How is the KTP calculated?
As a rule, this parameter is set at the same time, when a planned ultrasound of the fetus is carried out. To calculate the CTE, the uterine cavity is scanned in different planes to examine the fetus from all sides, and select the largest index of the length of its tiny body.
For what and when is the KTP measured?
Measurements of the coccygeal-parietal size of the baby are carried out at certain times. The values of the CTE of the fetus are compared with the table, which indicates the norm for certain weeks of pregnancy. This allows you to respond in time to changes in prenatal development and diagnose the disorder at an early stage.
As you know, the period of the first planned ultrasound is usually 10-12 weeks. In addition, in addition to assessing the state of the cardiovascular system, the brain, determining the sex of the baby, the KTR measurement is also performed.
This indicator, as a rule, is informative only up to 14 weeks. Therefore, the earlier the KTR measurement is carried out, the better. The last implementation of this procedure can be carried out no later than 15 weeks. The thing is that by this time other indicators of intrauterine development have come to the forefront. That is why in the KTR table the values of the norm are written only 13 weeks inclusive.
How are the results evaluated?
As already mentioned above, the norm of the CTE of the fetus varies by weeks. Therefore, the doctor should evaluate the results.
So, at the gestational age of 6 weeks, the CTE is normally 7-9 mm. However, at the next week, week 7, it is 10-15 mm. By the 10th week, the embryo reaches a size of 31-39 mm, and at 12-13 it reaches 60-80 mm.
The KTR table clearly shows that this parameter is increased by 1 mm every day until 12 weeks of pregnancy. But from the 13th week of intrauterine development, the baby begins to grow rapidly, adding 2-2.5 mm per day.
Why is KTR measured?
During the entire 1 trimester of pregnancy, the baby is measured in the womb from the coccyx to the crown. This is explained by the fact that it is rather difficult to measure the fruit in another way. the dimensions of its legs are very small and the position of the embryo prevents it from doing so.
As the baby straightens, it is measured from the top to the heel. At the same time, it's difficult to do it right away. Therefore, make the addition of the length of individual parts of the trunk, which is to establish the growth of the baby. In this case, the fetus is first measured from the crown to the thigh, then the length of the thigh itself, and then the shank is measured. However, most often, the doctor does not add these values, comparing their values with the rates of the individual.
Thus, every future mother should know what the CTE of the fetus means and what it is calculated for. However, you should not independently compare the results of measurements with tabulated values, and draw any conclusions. All this is the duty of doctors who analyze the findings, taking into account not only the numerical values, but also the pregnancy, the term, the multiple pregnancy or not, the growth of mom and dad, etc. Only considering all the characteristics mentioned above, one can draw a conclusion about the fetal condition and analyze its fetal development, having established deviations from the existing norm, if any, take place.
