TERATOGENICITY AND MEDICATIONS AFFECTING THE FETUS (Part seven)

14 - Infectious agents

- Their action on the embryo or fetus involves mitotic inhibition, direct cytotoxic effects, vascular disorders.

- The healing process may be accompanied by the formation of striae or calcification.

*Varicella

- 85-95% of pregnant women are immune to this disease, so exposure during pregnancy means the woman does not get affected by the disease.
- The disease is caused by the varicella zoster virus, which belongs to the herpes viruses.
- Transmission occurs from one person to another through direct contact or air.
- It is contagious 1-2 days before the appearance of blisters until they dry up.
- To develop the disease, it takes 14-18 days from exposure to the appearance of symptoms.
- When the infection affects the woman in the first 20 weeks of pregnancy, there is a 2% chance that the child will be affected by congenital varicella syndrome which includes: spots, defects in muscles and bones, malformed and paralyzed limbs, small head, blindness, contractions, mental delay.
- They are rare after the 20th week of pregnancy.
- Risky period is 5 up to 2 days before, 25-50% of children are affected and develop rash within 5-10 days after birth. If these children are not treated, 30% of cases will die.
- If the mother develops a rash within 6-21 days before birth, the child shows some problems in the face.
- If the baby is treated immediately after birth with varicella immune globulin, the severity of the disease is prevented or reduced.
- All pregnant women should avoid contact with people infected with the disease.

*Syphilis

- It is believed that the fetus is not affected by syphilis early in pregnancy because the cytotrophoblast layer of the chorionic villi of the placenta prevents the passage of the spirochete from the mother to the fetal blood.
- This protection disappears after the sixth month of pregnancy.
- It does not cause spontaneous abortions in the first trimester of pregnancy except for syphilitic endometritis.
- In the third trimester, it causes preterm birth, congenital syphilis, normal fetus, or death within the first 4 weeks of birth.

*Toxoplasmosis

- It is an infection caused by Toxoplasma gondii.
- Occurs 1:1000 pregnancies.
- In a fetus affected by the infection, hydrocephalus, microcephaly, cerebral calcifications, chorioretinitis leading to blindness, hepatitis, and lymphadenopathy are noted.
- If the woman is affected for the first time, the risk of the fetus being affected reaches up to 30%.
- The earlier the infection occurs, the more severe are the consequences.

- Infection can be caused by: coming into contact with cat feces that contain parasites, eating contaminated food or drinking contaminated water, knives or tools that come into contact with contaminated meat, eating unwashed and contaminated fruits or vegetables, transplant of contaminated organs, transfusion of contaminated blood.

- Those most at risk are people with a compromised immune system, treatment with immunosuppressants, corticosteroids, chemotherapy, affected by HIV/AIDS.

- Diagnosed by evaluating toxoplasmosis antibodies (IgM, IgG), amniocentesis, morphological ultrasound, and in more severe cases MRI, brain biopsy.

- Treatment of a pregnant woman affected by the disease and an unaffected fetus is spiramycin, whereas when the fetus is also affected by the disease, pyrimethamine and sulfadiazine are used. This medication shows many side effects and is used only in extreme cases.

15 - Temperature disorders

*Hyperthermia

- Exposure to a temperature above 38.9°C has an antimitotic teratogenic effect when the embryo is exposed from the first 4-14 weeks.
- Severe mental deficit, seizures, microphthalmia, hypoplasia of half of the face, distal limb anomalies, hypotonia, dysgenesis of the central nervous system, occipital encephalocele are noted.

*Hypothermia

- Exposure to a body temperature less than 35 °C.
- Hypoperfusion is associated with brain and spinal cord injuries.

15 - Statins

- Statins are hypolipidemic drugs used to lower serum cholesterol levels in people who are or are at high risk for cardiovascular diseases.
- Cholesterol is a component of cell membranes and very important in the embryonic and fetal phase.
- Cholesterol is a precursor of important steroid hormones in fetal development and particularly in brain development.
- Included in drug category X.
- Contraindicated in pregnancy or in a woman planning a pregnancy.
- A wide range of congenital anomalies associated with the lack of cholesterol synthesis is known, skeletal dysplasia, dermatological disorders, chondrodysplasia punctata type II, congenital hemidysplasia, limb anomalies.
- Many studies suggest that statins have a teratogenic effect.

16 - Antimalarial

*Chloroquine

- A drug used as a first-line for prophylaxis and treatment of malaria, in high doses it is also used for the treatment of rheumatoid arthritis and systemic lupus erythematosus.
- Known as a drug with teratogenic action.
- Damage in pregnancy depends on the dose of exposure and the age of pregnancy.
- The most common problems are: spontaneous abortion, preterm birth, low birth weight, intrauterine growth retardation, in utero death, jaundice, anemia, liver enlargement.

Conclusion:

- It is important to take a careful history, to determine the medications used and the various substances of exposure of a woman who is pregnant or planning a pregnancy in order to determine the risks of pregnancy and the precautionary measures to be taken.

- To determine the risks against the benefit of using medications in different diseases.