Today ultrasonography (US) - one of the most accessible and highly informative methods of research in medical practice, it makes everyone - from infants to the very elderly people.Among the prospective parents there was even a fashion trend-confirming zaklchenie ties made by another expert, learn the future child gender, to make a photo for memory.Unfortunately, many people forget that the US - is still a special medical research, not video filming on memory. What does the US?
As with any study, for ultrasound in obstetrics there are certain indications.
First , for the confirmation of pregnancy, to establish the location of the fetus (in utero or in the abdominal cavity), determining the number of fetuses, determine age and sex of the fetus and the correctness of its development, the recognition of fetal abnormalities and deaths.Image ovum is possible to obtain already at 5-6 weeks of pregnancy.Image embryo - 7-8 weeks.Around the 10th week of pregnancy recorded fetal movements slow.In the period fr
Second , to study the situation, the size and condition of the placenta - the main link through which the exchange of blood between mother and fetus.
Third , this pelvic measurement and assessment of the birth canal (in particular, elimination of obstacles to the generic act, for example, pelvic strain, ovarian cysts and other).
Fourth , hormonal status determination pregnant.Of all these problems, perhaps the most important is the identification of malformations of the cardiovascular and nervous systems of the fetus in the early stages, more precisely, to 20 weeks, when it is possible to terminate a pregnancy.
Underestimate the ultrasound method is not possible.Due to survey virtually eliminated the birth of children with severe disabilities face: cleft hard and soft palate
children with poly- and syndactyly (extra fingers and of fusion)
children with atresia (imperforate), esophagus, intestines.This is not a complete list of pathologies available ultrasonic testing.
Currently in developed countries carry out screening programs ultrasound examinations of pregnant women in the period of 10-15 weeks, 18-24 weeks, 32-34 weeks.
What is ultrasound?
ultrasonic transmitter emits sound waves of high frequency of 3.5 MHz, which are not perceived by the human ear.The waves hit the object, reflected from it and come to a receiving device (receiver), which interprets them as images on the monitor screen.Reflecting on the child, the waves let you see his skeleton and internal organs.Using ultrasound conducted various surveys of pregnant: Ultrasound, dopple-cardiography, echography.The difference is that it explores the doctor (fetus, placenta, fetal heart) and what kind of (diffuse or directional) beam waves for this purpose.For example, in determining the fetal heart, blood flow in the placenta study used a more powerful and directed beam of ultrasonic waves than a total scan, but the beam is not directed to the fetal head, and the study is calculated pair minutes.
What determines the nature of the impact of ultrasound on the patient?It depends on the intensity, exposure time, as well as the sensitivity of living tissue.Ultrasonic energy may have a negative effect if its intensity exceeds 10 W / cm.Emerging with disorders associated primarily with the heating of tissues, which can be added cavitation (formation of gas bubbles in a liquid).It is believed that the use of diagnostic ultrasound energy intensity of 0.05-0.25 W / cm is practically no heating of tissues.But going there with cavitation - is unknown.
However, doctors working within the working day on the UT-aplaratah, note the occurrence of tingling in the fingers.Therefore, on the US Now there unique point of view: most physicians believe that it is a harmless procedure, and it can be carried out many times without any damage to the health of mother and baby.
But at the same time there are increasing alternative views: for example, the US National Institutes of Health has not approved the mandatory ultrasound of pregnant women.In Japan, pregnant ultrasound is performed only after serious justification for this study.Why do countries with a high level of care, where missing, and ultrasound equipment, and specialists who know the procedure still restrict the use of this method?Western experts substantiate the existence of such tactics unrecognized risk.
Although argues that people do not perceive the sound frequency used, has not yet been explained by the fact that children in the womb, it is extremely rapidly respond to the survey, answering it heavy traffic.Let the purely theoretical risk.But if the benefits of the research, not even a theoretical risk can not be justified.When this is used as data arguments that adversely affects the ultrasound chromosomes, in particular, can lead to mutations of the fetus, fetal growth delay in animal experiments, changes at the microscopic level found in studies on tissue samples.
In addition, one of the facts that alarmed the public, was a strange pattern.It turned out that mothers who have passed this procedure several times, the children were born, weighing slightly less than babies mothers, makes ultrasound only once - at the 18th week.As a result, the scientists decided to watch the nearly three thousand children for eight years.It was found that babies exposed to ultrasound repeatedly caught up by weight peers to have their first birthday.Furthermore, no abnormalities in the development of such babies were detected.Study leader John Newnham stressed that today's machines reduce procedure time and provide better image quality.And mothers who still doubt the safety of ultrasound, professor promises to continue monitoring the children and a few years later to publish the new data.
extent necessary ultrasound?
use of ultrasound during pregnancy should be particularly prudent.Neither curiosity parents nor convenience doctor can not be an argument.Undoubtedly, the US has greatly facilitated the work of Obstetricians and reduced the number of unpleasant "surprises".However, as a result of excessive use of this method, obstetricians have become too much to rely on it.The heartbeat of the fetus not necessarily listen to using ultrasound, for this is fetoscope, harmless to the child.To determine presentation and position of the fetus in the uterus, too, do not need to ultrasound, it needs the hands of competent obstetrician.
Weighty bases for US considered:
• predisposition to hereditary diseases
• born in a family of children with developmental abnormalities
• impact on pregnant radiation or chemical agents
• transfer of serious diseases and viral infectionsresulting in malformations, chronic maternal diseases such as diabetes, phenylketonuria and other
• suspicion of placenta previa or premature detachment of the placenta
• such trouble pregnancy as molar pregnancy, ectopic pregnancy, developing pregnancy, delayfetal development.
In these cases, the frequency and duration of the study dictates the need to preserve the health of the mother and child, so it is difficult to find an alternative method of research that is comparable with ultrasound.