For the full intrauterine development of the fetus, a placenta is required. It can be located in the uterus in different ways. This article will help you understand what the location of the placenta on the back of the uterus means, and what it affects.
What does it mean?
Placental tissue is laid early enough during pregnancy. Already in the second trimester of pregnancy, it begins to function fully. The placenta contains various blood vessels, through which the fetus receives the nutrients necessary for its growth and development, as well as dissolved oxygen.
How the placenta is attached to the uterine wall determines how the intrauterine development of the baby will proceed, as well as the course of pregnancy as a whole.
The location of the placenta and its initial localization are determined practically from the first days after conception. It all depends on where the fertilized egg will be located. In most cases, it is implanted (tightly attached) into the inner wall of the uterus in the region of its bottom along the back wall. This feature of implantation is due to nature. It has been established that this zone has the best blood flow.
The presence of blood vessels in this anatomical zone of the uterus also contributes to the physiological growth of the chorion. In such a situation, it grows and develops quite quickly and fully. Note that in most clinical cases, the placenta along the posterior wall of the uterus is located quite high - almost in the area of the uterine fundus, that is, in its upper part. The distance to the internal uterine pharynx is large enough.
In certain situations, the fertilized egg changes its attachment site and is implanted in the lower uterus. This situation can be dangerous and usually leads to the development of low placement of the placenta or presentation.
Normally, there is a certain distance between the placental tissue and the internal pharynx. It is different at each stage of pregnancy. So, normally in the 2nd trimester of pregnancy it is 5 cm, and by the third it changes to 7 cm.
If the placental tissue is almost completely adjacent to the internal uterine pharynx and even directly finds itself on it, then such a pathology is called presentation.
Doctors identify several clinical options for placenta previa: it can be central, lateral or marginal. It all depends on the zone in which the placental tissue is displaced to the area of the internal uterine pharynx.
So, the central presentation is characterized by a displacement of the central part of the placenta to the area of the internal os. With lateral presentation, the placenta is in contact with the pharynx from the area of the lateral walls, and with the marginal - only by separate edges.
Also, placenta previa can be complete and partial. With full presentation, almost all placental tissue is located in the area of the internal uterine os. If the placenta is in contact only in separate areas (parts), then such a presentation is called partial or incomplete.
The severity of adverse symptoms and possible complications significantly depends on how the placental tissue is located relative to the internal uterine os. This also determines the nature of the course of pregnancy. Experts note that the attachment of the placenta along the posterior wall of the uterus occurs in most clinical cases.
Features of the course of pregnancy
With the normal location of the placental tissue along the posterior wall of the uterus at a considerable distance from the uterine pharynx, the course of pregnancy usually proceeds quite physiologically. Good blood flow to the fundus and the back of the uterus ensures optimal fetal growth. In such a situation, the risk of developing any complications and adverse consequences is quite low.
If, for some reason, the placental tissue shifts down the posterior wall below and reaches the internal pharynx, then the course of pregnancy is already complicated by the development of presentation. In such a situation, the risk of developing unwanted complications increases significantly.
It is important to note that placenta previa on the back of the uterus is more favorable. The prognosis of the course of pregnancy in this case is quite good.
So, the risk of developing mechanical damage to the placental tissue, which is located on the back wall, is much lower. This is due to certain anatomical features of the structure of the female body. In front, the placenta is protected by the anterior abdominal wall and pelvic bones, and behind by the skeleton of the spine. Such reliable protection minimizes possible trauma to the delicate placental tissue.
Is placental migration possible?
The change in the initial localization of the placental tissue is called migration by specialists. It usually lasts for several weeks and is not accompanied by the development of adverse symptoms. However, during pregnancy with placenta previa along the posterior wall of the uterus, the possibility of migration of placental tissue, unfortunately, is extremely low.
Many obstetricians-gynecologists believe that in this position, the placental tissue practically does not change its original localization. Only in extremely rare cases is its migration possible.
