top of page

Teratogenic Groupings

Biological Teratogens

how do viruses affect the baby

Biological teratogens are infections, viruses, bacteria, or other living organisms that can interfere with normal fetal development during pregnancy. These biological agents may cross the placenta or affect the mother’s immune and metabolic systems, potentially causing developmental abnormalities, neurological damage, growth restriction, or pregnancy complications.The developing fetus is particularly vulnerable during the first trimester, when major organs and body systems are forming. The severity of harm often depends on the type of infection,  the timing of exposure,

                                                                                                                                                                       and the body’s immune response.

​​

​

​

​

Certain viruses are known to increase the risk of fetal abnormalities, including:

​

  • Rubella (German measles)

  • Cytomegalovirus (CMV)

  • Zika virus

  • Varicella (chickenpox)

  • Herpes simplex virus

​

These infections may affect brain development, hearing, vision, growth, and neurological function.

​

Bacterial Infections

​

Some bacterial infections may also disrupt fetal development or pregnancy health, including:

​

  • Syphilis

  • Listeriosis

  • Tuberculosis

​​

These infections can increase the risk of miscarriage, stillbirth, premature birth, or congenital abnormalities#

.

Parasitic Infections

​

Parasitic organisms such as Toxoplasma gondii can affect fetal brain and eye development if transmitted during pregnancy.

​

​

​

Biological teratogens may harm fetal development through several mechanisms, including:

​

  • Direct infection of fetal tissues

  • Inflammation and immune activation

  • Fever and metabolic stress

  • Reduced oxygen or nutrient supply

  • Damage to rapidly developing cells

​​

In some cases, the body’s inflammatory response to infection may contribute to developmental complications.

​

Prevention and Awareness

​

​

Modern healthcare has greatly reduced the risks of many biological teratogens through:

​

  • Vaccination

  • Prenatal screening

  • Infection control

  • Improved nutrition and healthcare access

  • Early diagnosis and treatment

​​

Awareness of biological teratogens remains important in protecting maternal and fetal health and supporting safer pregnancies worldwide.

common biological teratogens

Biological stress and foetal development

bottom of page