Congenital defect - what is it? You will learn the answer to the question from the presented article. In addition, we will tell you about what types of defects exist, why they develop and so on.
General information about congenital malformations
Defect is an abnormal development as wella set of any deviations from the normal (standard) structure of the human body that arise in the process of fetal development (less postpartum).
As a rule, such changes are formed underexposure to various internal and external factors (for example, hormonal disorders, heredity, germ cell inferiority, viral infection, ionizing radiation, lack of oxygen, etc.). From the second half of the twentieth century, specialists began to notice a significant increase in pathological changes. Most congenital malformations occur in people living in developed countries.
Probable causes
40-60% of people have reasons for these deviations.unknown. The term “sporadic birth defect” is used for such patients. This expression refers to an accidental or unknown cause, as well as a reduced risk of recurrence in a future generation.
For 20-25% of people, congenital malformationsare formed from a “multifactor” cause, that is, a complex interaction of genetic defects (more often small) or risk factors of the external environment. 10-13% of anomalies are associated only with environmental exposure. And only 12-25% of defects have exclusively genetic causes of development.
So, let us consider in more detail why certain people have congenital malformations.
Teratogenic factors
The effect of such factors depends on their dosage.The differences in teratogenic effects in different species can be related to the peculiarities of metabolism, absorption, the ability of a substance to cross the placenta and spread throughout the body.
The most popular and studied teratogenic factors
Malformation is most often observed in those who are exposed to the following effects:
- Infectious diseases that are transmitted frommother's fetus. A number of such viral diseases carried during childbirth, such as epidemic parotitis, rubella, or inclusion cytomegaly, may well contribute to the development of the disease.
- Alcohol. Of particular importance is the alcoholism of the parents, or rather, the mother. Drinking alcohol during pregnancy can easily lead to the formation of fetal alcohol syndrome.
- Ionizing radiation.Exposure to radioactive isotopes, as well as X-rays, can have a negative effect on the genetic apparatus. It should also be noted that radiation (ionizing) also has a toxic effect. This fact is the cause of most congenital anomalies.
- Medications. To date, there are no such medicines that would be considered completely safe for the fetus, especially in the first 2 trimesters of pregnancy.
- Nicotine. Smoking future mothers (during pregnancy) can quite easily lead to the fact that the child will lag behind in physical development.
- Nutrient deficiencies. Lack of nutrients (for example, iodine, myo-inositol, folate, etc.) is a proven risk factor for congenital heart defects and neural tube defects.
Consider such a common anomaly as a heart valve defect, in more detail.
Heart defects
Heart disease is a pathologicalchanges in valves, large intrathoracic vessels, as well as heart walls, as a result of which the normal movement of blood is disrupted. It should be noted that such deviations can be both acquired and congenital.
Most often, valvular heart disease occurs due toexcessive struggle of the immune forces of the human body with harmful microorganisms penetrated into it. Treatment of this deviation is reduced to the replacement of natural, but damaged valves, artificial by surgical intervention.
When a vice develops
This pathological phenomenon (any type) is most oftenformed during the period of embryonic morphogenesis (that is, at the 3-10th week). This fact is due to the fact that at this time the processes of reproduction, differentiation, migration and cell death are disrupted. Such phenomena occur at the interstitial, intracellular, interorgan, extracellular, organ and tissue levels.
Existing types
Congenital malformation is the widest categoryincluding completely different conditions: from minor physical anomalies (for example, large moles, birthmarks, etc.) to serious violations of individual systems (for example, valvular heart disease, limb defects, etc.). There are also combinational anomalies that affect several parts of the body at the same time. Metabolic defects are also considered congenital defects.
In medical practice, there are three main types of congenital malformations:
- congenital metabolic errors;
- congenital physical abnormalities;
- other genetic defects.
Frequency of occurrence
Long-term studies of congenital anomaliesshowed that a particular malformation of the fetus manifests itself with a certain frequency depending on the sex of the child. For example, club-shaped foot and pyloric stenosis are most common in boys, and congenital dislocation of the hip is in girls.
Among those children who were born with one kidney,more of the stronger sex. It should also be noted that most often such anomalies as the excessive number of ribs, teeth, vertebrae and other organs are found among newborn girls.
List of malformations
Today there are a huge number of vicesdevelopment. Most often, they are detected during an ultrasound examination of the mother. If the anomaly is serious enough, then the woman is offered to terminate the pregnancy. This is primarily due to the fact that a born child will be endangered all his life and feel inferior (depending on the type of anomaly).
Let's consider together what malformations exist:
- aortic defect;
- jejunal atresia;
- lung agenesis;
- acrania;
- bilateral renal agenesis;
- anencephaly;
- congenital dislocation of the hip;
- unilateral agenesis of the kidneys;
- esophageal atresia;
- congenital cloaca;
- albinism;
- VACTERL association;
- aplasia of the lung;
- cleft palate;
- atresia of the anus;
- club-shaped foot;
- Down's disease;
- congenital cretinism;
- congenital megacolon;
- congenital heart defects;
- hydrocephalus;
- hernia;
- lung hypoplasia;
- esophageal diverticula;
- syndactyly;
- polysomy on the X chromosome;
- Meckel's diverticulum;
- patau syndrome;
- cleft lip;
- polythelia;
- Klinefelter syndrome;
- cryptorchidism;
- genital malformations;
- clubfoot;
- Klippel-Feil syndrome;
- megacolon;
- feline cry syndrome;
- microcephaly;
- Shereshevsky-Turner syndrome;
- underdevelopment of the femoral and tibial bones;
- fetal alcohol syndrome;
- omphalocele;
- spinal hernia;
- fibrodysplasia;
- pyloric stenosis;
- polydactyly;
- Edwards syndrome;
- cyclopia;
- cranial hernia;
- bladder exstrophy;
- epispadias;
- ectrodactyly.
Let's sum up the results
As you can see, there are quite a few inborndefects that occur in the fetus in the prenatal period of development. To avoid the occurrence of such anomalies in your child, prospective parents should avoid exposure to factors contributing to their education. Thus, future mothers and fathers are advised not to drink alcoholic beverages 6–9 months before conception, and also not to use them during pregnancy (for women). In addition, you should quit smoking, avoid those places where there can be ionizing radiation, do not take medicines not prescribed by a doctor, visit the fresh air more often and take all the necessary vitamins and minerals.
