The first trimester of fetal development is a very important period of intrauterine development. At this time, the future baby, who is already actively living in the mother's womb, begins to rapidly develop internal organs and systems. This article tells about the purpose and how the ultrasound of the fetus is performed at 5 weeks of gestation.
What is it for?
An ultrasound scan in the early stages of intrauterine development is used mainly to establish pregnancy. To calculate the period of intrauterine development of a child, gynecologists use the definition of the obstetric period. It is usually 14 days shorter than the gestational age.
4-5 weeks of intrauterine development is a very important period for the embryo. At this time, the fetus begins the most important process - organogenesis... This period is characterized by the differentiation and development of many internal organs and systems of his body.
In most situations, ultrasound is not performed at this early stage of pregnancy. An exception is made when a pregnant woman independently insists on carrying out this method.
This limitation of the performance of ultrasound in the early stages of gestation is very important. The fact is that ultrasound, especially used in focal mode, in the early stages of pregnancy can harm an unborn baby.
Doctors-gynecologists distinguish certain medical indications. If available, they can send the expectant mother to an ultrasound diagnostic room to perform such a study.
An ultrasound scan at such an early date is required, as a rule, in the event that when doctors want to establish the exact location of the ovum... This situation occurs, as a rule, when an ectopic pregnancy is excluded. This pathological condition is usually very clearly visible on ultrasound.
If, despite the clinical examination of the woman and the laboratory tests performed by her, doctors find it difficult to establish pregnancy, then ultrasound also comes to their aid. During such a study, you can also take the first picture of the embryo. As a rule, it is already possible to determine the size of the embryo well on it.
Some pathological conditions that can appear in the very first period of pregnancy can also be detected using ultrasound. Usually, expectant mothers are sent for such a study if they suspect a spontaneous abortion or spontaneous miscarriage.
If, before pregnancy, a woman suffered from any pathologies of the genital organs, then she can also be sent for an ultrasound of the pelvic organs. Such studies help to establish the degree of existing reproductive disorders, as well as to exclude exacerbations of chronic diseases of the genitourinary system in the expectant mother.
Many expectant mothers are interested in whether it is worth undergoing an ultrasound scan at such an early date. Most doctors in this case will say that without a strong need or in the absence of medical indications for ultrasound in the early period of intrauterine development of the fetus, perform such an examination not worth it.
Currently, there are other methods to establish pregnancy.
What will the study show?
Ultrasound performed during this period of development of the future baby, does not yet have high accuracy. This is not at all due to the study on low-quality equipment or the lack of clinical experience of the specialist conducting this test. As a rule, in the early period of embryo development, doctors simply cannot interpret most of the clinical indicators.
During the procedure, an ultrasound diagnostician evaluates only the basic parameters of the intrauterine development of the fetus. It should be noted that there are much fewer such values in the early life of the embryo than during the 3rd trimester of pregnancy.
In each period of intrauterine development of the unborn child, doctors call him various medical terms. At 5 weeks, it is called an embryo. The size of such an embryo, as a rule, does not exceed 3 mm. Such a crumb will not yet be able to "examine" on an ultrasound.
Doctors do not identify the embryo, but the presence of a fetal egg. This formation is a kind of "protective shell" in which the future baby develops. In the future, various fetal membranes will form from the membranes of the gestational egg, which will also protect the fetus from the effects of various adverse factors.
By the end of 5 weeks, two very important anatomical formations of pregnancy begin to form. They are called amnion and yolk sac. The embryo is placed in the amniotic vesicle. This formation is also well visualized using an ultrasound probe.
At its core, the yolk sac is a fundamental organ responsible for the future development and formation of all elements of the cardiovascular system in the unborn baby. From it, as the embryo develops, the heart will form. The baby's heartbeat will appear a little later.
Gradually, small blood vessels begin to form in the microscopic chorionic villi. They will develop and grow in size during pregnancy. This type of blood supply is very important for the embryo developing in the mother's womb.
The chorionic villi of the fetus are in direct contact with the maternal blood vessels. Through them, the baby receives nutrients for its growth and development, as well as oxygen dissolved in the blood.
Some experienced specialists can distinguish many anatomical structures of the embryo as early as 5 weeks. Usually, this also requires not only sufficient experience of an ultrasound diagnostician, but also the use of modern high-precision devices.
Focusing the ultrasound transducer allows the examiner to distinguish quite well the ovum itself. It looks like an elongated formation that attaches to the endometrium - the inner epithelial lining of the uterus.
The inner element of this formation is the amnion. Doctors also call this formation a chamber, which is located inside the amniotic vesicle. It contains a liquid component.
