In this article we will talk about what constitutes and when the placenta is formed during pregnancy. We will answer many questions asked by women in an interesting position. We will try to pay more attention to the structure of the organ, its development and pathologies.
It is important to remember to all women that even at the very beginning of pregnancy, the formation of the system begins in the body, which is commonly called the "mother-placenta-fetus". How many weeks does the placenta form during pregnancy? What functions does it perform? You can learn all this from the article brought to your attention. This organ is an integral element, because the placenta, which has a complex structure, plays a vital role in the development and formation of the unborn child.
What is the placenta?
Many women ask questions: at what week of pregnancy does the placenta begin to form, what pathologies and structural disorders are possible? To answer them, you need to find out what it really is.
This amazing organ has a very interesting feature, because the placenta belongs to two organisms at once (both mother and baby). It is from its proper development and location that the vitality of the crumbs depends. The placenta also has another name - a child's place. This body is temporary, because right after the birth of a child, it is rejected by the female body and ceases its activity.
So, when is the placenta formed during pregnancy and what does it consist of? If we turn to the morphology of the organ, we can find the following: the placenta is an accumulation of some cells: chorion, outgrowths of the germinal membrane.
They grow into the uterus and are constantly growing. During development, chorions become like a child's place. When will the placenta form during pregnancy completely? The process of growth and development of the organ stops at the twelfth to sixteenth week of pregnancy. Where does such a strange name come from? The name has Latin roots, translated into Russian, the word placenta means “disk” or “flat cake”. This form should be a matured placenta.
As mentioned earlier, a child's place is an organ that belongs to both the mother and the baby. Two organisms communicate through the placenta through the umbilical cord. The latter, in turn, consists of arteries and veins. With the help of an artery, the baby’s body is delivered oxygenated blood and nutrients. Vein is used to discharge processed substances. Normally, the umbilical cord should be between fifty and fifty-five centimeters long, although there are cases when it is much shorter or several times longer.
Structure
What is the placenta formed from? It includes:
- decidual tissue ;
- embryoblast;
- trophoblast.
The main component of this organ is the villous tree. As mentioned earlier, the placenta is necessary for the life support of the child. It is very important that there is no mixing of the blood of the mother and the fetus, since there is a placental barrier. This protection is very important, as it prevents Rhesus conflict.
With a normal pregnancy, the weight and size of the placenta increases in proportion to the development of the fetus. But until about the fourth month, the placenta develops a little faster than the baby. If the child died for any reason, the placenta ceases its activity and also dies. In this case, an increase in dystrophic changes can be detected. With the normal development of pregnancy, the placenta reaches full maturity only by the fortieth week, this suggests that villi and blood vessels stop developing and forming in it.
As mentioned earlier, a mature placenta has the shape of a disc, the thickness of which is up to three and a half centimeters, and the diameter is about twenty centimeters. The weight of the organ is about six hundred grams. Both sides of the placenta have some differences.
- The maternal side is facing the uterus. It is rough and formed from the basal component of the decidural membrane
- The fruit surface is facing the baby. It is covered with an amniotic layer. Under it, you can clearly distinguish blood vessels.
Now briefly discuss the question of when the placenta is formed during pregnancy by twins. It is important to note that the type of it (or theirs) will directly depend on the implantation of eggs.
Dizygotic twins are implanted separately. Based on the fact that they are found in the uterine cavity almost simultaneously, they can be implanted both in opposite angles and nearby. If implantation occurred nearby, the placenta may seem to be a single whole, but in fact it is not, each of them has its own vascular network and membranes. When implanted at a considerable distance, it is possible to easily find two placentas using ultrasound.
The fetuses of the dichoric twins are separated by a septum. It is important to note that this shell has virtually no vessels. Therefore, they receive nutrition from amniotic fluid.
With monozygous twins, the placenta is one, but the babies are separated by a thin transparent film. In most cases, the crumbs have blood vessels that combine blood circulation in the entire placenta, which is not very good. In this case, there is a danger of transfusion syndrome.
There is also monoamniotic monochorial twins, when the partition between the fruits is completely absent.
Development
You have already been able to find out from the article at what week of pregnancy the placenta is formed, how it is arranged, now we will trace its development. It begins to arise at the time of fertilization. Active growth begins only from the second week of pregnancy, by the thirteenth its structure has already been formed, and the peak of activity is eighteen weeks of gestation. But it is important to note that her growth and development are completed only after the birth of the baby.
So, when does the placenta begin to form during pregnancy and how does it change in the process of its development? The structure of this body varies depending on the needs of the crumbs. The peak of her maturity occurs at about thirty-fifth week. The structure of the placenta is changed in order to satisfy all the needs of the baby. And the process of growth and change in the placenta is usually called maturation, which is monitored by ultrasound throughout the pregnancy. It is important to note that there is a generally accepted classification of maturity, judging by which:
- 0 - up to thirty weeks;
- 1 - until the thirty-fourth week;
- 2 - up to thirty-seven weeks;
- 3 - up to thirty-nine weeks;
- 4 - until the time of birth.
