Down syndrome signs in pregnancy, diagnosis and prevention
In the mid-18th century English doctor named John Langdon Down described the symptoms at that time was called “Mongolism” because of the characteristic shape of the eyes. John Langdon made the first step for the study of “Mongolism”. Later on the name of the doctor, first described the disease as a form of mental disorder, and began to call people with such disease.
Down syndrome is one of the most common diseases. The disease is associated with changes in chromosomes. These children are similar problems in health, the General features and body shape. With a large investment in the children of funds, time and attention in the future, they lead full lives, have their family, though often do not have the ability to procreate. Unfortunately, not every parent can devote themselves fully to the child. Many moms give up and go for an abortion, after learning about the disease during pregnancy.
Causes of disease still not known. Down syndrome children are born in both poor and wealthy families. The birth of a child may both healthy and sick parents. The average life expectancy of a person with down syndrome is 49 years.
Mechanisms of development
A man develops in the incorporated program. The role of the media played by the chromosome. In a healthy person 46 chromosomes. They are divided in pairs, 23 pairs is obtained. Each pair has its own number assigned to scientists. Chromosome number 21 is represented by three copies, because this disease is the scientific name of “trisomy”. This extra chromosome creates changes in the child’s development. If in the first year of life they are not visible, that with each subsequent year the differences between normal children and children with pathology of down syndrome occur every month. Therefore, in the first year of a child’s life with trisomy you must attach to it the maximum attention of both healthcare professionals and parents.
The types of the disease
Down syndrome is found in several variants:
- Trisomy – the most common type. In 94% of the children found this variant of the disease. Pathology formed during the formation of gametes (sex cells of the parents). In the 21st chromosome, there are three homologous chromosomes instead of two.
- A Robertsonian translocation. Occurs when the displacement of the long arm 21 of a pair to the other chromosome during the development of germ cells in the embryo. Found only 2 – 3% of children with the disease. It is expressed poorly, children with this form develop almost on a par with normal children. The possible transmission of the disease in generations.
- Mosaic form of triple chromosome found only in 2% of children with pathology. Formed in the early stages of development of the embryo (the sex cells of the parents normal). Disorders affect only part of the cells of the body, so changes will be less pronounced.
In a mosaic form, the child has a few differences from healthy children. This diagnosis is difficult to confirm. Male with a mosaic form are able to reproduce offspring. In other cases, infertility is normally recorded.
Causes and risk factors
The birth of a child with down syndrome without a special examination during pregnancy is an unexpected event. But some signs can predict the possible development of pathology. Among them are the following reasons:
- Closely related to marriage
- Late delivery mom. After 35 years increases the risk of having an affected child is 1: 214. After 45 years the probability is 1:19. For comparison, the risk of having a child with down syndrome under the age of 35 years does not exceed 1:1000.
- Father’s age (over 42 years).
Frequency the birth of a child with down syndrome does not depend on economic status. Sick children with the same frequency are born in the third world countries and in the prosperous developed countries. According to statistics, the world has witnessed one case of birth of a sick child in 700 births. Thanks to modern prenatal diagnosis this figure fell to 1: 1000.
Down syndrome cannot be infected. Its development is not affected by the area of residence, pregnancy, modified products, or increased radiation. The disease is not inherited. This syndrome is considered to be a random genetic mutation. If you refused the abortion, and the baby is born, the best thing you can do is to love him the way he is and help him adapt to real life.
Down syndrome can be identified by external features in 90% of cases. Children with trisomy are similar, and have little or no similarities with their parents. The characteristic facial features of Downey and other anomalies inherent in the extra chromosome:
- low weight — less than 3 kg and height up to 50 cm (at birth);
- flat face;
- brachycephalic (short skull);
- skin fold on the neck;
- the eyes narrow and slanted shapes similar to Mongolian;
- flat nose bridge;
- spot Brushfield on the edge of the iris (more often in blue-eyed children), spots size reaches to 1.5 mm, they look like beads;
- neck low, wide;
- language large, will not fit in the mouth;
- narrow, arcuate sky;
- not closing the mouth;
- asymmetrical shell ear, ear passages narrowed;
- muscle weakness;
- hypermobility of the joints;
- the shortening of the fingers;
- fold under the big toe;
- transverse skin crease on the palms;
- anomalies of the dentition;
- the shortening of the nose;
- congenital heart disease;
- deformity of the chest;
- atresia of the duodenum;
- intellectual impairment;
- speech disorders;
- mental deviations.
The symptoms described occur in healthy children. For accurate diagnosis requires genetic analysis.
During pregnancy with the help of certain tests and ultrasound has the ability to ensure the health of the developing child.
