Chorioamnionitis is known as inflammation or an infection around the layers of the developing baby. This intrauterine inflammation triggers 40%โ70% of premature deliveries, putting both the mother and her fetus at risk of serious complications.
How does it happen?
The occurrence of acute chorioamnionitis happens due to ascending infection from the urogenital tract. The colonization of microorganisms ascends to endometrial space with extension into the fetal membranes, the amniotic fluid, and ultimately the fetus.
The causes of this infection are:
The most commonly occurring microorganisms are:
- Mycoplasma
- coli
- Group B Streptococcus (GBS)
- Ureaplasma
- Fungi such as Candida
Several women who become pregnant while using intrauterine contraceptive devices have reported Intrauterine infection with fungi. In addition, there are various TORCH pathogens, including Toxoplasma Gondi, Rubella, Cytomegalovirus, and Herpes viruses 1 and 2, which have been implicated in chorioamnionitis.
The non-infectious causes are:
Microorganisms such as bacteria and fungi are frequently associated with chorioamnionitis. However, it can also occur as sterile intra-amniotic inflammation. Sterile inflammation has no presence of microorganisms and is rather induced by cellular stress, injury, or death.
The symptoms of chorioamnionitis are:
It can affect almost every organ of the developing fetus, leading to clinical syndrome with any combination of the following symptoms:
- Fever with elevated WBC count
- Maternal or fetal tachycardia
- Uterine tenderness
- Foul-smelling amniotic fluid
Intrauterine management:
Antibiotics, progesterone and corticosteroids are used in the treatment of chorioamnionitis. Sometimes due to the persisting inflammation, there can be a fetal and maternal injury. In such cases, the antibiotics fail to prevent the morbidities associated with chorioamnionitis. Exposure to chorioamnionitis activates the fetal immune system in the uterus, leading to long-term health consequences after birth.
What are the neonatal complications involved?
Chorioamnionitis increases the risk of morbidity and mortality by 2-4% for the developing fetus.
The following are the main complications:
- Early onset neonatal sepsis
It is categorized by the positive blood, urine, or spinal fluid cultures along with clinical symptoms within 72 hours after birth. Respiratory distress and poor Apgar scores are the clinical hallmarks, raising the need for resuscitation within 30 minutes after birth. A study was conducted on the ‘prevalence of chorioamnionitis and an associated early onset sepsis’ in the United States. The analysis of 9391 mother-infant pairs data showed that the frequency of chorioamnionitis was found to be 10.3%, while infants with early-onset sepsis were 6.6%. The most isolated organisms in confirmed cases of sepsis were Group B Streptococcus (GBS) and Escherichia coli.
- Preterm labor
Chorioamnionitis is strongly linked to preterm labor due to the presence of inflammatory mediators such as Interleukin-1 (IL-1). Preterm birth exposes the infant to many possible complications, such as neonatal sepsis, pneumonia, perinatal death, cerebral palsy, and intraventricular hemorrhage. In short, prematurity is a major cause of neonatal mortality and morbidity.
- Respiratory distress syndrome (RDS)
Respiratory distress syndrome is more evident in preterm infants infected by chorioamnionitis and delivered before 37 weeks of gestation. In chorioamnionitis, fetal breathing leads to the mixing of fetal lung fluid with amniotic fluid, resulting in potential fetal lung exposure to microorganisms.
- Neurological deficit:
Multiple epidemiological studies have linked perinatal brain injuries such as cerebral palsy, autism & schizophrenia to chorioamnionitis. Inflammatory cytokines released during chorioamnionitis have been suggested as a possible cause of cerebral injury.
An insight from mamahood
Chorioamnionitis is commonly used to denote clinical suspicion of intra-uterine inflammation or infection, even before any pathological or laboratory evidence. Sometimes, the test findings are neither conclusive nor aligned with the clinical symptoms. Unfortunately, it is difficult to diagnose the uterine infection promptly until the baby is delivered. In an effort to develop better treatment strategies for infants born to mothers with chorioamnionitis, a better understanding of inflammatory processes is needed during pregnancy.