This indicator helps to prevent and notice pathology in time. A placenta that does not match the gestational age indicates abnormalities. For example, if the placenta has matured ahead of schedule, then this is a warning about impaired placental blood flow. This can result from late toxicosis or anemia. Despite this, there are exceptions - the genetic predisposition of the expectant mother. If we consider the opposite situation - the placenta develops more slowly - then this deviation is not considered if the child does not suffer from this phenomenon.
We have already considered the optimal sizes, but did not mention one fact: the placenta immediately before the birth of a baby is reduced in size.
How else can you control the condition of the placenta? Another method for determining the functional well-being of an organ is the detection of the hormone lactogen, which is secreted by the placenta. It is he who can inform about her normal condition. If there are no violations of placental function, then the indicator should be more than four μg / ml.
Another method is daily monitoring of the excretion of estrogen or estriol. If the concentration in urine and blood plasma is low, then this indicates:
- severe liver damage;
- taking antibiotics;
- renal failure.
Location
We figured out when the placenta is formed, what are the stages of its maturation, now briefly about the correct location. With a normal pregnancy, the placenta is formed in the uterine cavity on the back wall with a smooth transition to the sides. How can this be explained? The fact is that it is the back wall that is less susceptible to changes during pregnancy and is protected from injuries. However, there are women in whom the placenta is located on the front wall or even on the bottom of the uterus.
Functions Performed
When a placenta is formed during pregnancy, it is assumed that it will perform some important functions. The main one is maintaining the normal course of pregnancy, ensuring the growth of the child. Functions:
- protective;
- endocrine;
- respiratory
- nutritious;
- immune
You have learned how long the placenta is formed during pregnancy, what functions it performs, now briefly explain each of them. The first, protective, means that it protects the baby from the environment. The second is the production of a number of hormones (estrogen, lactogen, progesterone, and so on), the transportation of hormones from mother to baby. Respiratory - gas exchange. Nutrient - delivery of nutrients. Immune - suppression of the conflict of the body of the mother and child.
Placenta maturation
To answer the question of which week of pregnancy the placenta is fully formed, it must be recalled that there are five stages of maturation of this organ. As mentioned earlier, by the degree of maturity it is possible to determine the presence of deviations.
Once again, we recall that in the normal course of pregnancy in a woman at thirty-fifth week, you can find the following parameters of this body:
- thickness up to four centimeters, but not less than three and a half;
- weight - about half a kilogram;
- diameter - up to twenty-five centimeters, but not less than eighteen.
Afterbirth
Many women, especially those who are pregnant with their first child, believe that the entire birth process consists of two stages:
- contractions;
- giving birth to a baby.
However, this is a mistake. Immediately after the birth of the crumbs, another stage follows - the separation of the afterbirth. Pregnant first-born women are hard to imagine what it is. However, you should not worry, the medical staff will certainly do everything to ensure that everything is in order with your health and well-being of the crumbs. The aftermath is the placenta, umbilical cord and amniotic membranes that formed in the first trimester of pregnancy and protected the baby throughout the pregnancy.
Department of the placenta
The last has such a name because it comes out last. After the birth of a child, the need for this organ disappears, and for the quickest restoration of the uterus, it is necessary to completely clear its cavity. All tissues that a woman’s body does not need leave him alone, but if suddenly the placenta does not separate itself, then the medical staff will do it forcibly.
Pathology
We examined in detail the structure and norms of the placenta during pregnancy. Pathologies of the development of this body (although not all) can harm the baby. The main thing is to notice the problem in time and eliminate the cause of its occurrence.
Here are the main violations:
- lag in ripening and vice versa;
- detachment;
- blood clots;
- inflammation;
- thickening;
- low location of the placenta;
- tumor;
- placental infarction and so on.
The reason may be the presence of a pregnant woman:
- toxicosis;
- diabetes mellitus;
- atherosclerosis;
- infections
- rhesus conflict;
- late pregnancy (for 35 years);
- stress
- bad habits;
- overweight or lack thereof.
Fetoplacental insufficiency
We have already answered the question of when the placenta is fully formed during pregnancy, but did not say about deviations in its development. One of the most common problems is fetoplacental insufficiency. The disease is the reason for the lag in the development of the child, as there is a lack of nutrients.
It is important to note that it is impossible to completely cure the disease, but under the supervision of a doctor, therapy with some drugs that improve blood flow is possible.
Structural disturbances
In the structure of the placenta, there may be the following violations:
- the presence of only two shares;
- the presence of an additional share;
- fenestrated placenta.
Such violations can not harm the child, but slightly complicate the process of discharge of the placenta. The doctor should be warned about this pathology, since measures will be taken to forcibly discharge the afterbirth. This will help prevent bleeding or infection.
Symptoms of pathologies
A woman should listen to her body. Symptoms of pathology can serve:
- bloody issues;
- stomach ache;
- hypertension;
- swelling of the body;
- cramps
- dizziness;
- headaches.
If these symptoms are found in a woman, she should immediately consult her doctor.