Embryotoxic action. The effect of drugs on the embryo and fetus

2024 Author: Priscilla Miln | [email protected]. Last modified: 2023-12-16 00:21

Every pregnant woman should be aware that any medication she takes will have an effect on the fetus, as many chemicals can cross the placenta to the developing baby. Their embryotoxic and fetotoxic effects often result in embryonic death, delayed skeletal development, reduced body weight gain, or increased perinatal pathologies.

Relevance of the problem

According to the study, approximately 1% of the development of fetal anomalies is associated with uncontrolled medication by the mother. Therefore, doctors and scientists around the world set the primary task of studying medicines and their effect on the body of a child in the womb and on the body of a pregnant woman. Different periods of pregnancy should be taken into account.

Many research centers are conducting studies on the embryotoxic and teratogenic effects of drugs on the embryo and fetus. Alsotheir fetotoxic effect on its development occurs.

Thus, the embryotoxic effect in pharmacology is the ability of a drug, when it enters the mother's body, to have a detrimental effect on the fetus, which leads to its death or developmental anomalies.

What is embolic action

Embryotoxic effect is the defeat of the non-implanted blastocyst, which often leads to its death. This effect is caused by drugs such as barbiturates, salicylates, athymetabolites, sulfonamides, nicotine and other similar substances.

Embryotoxicity means the effect of drugs from the mother's body on the embryo and fetus, which lead to its death or developmental abnormalities.

Teratogenic effect is the effect on the fetus of drugs or biological substances, which causes disturbances in the development of the fetus, and subsequently the child suffers from congenital deformities.

How do drugs affect the body of a child in the womb

Depending on the mechanism of action on the fetus of drugs, three directions can be distinguished:

• First - those that cross the placenta and are not able to have a direct effect on the developing body of the fetus.
• Second - through the transplacental transition, which means that they have a direct effect on the fetus.
• Third - those that, penetrating the placenta, tend to accumulate in the body of the unborn child.

It is worth noting that the toxicity of the drug does not affect how it enters the fetus.

Teratogenic embryotoxic effect on the fetus can have drugs not only those that a woman takes during pregnancy, but also the drugs that were used before conception. An example is retinoids, which are teratogens with a long latent period. Accumulating in a woman's body, they can further affect the development of the fetus.

And even taking medications by the father of a child can affect the congenital pathologies of the crumbs. Most often, these are the following medications:

• substances intended for anesthesia;
• antiepileptic drugs;
• "Diazepam";
• "Spironolactone";
• "Cimetidine".

Classification of drugs by pregnancy risk category

The US Food and Drug Administration - FDA, has developed a special classification of drugs that are most and least dangerous to the fetus during its gestation:

• A - these include medicines that are not able to affect the body of the mother and child. The ongoing research has eliminated this risk. B - drugs that can be taken in a limited amount, while subsequently no abnormalities in the development of the fetus were observed. Animal studies have ruled out any effect of these drugs on the growing body.inside the mother.
• C - these medications, when tested on animals, had a teratogenic or embryotoxic effect on the embryo. They harm the child's body, but have a reversible effect. Often, the development of anomalies in the fetus was not observed.
• D - drugs from this group lead to irreversible consequences and congenital anomalies in a child. When prescribing such drugs, the doctor must balance their benefits and subsequent risks for the child.
• X - this category of medicines is capable of causing persistent anomalies in the development of the fetus and congenital deformities, since there is a proven teratogenic or embryotoxic effect on both animals and humans. Their use during pregnancy is strictly contraindicated.

What causes the use of different groups of drugs during pregnancy

Here is the embryotoxic effect that various medications can cause in the fetus:

1. Aminopterin - the fetus can die in the womb. If this does not happen, then multiple anomalies of its development occur, mainly they affect the facial part of the skull.
2. Androgens - limbs do not grow well. The trachea, esophagus and cardiovascular system are damaged.
3. Diethylstilbestrol - changes in the sexual plan in a child, in girls it is adenocarcinoma of the vagina and changes in the cervix, in boys - pathological conditions of the penis and testicles.
4. Disulfiram - drug causes miscarriages, clubfoot and splittinglimbs in a child.
5. Estrogens - cause congenital heart defects, feminization in boys, vascular disorders.
6. Quinine - if the death of the fetus does not occur, then later the development of glaucoma, mental retardation, ototoxicity, anomalies in the development of the genitourinary system is possible.
7. Trimethadion-mental retardation, anomalies in the development of the heart and blood vessels, trachea and esophagus.
8. Raloxifene - disorders in the reproductive system.