In this case, it is very important for a pregnant woman to monitor her well-being. The appearance of bloody discharge during 2-3 trimesters of pregnancy, especially if it develops spontaneously, should be a good reason for an urgent visit to a specialist. In this case, there is a high risk of bleeding or even placental abruption.
How to determine?
The location of the placenta can be established in various ways. So, the localization of the location of the placental tissue is determined by conducting a conventional routine vaginal examination. The doctor, conducting such an examination, must necessarily assess where the placenta is located.
If the placental tissue is too low and its presentation develops, then too frequent vaginal examinations should not be performed. In this case, the delicate tissue of the placenta can be easily damaged. It is also very important that the vaginal examinations are performed by a qualified professional. Accuracy in carrying out such gynecological examinations is very important.
An ultrasound examination is a more accurate way to determine the location of the placenta. With the help of modern equipment, it is quite easy and accurate to determine where the placental tissue is located. An experienced and qualified specialist can also quite easily determine the distance from the placenta to the uterine pharynx.
If during pregnancy the diagnosis of placenta previa is established, then in such a situation the expectant mother is assigned several more repeated ultrasound examinations. This allows doctors to monitor the dynamics of the course of pregnancy, as well as timely establish the onset of the formation of possible complications. Such an ultrasound examination in dynamics makes it possible to assess the migration of placental tissue, if it does occur.
If there is placenta previa, then preference is given to transabdominal ultrasound techniques. During them, the ultrasonic sensor is located on the surface of the anterior abdominal wall.
Performing a transvaginal ultrasound scan while the probe is inserted into the vagina can lead to bleeding. As a rule, this examination is not performed when presenting.
How is labor done?
When choosing the tactics of obstetrics, the localization of the placenta before childbirth plays a huge role. If it is quite high, and the pregnancy is physiological, then in such a situation, doctors can also allow natural childbirth. In this case, the child is born without the use of a cesarean section.
If the placenta, located on the back wall of the uterus, is too low or even has its presentation, then in such a situation the option of carrying out a surgical method of obstetric aid is already being considered. In this case, as a rule, a cesarean section is required.
Note that such a delivery surgery is performed in order, first of all, to preserve the health of the mother and her baby.
Also, a cesarean section is also performed for those women who have a complicated obstetric and gynecological history. The presence of severe concomitant chronic diseases is an important reason for the appointment of a cesarean section. In this situation, natural spontaneous childbirth may be too dangerous.
An important goal in the management of pregnancy, complicated by the development of placenta previa along the posterior wall of the uterus, is its possible long-term preservation. In such a situation, a baby born into the world is more functionally adapted for life in a new habitat.
The choice of obstetric tactics is individual. This is influenced by a huge variety of different factors. The tactics of managing a pregnancy complicated by placenta previa along the posterior wall of the uterus can change several times during the entire period of gestation.
What should be considered?
Pregnancy in which the placenta is located at the back of the uterus usually goes well. However, this does not at all exclude planned visits to the doctor and the passage of screening examinations recommended by him.
During the gestation period, numerous changes can occur in the female body. At any time, the course of even a physiological pregnancy can be complicated by the development of complications. In order for them to be identified on time, the expectant mother should regularly visit her obstetrician-gynecologist.
If, during the examinations, the doctor determines the placenta previa, then, first of all, you should be very careful about this. The behavior of the expectant mother and her attitude towards her own health are a very important component for carrying out such a pregnancy.
The appearance of bloody discharge from the genital tract, the occurrence of a sudden and severe pain syndrome in the abdomen should be important reasons for contacting a specialist for advice.
With placenta previa on the back of the uterus, doctors make up a number of recommendations. They are mainly aimed at reducing the development of dangerous complications, such as bleeding or placental abruption. An expectant mother who has placenta previa should not lift heavy objects and actively engage in physical activity. Also, to improve overall well-being, she should eat well and get enough sleep, and, if possible, limit any stress and nervous shock as much as possible.
You will learn more about the importance of the location of the placenta in the following video.
