Norm screening ultrasound 1 trimester
With the onset of pregnancy the woman begins to bother a lot of questions. Every expectant mother wants her baby the normal formation and development. In the early stages there may be a risk of the development of certain diseases of the embryo. To study the state of the baby doctors prescribe screening 1 trimester. Standards in ultrasound (photo surveys normally attached) woman can ask the specialist who is watching her.
What is prenatal screening?
Prenatal screening involves the study of pregnant women, allowing to identify various defects of the child at the stage of fetal development. This method includes two kinds of tests: biochemical blood test and an ultrasound test.
The optimal time for screening is the period between ten weeks and six days to thirteen weeks and six days. There is a normal screening ultrasound 1 trimester, which compares the results of examination of the pregnant woman. The main task of the ultrasound at this time is the definition of serious malformations of the embryo and identification of markers of chromosomal abnormalities.
The main anomaly is:
- size TVP — thickness space the neck area
- underdevelopment or absence of the nasal bones.
Ultrasound during pregnancy allows to reveal signs of diseases such as down syndrome and some abnormalities of the fetus. Norm screening (ultrasound) 1 trimester should be analyzed before 14 weeks. After this period many of the indicators are already uninformative.
Screening 1 trimester: the norm for ultrasound (table)
To the doctor was easier to determine the condition of a pregnant woman, there are certain tables of indicators of development of organs of the baby. The Protocol the ultrasound examination is issued is structured to understand the dynamics of the formation and growth of the embryo. The article presents screening standards 1 trimester.
Transcript of ultrasound (table given below) will help to obtain information about whether all is in order with the fruit.
The name of the authority (criterion)
to twelve weeks
The determination of the viability of the embryo
To assess the viability of the embryo is very important to look at the heartbeat in the early stages. The little man's heart starts beating in the fifth week of stay in the womb of a mother, and to identify it using the 1 trimester screening (norm for US), you can have seven weeks of life of the fetus. If the heartbeat is not detected, it is possible to speak about the likelihood of fetal death (missed abortion).
To assess the viability of the embryo is also taken into account the heart rate, which normally for a period of six weeks is around 90 to a hundred and ten beats per minute. These important screening 1 trimester, norms ultrasound research of the blood flow and the body length must match the reference data in pregnancy.
The more modern equipment is used for examination, the better you can see all the agencies and get the most accurate results. If there is a high chance of having birth defects or genetic anomalies, the mother sent for further examination.
In some regions at statement on the account in female consultations is mandatory for all pregnant women screening 1 trimester. Standards for ultrasound may not coincide with the obtained results, so the doctors immediately take the necessary measures to preserve the life or health of the child or mother. But most often such direct examination of pregnant women, at risk: women from thirty-five years, those who have genetic diseases in the family and those born before the children, had a miscarriage in previous pregnancies, stillborn offspring or missed miscarriage. Attention is also given to expectant mothers who have had early in pregnancy viral illness taking dangerous drugs or under the influence of radiation.
If a woman has spotting in the first trimester, ultrasound allows us to reveal the degree of viability of a child, or death.
Further investigation to determine the exact date the state of pregnancy shown women with irregular menstrual cycles or who do not know even approximately the date of conception of the child. To do this, in most cases used screening 1 trimester. Standards for ultrasound, the decryption key indicators and the date of conception not warrant special medical knowledge. The woman herself can see the expected delivery date, gestational age and number of embryos. Basically, the number of weeks determined by ultrasound, corresponds to the period calculated from the first day of the female cycle.
While doing research, the doctor makes measurements of the size of the embryo. Information specialist compares screening standards 1 trimester. Transcript of ultrasound occurs according to the following parameters:
- measure the distance between the sacrum and the top of the head of the embryo (7-13 weeks), giving the opportunity to determine the real duration of pregnancy according to special tables
- the measurement of the length of the parietal bone of the head of the unborn child (after 13 weeks), this is an important indicator in the second half of pregnancy
- determination of the size of the longest — thigh body of the embryo, its indicators reflect the child's growth in length (14 weeks), in the early stages it should be approximately 1.5 cm, and the completion of childbearing to increase to 7.8 cm
- measurement of abdominal circumference in a child – indicates the size of the embryo and its alleged weight
- the definition of the circumference of the head maturing fruit, which is also used for the prediction of natural birth. This measurement is carried out in the last stages of pregnancy, in which the doctor looks at the size of the pelvis of the expectant mother and the child's head. If the head circumference exceeds the parameters of the pelvis, is a direct indication for caesarean section.
