the epithelium and the flow of fluid in the capillaries. The advancement of the embryo is regulated by hormones.

After the release of the egg from the ovary, a special temporary organ is formed in its place - corpus luteum. It produces progesterone and estrogens. These hormones ensure the correct speed of embryo advancement. At first, the level of progesterone is low, so the cell lingers at the very beginning of the fallopian tube, where fertilization and the beginning of division occur. Then its quantity increases, so contractile function fallopian tubes grow and become peristaltic in nature. That is, they contract in waves directed towards the uterus, and thus “drive” the fertilized egg forward.

Only a certain ratio of progesterone and estrogens, as well as some other hormones in the blood, can guarantee the correct and timely advancement of the embryo into the uterine cavity.

The journey from the ovary to the uterus takes about four days for the unborn baby. After this, one of the most important and complex processes in his intrauterine life begins - implantation.

Features of fertilized egg implantation

Implantation is a very complex process that requires coordinated work embryo and maternal body. If it is not there, implantation may not occur. Most often this happens if the embryo has very serious genetic defects.

A healthy embryo, on its way to the uterus, begins to accumulate substances in its body that can dissolve its endometrium. At the same time, villi grow on it, through which the embryo will receive nutrients. Mom's body is also preparing for implantation. Under the influence of the hormone progesterone, the structure of the endometrium takes on a form favorable for the implantation of the embryo.

How and when does implantation occur?

The implantation of the embryo in the uterus usually begins on the fourth day after fertilization, which is approximately 5 days after ovulation. It takes place in three stages

Accession. Once in the uterus, the fertilized egg immediately clings to its mucous membrane. After this, the uterus is filled with a special fluid, which lifts the embryo, pressing it to the endometrium.
Sticking (adhesion). The fertilized egg has already joined the epithelium and now its microvilli actively interact with its cells.
Invasion and nesting (invasion). The embryo breaks down the lining of the uterus, connects with maternal blood vessels and forms an embryonic kidney.

Symptoms and signs of implantation

For most women, their well-being does not change in any way during implantation. This process occurs almost painlessly, and changes in hormonal levels do not yet manifest themselves externally. But sometimes women who closely monitor their health may notice some symptoms:

Implantation bleeding. Invading the wall of the uterus, the fertilized egg causes minor damage blood vessels. Because of this, the discharge may take on a brownish or pink tint.
Tingling or pulling sensations in the lower abdomen. They can be very weak or quite noticeable. They are usually localized at the site of egg attachment.
. A slight inflammation occurs at the site of embryo implantation. Because of this, not only basal, but also body temperature may increase.
Implantation retraction is a short-term decrease in basal temperature by 1-1.5 degrees before its increase during the implantation period.
Mild malaise, nausea, apathy, metallic taste in the mouth.
Emotional instability. During this period, women often experience mood changes due to changes in hormonal levels. May appear increased need in care, tearfulness and self-pity.

Discharge during implantation of the fertilized egg

Implantation bleeding is a symptom that requires more detailed consideration. The fact is that it is not easy to recognize it. It does not happen to all women; it can be very scanty or even heavy, like menstruation. Its duration also varies - usually it is 1-2 days, but it can be longer. Therefore, many women with irregular cycle They mistake such discharge for regular menstruation and do not notice their interesting situation.

Normally, implantation discharge is very scanty, spotting, and lasts no more than 2 days.

If you are planning a pregnancy and are monitoring basal temperature, then its changes will indicate that this is implantation. But remember that similar symptoms may be with some gynecological diseases. Therefore, if the discharge is too strong and/or accompanied by other unpleasant symptoms, it's better to go to the doctor.

Conceiving a new life is considered a complex manipulation. Initially, an egg is formed, then it matures, is fertilized, and is fixed. The task of the sperm is to reach the finished egg. All these processes occur under certain conditions. When there are problems with the ovaries, the readiness of the egg will be impaired. If sperm are not active enough, fertilization will not occur. Implantation of the fertilized egg into the uterus is possible with excellent tubal patency.

Peculiarities

Implantation in gynecology is the introduction of an embryo into the uterus. Pregnancy often occurs between 7 and 10 DPO (days after fertilization). At positive result Providing the fetus with everything necessary will pass through the organs of the expectant mother.

Implantation is the onset of pregnancy. The young mother hardly feels it, but this step is very important for the subsequent development of the embryo. The fetus will not turn into an embryo without this manipulation.

Implantation takes place in three stages:

accession. The egg clings to the queen as soon as it reaches her. After this, it is filled with fluid, which lifts the embryo to the endometrium;
adhesion. The villi of the egg actively contact the epithelial cells;
invasion. An embryonic bud is formed.

The coordinated interaction of the mother’s body and the fetus contributes to a positive outcome of the operation from pregnancy to childbirth.

Is it possible to feel the implantation of the fertilized egg? No. Often it goes unnoticed. The female representative does not hear everything that happens in the body. The first sensations come later.

Where is the fertilized egg attached? The place of attachment varies, depending on various circumstances. However, most often the connection is made to the front or back wall uterus.

When does the fertilized egg attach to the wall of the uterus? The period of division and movement takes a week. The egg reaches the uterus. Within 2–3 days after fertilization, implantation of the fertilized egg occurs.

The course of the implantation process

The implantation period of the fertilized egg lasts approximately 40 hours. The only symptom indicating the moment of attachment is scanty bleeding.

