Reasons for having children with Down syndrome24.05.2022
For every 700 newborns in the world, there is one child with Down syndrome. The causes of the appearance of pathology in children is considered a mutation in chromosome 21. Normally, a person has 46 chromosomes, that is, 23 pairs. When a mutation occurs, an extra chromosome 47 appears.
The main factor why children with Down syndrome are born is the age of the woman in labor. The older the woman, the higher the likelihood of the birth of a “sunny baby”. Statistics indicate the following pattern of risk depending on the age of the woman in labor:
- from 20 to 25 years old – 1 baby with the syndrome out of 1500;
- 25-35 years old – 1 out of 1000;
- 35-45 years old – 1 out of 250;
- 45 years old – 1 out of 19.
Under the age of 20, the risk of having a baby with 47 chromosomes is as high as in forty-year-old women. In young girls, the maturation of germ cells is unstable, which does not have the best effect on the process of chromosome formation.
The age of the man is also important. Most children with the syndrome are born in men after 42 years.
Such statistics can hardly be called completely objective, since women most often give birth to their first child under the age of 35. And among a large number of newborns, the percentage of “sunny children” is lower.
Not only age affects the increased risk of having children with Down syndrome. There are other factors for the development of the anomaly:
- marriages between close relatives;
- one of the parents is a carrier of the Down syndrome gene and has relatives with an increased set of chromosomes.
Despite the above reasons, it is difficult to determine the pattern of the birth of such babies. Often, chromosome disorders are observed in children with perfectly healthy young parents without bad habits and bad heredity.
Scientific explanation of the development of pathology
Down syndrome is a disorder of the set of chromosomes. A healthy person has 46 of them. Children with the syndrome have 47. No one is immune from the risk of having a “sunny baby”, because even healthy parents sometimes have special children. And no one is to blame for this, it’s just that circumstances developed, that’s how nature formed the baby in the womb.
In a pair, an extra chromosome appears due to one of the following reasons:
- during cell division of the egg and sperm, the paired chromosome did not separate;
- after fertilization, the process of cell division is disrupted;
- the mutation was passed down from one of the parents.
There are several forms of anomaly:
- Trisomy of 21 pairs, which appears in the process of division of germ cells due to non-disjunction of chromosomes. The degree of pathology is different. This is the most common form.
- Mosaic syndrome – the divergence of chromosomes was noted already at an early stage of embryo development. In this case, not all cells have an extra chromosome. The form of pathology is mild.
- Translocation form – chromosome 21 pair is attached to another pair. This pathology depends on hereditary factors and usually manifests itself if one of the parents has family members with Down syndrome.
Doctors are able to determine Down’s syndrome already in the early stages. And a woman can terminate a pregnancy if she is not ready to give birth and raise a special baby. But children with Down syndrome are not a punishment for mom and dad. The kid will bring a lot of joy to his parents. “Sunny people” get an education, find a job and easily fit into society, especially with the reliable support of loved ones. They suffer not from an atypical set of chromosomes that nature has awarded them, but from a prejudiced attitude on the part of others, not perceiving them as full-fledged members of society.
Read more: Fetal Alcohol Syndrome in Children