Definition of malformation
Using ultrasound in the first weeks of pregnancy reveal different issues in child development and the opportunity to cure it before birth. For this there should be an additional consultation of the doctor-genetics, which compares the examination performance and screening standards 1 trimester.
Transcript of ultrasound may indicate the presence of any malformations of the child, but the final conclusion only after carrying out biochemical studies.
Screening 1 trimester standards for sonography: nasal bone
In embryos with chromosomal abnormalities, ossification is later than in healthy controls. This can be seen even at 11 weeks when screening 1 trimester. Standards for ultrasound, the transcript of which will show whether abnormalities of the nasal bones, help the expert to determine its value since 12 weeks.
If the length of this bone does not date the pregnancy, but all other indicators are in order, for concern reasons. This is most likely the individual characteristics of the embryo.
The value of fetal crown-rump length
An important indicator of the development of the little man at this point in the pregnancy is the size of the coccyx to the crown. If a woman had irregular menstruation, according to this indicator, determine the duration of pregnancy. Norm screening ultrasound 1 trimester this index ranges from 3.3 to 7.3 cm for the period of ten to twelve weeks inclusive.
The thickness of the space in the neck area (NT)
Otherwise, this indicator is also called thick neck folds. It is seen that if NT embryo thicker than 3 mm, there is a risk of down's syndrome in a child. The values used by the doctor shows the 1 trimester screening. Standards for ultrasound (nuchal translucency thickness) are considered very important for further observation of the pregnant woman.
Definition of placenta
The children's place (placenta) necessary for the fetal blood supply to the little man. It is necessary to provide food. Ultrasound gives the ability to determine anomalies of development and position of the placenta. If it is located too low in relation to the bottom of the uterus this is called placenta previa that could lead to the overlapping of the exit for the baby during childbirth.
Good to show location of child seats can ultrasound screening 1 trimester. Rules of this study to reject low placenta previa. But even if it is located close to the bottom of the uterus, doctors do not rush to sound the alarm, as with pregnancy it can go up. But if the position of the placenta is not changed in the later stages, you may experience the following problems:
- the placenta can cover the cervix and prevent a natural childbirth
- as in the second trimester the lower part of the uterus stretches, the placenta can from it to flake and cause severe bleeding (placental abruption).
The study of the yolk SAC
At 15-16 days gestation from the day of conception the process of forming the yolk SAC. The "temporary on" baby explore, making ultrasound (screening 1 trimester). The timing and standards for ultrasonic examination must show its presence and size. If it has an irregular shape, enlarged or reduced, it is possible that the fruit froze.
The yolk SAC is an appendage located on the ventral side of the embryo. It contains a supply of yolk, is necessary for normal development of the baby. So check what the normal screening ultrasound 1 trimester in comparison with the parameters of the study, it is very important to monitor the pregnancy. Because at first (until the organs of the child do not function independently) this Appendix performs the function of the liver, spleen, and is also used as a supplier of primary germ cells, are actively involved in shaping the immune and metabolic processes.
The role of biochemical analysis of blood
Exploring the status of embryos, the doctor looks at not only the results of ultrasound (screening 1 trimester). The norm is the same as in the blood. This analysis in addition to the ultrasound examination is performed to determine at what level are specific proteins (placental). The first screening is done in the form of a double test to determine the levels of 2 protein forms:
If the levels of these proteins changed, it indicates the possible presence of different chromosomal and extrachromosomal disorders. But identifying high-risk does not mean that the embryo is definitely something wrong. These results screening in 1 trimester, transcript, normal ultrasound suggests that the need to more carefully observe the pregnancy. Often repeated study no longer shows the risk of genetic diseases.