Ultrasound to determine down syndrome is carried out during the period 12 – 14 weeks. Earlier screening is impractical because of the high risk of diagnostic errors. Ultrasound recommended for all women in the state. The sooner you get diagnosed, the less damage will be inflicted by the abortion is the woman’s body.
During the ultrasound examination, the following signs are viewed:
- the absence of the nasal bone (not visualized);
- NT – nuchal translucency thickness more than 3 mm.
These parameters are calculated at the first ULTRASOUND screening. At this point, you can terminate the pregnancy (before 22 weeks). If a woman refuses to have the abortion, it is directed to the second ULTRASONIC screening for the period 18 – 21 week. During this period, assessed the status of the fetus and the identification of possible defects:
- shortening of tubular bones;
- reduction of the iliac bones;
- a decrease in frontal lobe;
- anomalies in the structure of the cerebellum
- the size from the coccyx to the top of the fruit less than normal;
- intestinal pathology;
- heart disease;
- one umbilical artery.
Competent diagnosis based on ultrasound can supply highly professional doctor. The more identified these symptoms, the higher the risk of complications.
Prenatal screening studies to detect genetic abnormalities in the fetus of pregnant women, including down syndrome.
The surveys are invasive and non-invasive.
Safer for baby are non-invasive survey. They include biochemical screening:
- double test – 10 to 14 weeks (HCG and PAPP-A);
- triple test – 16 – 18 weeks (HCG, AFP, estriol).
Transcript analyses involved the doctor. The results of the screenings, you can make assumptions about the status of the fetus. In combination with an ultrasound system (PRISCA) method accurately calculates the risk of having a child with down syndrome and determines the further tactics of management of women.
If any abnormalities pregnant are at risk. It includes women with a higher chance of having an affected child. But one should not jump to abortion. All the tests show only the degree of risk, but cannot be the basis for diagnosis. Every woman has the opportunity to obtain a more accurate picture, having invasive tests.
Invasive surveys are shown in case of suspected down syndrome in the screening results. All methods based on the study of the tissues from the amniotic bubble. Amniocentesis, cordocentesis, chorionic villus sampling — the direction of all these tests gives a geneticist.
- Amniocentesis is one of the safest invasive surveys. Is assigned from 10 to 21 weeks of pregnancy. Under ultrasound control, make a puncture of the membranes and collect 10 ml of fluid from amniotic fluid. They contain all the chromosomes of the developing fetus. Discovered three 21st chromosomes will indicate the down’s syndrome 99%. The result is prepared from 3 days to three weeks.
- Cordocentesis — a study of umbilical cord blood. Prescribed 16 weeks. Under ultrasound guidance by inserting a needle into the umbilical cord, where we take 5 ml blood for examination. On the basis of the found in umbilical cord blood of three 21 chromosomes, the diagnosis is the presence of daunizm. Research accurate 98% -99 %. Usually associated with amniocentesis.
- The chorionic villus sampling examination of tissue from the placenta. Is assigned from 9 to 14 weeks. A puncture is made through the abdominal wall or through the cervix using a flexible probe. Results ready in 1 – 4 weeks. If the test material is found three chromosome 21 pair, the probability of down syndrome is equal to 99%.
Examination invasive methods for accuracy close to 100%. Despite this, to have an abortion or not should be decided by parents in consultation with a geneticist. Taking the decision, we must remember that abortion itself can deprive a woman to have children.
Unfortunately, there is no guarantee that certain actions will prevent the conception of a child with disabilities. But there is a chance to reduce its likelihood.
If pregnancy is planned, to be safe you can contact the medical-genetic consultation. Here expectant parents examine and determine if there are any signs for birth of child with abnormalities.
To protect yourself from chromosomal and genetic abnormalities, it is impossible to abuse alcohol, nicotine, drugs, and antibiotics. Do not use modified foods and foods with nitrates. Beware of radiation, viral diseases.
For the health contact your doctor for the treatment of diseases. It is not necessary to self-medicate. Athletic lifestyle will protect egg cells from oxygen starvation. It is important to monitor the quality of food and their weight. If the pregnancy was planned, then the best time for conception is the beginning of autumn. In this period, the body accumulates needed for child development trace elements.
The intake of folic acid, vitamins B and E prior to conception will help to normalize the body and organs responsible for reproduction.
But even if you have by coincidence all diagnoses show signs of down’s syndrome, do not rush to have an abortion. According to surveys of parents not having an abortion, more than 80% are glad to have left the child in the family. Massage, physical therapy and other treatments help the baby to adapt to normal life. Many children with the mosaic form of down syndrome are able to learn in school. They get along well with peers, receive education and profession. Sun child (and so they are called out of kindness, innocence and smiling) makes native people kinder and more cheerful.