Pregnancy occurs 3–4 days after sexual intercourse. Thus, fertilization and implantation of the fertilized egg are determined by day. From this time on it begins to form certain hormone: HCG, tests react to it, showing the period of implantation of the fertilized egg in the uterus, determining the onset of conception.

The birth of a new life occurs as follows:

the egg is fertilized and begins to move in the uterus;
during movement it divides, the number of cells doubles;
outwardly it looks like a blackberry-type berry, with many grains;
movement inside the uterus continues for up to three days;
then the same amount of time is needed for her to move towards the implantation zone; the fertilized egg attaches to the uterus.

Having found a position convenient for itself, it transforms into a blastocyst. Its penetration into the wall of the uterus is implantation during pregnancy. This happens on the 7th day.

When a week passes after implantation, the result is large, determine it using this test easily. The cervix plays an invaluable role in gestation. It ensures that the fertilized egg is kept in its proper place.

Symptoms, signs

The attachment of the fertilized egg does not cause changes in well-being in most women. The process occurs without pain. Hormonal background does not change externally. However, a female representative who carefully monitors her health is able to notice changes.

Symptoms of implantation:

bleeding. The introduction of an egg into the uterus slightly damages the blood vessels. As a result, the discharge acquires a pinkish tint;
There is a tingling sensation in the lower abdomen. In its manifestation it is not strong, slightly sensitive. The focus of its localization is where the egg is attached;
temperature rise. It is associated with the appearance of slight inflammation in the area of implantation. Sometimes this phenomenon is perceived as cystitis during embryo implantation;
Before the increase, the temperature may drop by a degree to one and a half. This phenomenon is noted as short-term;
When the embryo is implanted, dizziness, slight malaise appears, apathy and indifference to everything that happens around occurs.

Emotional instability often sets in. The state of health during embryo implantation can be characterized by mood swings. Tears, self-pity, and the need for excessive care appear.

The above listed signs are weak and specific. For some women, they go completely unnoticed.

Behavior during the implantation period. A woman planning to conceive a child considers it natural to reduce physical activity, even to the point of abandoning it completely. She switches to bed rest, providing the embryo with the opportunity to quietly attach to the wall of the uterus. However, such a judgment is incorrect. The restrictions apply to female representatives who have undergone fertilization using artificial methods. The rest can continue familiar image life without fear.

Pregnancy maintenance is affected genetic factors, readiness of the endometrium to accept the embryo, presence or absence chromosomal abnormalities. Therefore, bed rest is not at all necessary. A patient who has undergone IVF is given a certificate of release from work for 7 days. However, this does not negate her full ability to work. This measure is a kind of insurance.

Conditions for a successful operation

The egg successfully ovulated. The sperm overtake her and begin to attack. When the most active one manages to fertilize the egg, it divides into two parts, turning into a zygote. Further division continues until 32 paired chromosomes, the moment of formation of the blastocyst. All these processes take up to 7 days. The fertilized egg, after 3 days, reaches its target: it attaches to the membrane. From that time on, she becomes a fetus, growing and developing inside the mother.

Highest probability implantation by day falls 8 - 10 after ovulation, it is associated with mobility, life expectancy of the egg, sperm. We can say with confidence that this determines how many days the implantation of the fertilized egg occurs after fertilization.

For the implantation process to be effective, certain conditions must be present:

endometrial thickness;
hormone levels.

The outer layer of the endometrium should be a certain thickness of approximately 13 millimeters. For normal development embryo requires maintenance required quantity nutritional elements. It is recommended to strengthen the body before pregnancy.

During implantation of the fertilized egg, the concentration of progesterone should be above normal. It blocks the onset of menstruation, clearing the way for conception.

If these conditions are not met, the attachment will not take place. How to understand that fertilization has occurred, but the fertilized egg has not attached:

monthly bleeding begins;
the embryo is rejected;
a new egg matures.

Pregnancy failure can be caused by:

thick membrane around the egg;
low progesterone levels;
serious abnormalities of the embryo.

If at least one of the above factors is present, the embryo will not attach, which means a spontaneous abortion will occur. If implantation does not occur, menstruation begins after short period time. The onset of menstruation is considered its main sign.

How to help implantation of an embryo in the uterus? Doctors advise taking a Piroxicam tablet two hours before embryo transfer. It is believed that it increases the success of the manipulation.

Implantation with eco

To achieve pregnancy, some families turn to the technique: implantation of a human embryo during IVF. Differences in sensation between conceptions in a natural way and unnatural are invisible. The absence of symptoms of the introduction of the fertilized egg is considered absolutely normal.

But any differences should not be completely denied. An egg that has received fertilization outside the uterus needs time to adapt, which can last a long time; after implantation, it finds itself in a new environment. Quite often, the process of conception is unsuccessful due to the death of the embryo. In these cases, to increase efficiency, implantation of two embryos is necessary.

A significant difference is the time of implementation and the duration of the manipulation. Basically it takes longer with eco. Therefore, if the expectant mother notices any signs, she will feel them longer.

To minimize the risk of embryo failure, to the expectant mother you need to be vigilant and careful:

have a good rest;
do not carry anything heavy;
do not engage in sexual contact;
do not take a hot shower;
avoid hypothermia;
monitor your diet, it should be regular and correct;
spend a lot of time in the fresh air;
do not take long walks;
completely give up bad habits;
do not be in crowded places;
do not come into contact with sick people.

You should be especially careful in the period up to 20 weeks. After this time, the embryo receives additional internal protection, the placenta completes its formation. In obstetrics, it is believed that before this time the fetus was formed, in further period During pregnancy it develops and grows.