The outer sheath is also fairly well visualized with an ultrasonic transducer. It surrounds the amnion from the outside and is, in fact, the fetal membranes of the embryo.
In this case, a fetal or gestational egg looks like an echo-negative element filled with fluid from the inside. Dorsal amplification of ultrasound is present on the posterior surface of such an anatomical formation. In its shape, the gestational egg can be either oval or round.
On closer inspection, an echo-positive rim is determined around this formation.
Norms of the main investigated parameters
Doctors conducting an early fetal examination use a variety of obstetric concepts and terms. Usually they are used throughout the entire period of gestation.
The size of the gestational egg at 5 weeks of gestation in most cases is ½ cm. To measure this indicator, doctors use special medical criteria. The usual diameter of the gestational egg is determined by only one measurement.
There is another, more precise criterion. It is called the average diameter. To measure it, an ultrasound specialist must take at least three measurements carried out in different planes. This parameter in combination with others can become a criterion for assessing the first weeks of intrauterine embryo development.
There are situations when the size of the ovum obtained during the study is significantly less than ½ cm. In this case, doctors, as a rule, recommend repeating the examination after 6-8 days. Sometimes this indicates "Frozen" or "suspended" pregnancy. To exclude this pathological condition, a second study is carried out.
During the ultrasound examination in early pregnancy, not only the indicators of fetal development are assessed. The condition of the internal genital organs of the expectant mother is also very important for making a forecast for bearing a baby.
Ultrasound helps to identify various neoplasms of the ovaries, cysts, and fibroids. Quite often, these pathologies lead to miscarriage or spontaneous termination of pregnancy at the earliest possible date.
Methodology
Ultrasound in early pregnancy can be done in several ways. The choice of technique depends on many underlying reasons. Usually, the method of conducting such an examination is determined by the gynecologist observing the woman.
You can examine the pelvic organs transabdominal method (through the anterior abdominal wall), as well as transvaginal (through the vagina). In most cases, obstetricians-gynecologists prefer to use transvaginal research method, since it allows you to get more accurate results at this stage of pregnancy.
If the patient has signs of exacerbation of chronic colpitis or vaginitis, accompanied by various vaginal discharge, then doctors may recommend that she conduct a transabdominal study. In this case, no pain or discomfort during the examination will arise.
In order to get a bright picture on the monitor of the device, the doctor conducting the study uses special gel. It is applied directly to the skin. This gel is very hypoallergenic in its composition. It can be used safely even in young children, as well as in pregnant women, without the risk of developing allergies or other unpleasant consequences.
Many women who are referred for an ultrasound scan at the 5th week of pregnancy are interested in whether certain preparation is required before the study. I must say that this is a fairly early date. In this case, no special training is required. However, there are a number of exceptions.
In some situations, the doctor may ask a pregnant woman to come for an ultrasound with a full bladder. This is required in certain cases in order to better view the inner walls of the uterus and the ovum. The filled bladder presses on the uterus, making it more accessible for visualization.
Absolutely all expectant mothers do not need such preparation.
For a couple of days before the study, doctors recommend that women not eat foods that can provoke strong gas formation. Legumes, various types of cabbage, carbonated drinks, fruits and vegetables should still be limited 2 days before the ultrasound scan. This is especially necessary for women who have an increased tendency to gas formation against the background of their concomitant diseases of the gastrointestinal tract.
During the research procedure itself, the woman is on the couch. The starting position is on the back. During the study, the doctor may ask the pregnant woman to turn on her left or right side. This is usually necessary if the expectant mother has any pathological changes or abnormalities in the development of internal organs.
If the study is carried out transvaginally, then the ultrasound probe is inserted into the vagina. During the study, the doctor constantly monitors the general condition of the patient. If during the procedure she has some kind of severe soreness, then the examination may even be stopped. In this case, transabdominal ultrasound is performed.
If a pregnant woman is expected to have twins or identical twins, an ultrasound scan will have a number of features. In this case, one or more fetal eggs are determined. Of particular importance is how conception occurred - physiologically or with the help of IVF.
If pregnancy has occurred as a result of in vitro fertilization, then in this case, the day of embryo transfer into the uterus is also taken into account. This is necessary to establish the obstetric gestational age.
After the performed examination procedure, the patient is given a special medical form with a conclusion. In it, the doctor who performed the ultrasound indicates all the identified deviations, and also fixes the basic dimensions and diameters of the ovum and its anatomical components.
Future moms should definitely remember that the conclusion of an ultrasound examination is not yet a diagnosis. With this form, the pregnant woman goes to the gynecologist. The doctor summarizes all the results obtained and only after that can he establish any diagnoses. In some cases, it may also be necessary to conduct a second study if the doctor doubts the accuracy of the examination.