These are just examples of embryotoxic effects, in fact, the list can be continued for a long time, since there are a lot of drugs.

Teratogenic drugs

These include:

1. "Streptomycin" - the drug causes deafness.
2. "Lithium" - leads to heart disease, goiter, hypotension, cyanosis.
3. "Imipramine" - neonatal distress syndrome, leg defects, breathing problems, tachycardia, urinary problems.
4. "Aspirin" - persistent pulmonary artery hypertension, various bleeding. Including intracranial.
5. "Warfarin" - convulsions and bleeding, which often lead to fetal death, embryopathy, atrophy of the optic nerves, developmental delay.
6. "Ethosuximide" - the appearance of the child changes, his forehead is set low. Appearance acquires Mongoloid features, dermoid fistula, mental and physical retardation,the presence of an extra nipple.
7. "Reserpine" - ototoxicity.
8. "Busulfan" - development occurs with a delay, as in the womb. So in the future, clouding of the cornea is observed.

Effect of alcohol on fetal development

In addition to the fact that there is a concept of teratogenic and embryotoxic effects of drugs on the embryo and fetus, we can note the negative impact of alcohol, tobacco and narcotic drugs.

A woman who consumes alcohol during pregnancy, even in small doses, risks not only her own he alth, but also the he alth of her child.

The most common complications include:

1. Miscarriages are twice as likely.
2. Slow birth process, which brings various complications in the future.
3. Other complications during childbirth.

Subsequently, the child may experience such negative manifestations:

• 1/3 children have fetal alcohol syndrome;
• 1/3 of cases have toxic prenatal changes;
• and only a third of children born will develop without any visible complications.

Fetal Alcohol Syndrome

He is characterized by three main qualities:

• delay in physical development;
• mental retardation;
• specific appearance characterized by narrow forehead, narrow palpebral fissure, short nose, microcephaly.

It is possible to prevent these consequences if notdrink alcohol while pregnant.

The consequences of alcohol syndrome in a child as it grows may be dulled, but will not completely disappear. Such a child is hyperactive, his attention is disturbed, which affects his social adaptation.

Also, aggressiveness, stubbornness, poor night's sleep can become characteristic features of such a child.

Embryonic action of tobacco (nicotine)

Tobacco negatively affects the development of the fetus, and not only when a woman smokes herself. If she is a passive smoker, that is, she is in a room next to people who smoke and inhales the smell of nicotine, she is already harming her unborn child.

Complications of this behavior include:

1. Vaginal bleeding.
2. Poor placental circulation.
3. The risk of delayed labor also increases.
4. Risk of spontaneous abortion and preterm birth.
5. Risk of placental abruption.

Smoking can affect the fetus in the following ways:

1. Slow fetal development, at birth these babies have low height and weight.
2. There is a risk of congenital anomalies.
3. The chance of sudden death of a newborn is doubling.
4. Subsequent developmental risks, this can manifest itself in mental and physical retardation, a tendency to respiratory diseases, unpredictability in the child's behavior.

Conclusion

The embryotoxic action of many medicinal and non-drug substances can lead to severe irreversible consequences. It is necessary to know before taking medicines that they will negatively affect the embryo or fetus. Therefore, on the part of doctors, young women are advised to take a responsible approach to the birth of a child, prepare for the birth process even before conception, read relevant literature, undergo regular examinations, and lead a he althy lifestyle.

Only under such conditions is there a chance to give birth to a he althy baby, without any deviations. Every time you try to take any drug, be aware of the embryotoxic effect of drugs, this may affect your unborn child. Therefore, discuss your every step with your doctor.