According to statistics, about 5% of children are born with congenital malformations.But prenatal diagnosis makes it possible to reduce the risk of having a sick child.It not only allows you to determine the sex of the baby or establish paternity, but also helps to identify congenital malformations of the fetus to determine the risk of possible inheritance "family" of disease, as well as to decide on the further prolongation or termination of pregnancy with a sick child.
prenatal (antenatal) diagnostics - is a complex of medical measures, which aim to detect fetal pathology fetal development Fetal development - week after week .Prenatal diagnosis - is voluntary, but failure, and, respectively, and the possible consequences of its conduct, entirely rests with the prospective parents.
methods of prenatal diagnosis
- analysis pedigree parents;
- genetic analysis for the parents;
invasive (surgical, with the introduction of the uterus):
- chorionic villus sampling;
- screening maternal serum factors;
- ultrasound of the fetus and placenta;
- sorting fetal cells.
parents Pedigree analysis
going pedigree of future mothers and fathers, it appears in the collection of the presence of disease in the family all known relatives,including long-distance.Also specify whether there were infertility, miscarriage or the birth of children with developmental disabilities in this couple.If there is a hereditary nature of the disease, the physician-geneticist defines the path of transmission and the percentage probability of its manifestations in the future remains.
Genetic analysis of parents
Includes the study of chromosomes from each parent of the future.The method is justified by the fact that often in completely healthy people can meet chromosomal rearrangements, which does not manifest itself, but the inheritance of their unborn child can cause developmental abnormalities.
Indications for invasive examination methods of prenatal diagnosis
Invasive prenatal diagnostic techniques are unsafe, can cause the risk of bleeding, miscarriage or injury to the fetus.So they carried out strictly on the evidence, preliminary laboratory testing of pregnant women, a medical specialist in a hospital.
- identified fetal malformations by ultrasound;
- women over the age of 35 years;
- having children with congenital malformations;
- transferred during pregnancy or a history of infections (rubella, toxoplasmosis Toxoplasmosis: pregnant women against cats , herpes Herpes - a virus creeping and others);
- oligohydramnios or polyhydramnios;
- pregnant with abnormalities of serum markers of blood;
- stillbirth history.
Chorionic villus sampling
Held at time of 10-11 weeks.The method consists in the study of chorionic cells (villous placental membranes).It can be carried out in two ways: through the cervix catheter, suction piece chorionic or directly through the abdominal wall of a thin needle inserted into the uterus through which the fence is made of chorionic tissue.The advantages of this method are the fastest results (3-4 day) and the ability to diagnose malformations up to 12 weeks.
This is the same chorionic villus sampling only at a later date (second trimester) of pregnancy.It held only through the anterior abdominal wall.
amniotic fluid sampling is carried out on the subject of their study and fetal cells contained in the amniotic fluid.This method is used at 15-16 weeks of pregnancy, and also performed transabdominal (through the abdominal wall).
This fence cord blood Umbilical cord blood - why keep it? fetal vein of the fetus through the abdominal wall.It carried out after 18 weeks of pregnancy.
All invasive methods carried out under a mandatory ultrasound.
Screening of maternal serum factors
study of maternal serum factors AFP (alpha fetoprotein) and HCG (human chorionic gonadotropin) is carried out between 15 and 20 weeks of pregnancy to all pregnant women.In this case, the venous blood is investigated pregnant.Determining the level of AFP and hCG reveals Down syndrome, some malformations of the brain and spinal cord and many other fetal abnormalities.False positive or false negative results may occur in some cases: multiple pregnancy, especially the woman's body, while delivery of the analysis, the woman's age, and more.This method is effective in 70% of cases.
Ultrasound examination of the fetus and placenta
By order of the Ministry of Health, all pregnant women should undergo screening ultrasound three times for the whole period of pregnancy, at a time of 10-14 weeks, 22-24 weeks, 32-34 weeks.The method is available and quite effective.
ultrasound to determine:
- baby's gender and gestational age;
- fetus and placenta previa;
- amount of amniotic fluid;
- availability and quality of the fetal heart;
- fetal malformations.
sorting fetal cells
Determine erythroblasts and cells of the fetus in the mother's blood in the venous period of 8-20 weeks.
Despite the possible complications during some methods of their high cost and complexity, prenatal diagnosis is necessary for all pregnant women and to determine the risk of having a sick child.Therefore, the future parents in any case should not refuse to prenatal diagnosis, in future, not make life difficult for your child and yourself.