Infections during pregnancy and their significance

Infections during pregnancy are extremely important for the health of both the mother and the baby. It is well known that even the healthiest human body is not sterile — billions of bacteria, cocci, fungi, and other microorganisms live in the intestines, respiratory system, urogenital tract, and other systems.
The immune system of an adult strictly controls their activity. A healthy person usually does not think about this relationship unless it is a pregnant woman.

During pregnancy, even asymptomatic infections become particularly significant. Not to mention infections occurring at different stages of pregnancy. The situation is complex: if a woman carries pathogenic microorganisms, intrauterine infection of the fetus is possible and may lead to adverse pregnancy outcomes.

However, the risk is not always as high as many expectant mothers believe. Normally, the fetus is protected by the immune system and placenta. When these barriers fail, intrauterine infection occurs.

Infection can be transmitted to the fetus in two main ways: hematogenous and ascending.

In the hematogenous route, pathogens enter the placenta through maternal blood and then reach the fetus via the umbilical cord. In ascending infection, microorganisms move from the genital tract into the uterus, infect the membranes, and enter the fetal body through amniotic fluid.

The outcome depends on gestational age, maternal immunity, and microbial characteristics.

Severe infection in early pregnancy (5–12 weeks) often leads to fetal loss or miscarriage due to developmental abnormalities or placental dysfunction.

Some infections may cause developmental defects compatible with life but difficult to treat after birth. Rubella virus is a known example.

Infections in later stages usually do not cause major malformations but may lead to inflammation and increase the risk of preterm birth.

It is important to understand that most microorganisms do not cause severe fetal abnormalities in mild infections.

Dr. Irina Ergül will provide diagnosis and appropriate treatment if needed.

Below we will review common pathogens causing intrauterine infections.