Maternal fever (intrapartum temperature > 37.8°C) is the most common symptom of chorioamnionitis. Other characteristic features of the disease are fetal tachycardia, purulent amniotic fluid, uterine tenderness and maternal leukocytosis. When two or more of these symptoms are observed in the patient, the risk of neonatal sepsis increases.

Though in some cases, the pregnant women with chorioamnionitis may show no signs or symptoms, in some cases, they may appear ill, even toxic and hypotensive with cool or clammy skin. The symptoms of the suspected sepsis in the neonate and mother are often nonspecific and include findings such as behavioral abnormalities, tachypnea, cyanosis, apnea, pulmonary hemorrhage, tachycardia, vomiting and diarrhea, abnormalities in thermal regulation, pallor, overt bleeding and hypotension [7] [8].

Laboratory tests

• For asymptomatic pregnant women presenting preterm labor, the following tests must be performed namely examination of amniotic fluid, maternal blood and urine analysis, maternal blood group-B streptococcal screening. 
• Tests for febrile pregnant women with suspected chorioamnionitis include complete blood count, C-reactive protein, Alpha1-proteinase inhibitor complex, and serum interleukin-6 levels. 
• Evaluation of the amniotic fluid are bacterial cultures, Gram staining, pH levels, leukocyte count, levels of glucose in the blood, polymerase chain reaction, proteomic profiling, etc. 
• Other diagnostic tests for early onset neonatal sepsis are determination of the levels of procalcitonin, serum interleukin-6 or cytokine, bacterial antigen detection in the blood, etc. [9]

Imaging

Since short cervix is a risk factor for chorioamnionitis, ultrasonography can help to detect this altered anatomy. Imaging studies helps to ascertain the health of the fetus on a regular basis [9].

Therapy of chorioamnionitis includes early delivery and supportive care with the use of safe antibiotics. Some of the antibiotics to manage the disease are crystalline penicillin G, clindamycin, ampicillin, gentamicin, and cefotaxime.

Supportive care of the neonates are providing warmth, full resuscitation when needed, treatment of hypervolemia, respiratory acidosis, surfactant replacement therapy, glucose homeostasis and monitoring of the vital signs. Assessment of the thrombocytopenia is one of the important aspects that need to be looked into.

Some surgical options are also available for early onset bacterial infections in the neonate; however, they are rarely used. The conditions that warrant the surgical intervention are epidural and subcutaneous abscess, infections located in the pleural space, bone and joint infections, and similar conditions [10].

The long-term prognosis for both the mother with chorioamnionitis and the neonate is excellent. The fertility of the women is not compromised. The child born preterm may, however, suffer from the long-term complications such as neurologic impairment and chronic lung disease [11].

Complications

Some of the complications of chorioamnionitis are infection in the abdomen and pelvic regions, endometriosis, sepsis, and blood clots in the pelvis and lungs. Complications from bacterial infection in the newborn also include sepsis, meningitis and respiratory problems [12].

When the protective mechanism of the maternal urogenital tract fails during pregnancy, there is an increase in the indigenous microbial flora or influx of highly pathogenic microorganisms in the urogenital region. In pregnant women, therefore, urogenital hygiene is important. When the microorganism reach the placenta, it leads to infection. Short cervix, bacterial virulence factors and toxin production are some of the risk factors of this disease. In healthy pregnant women, bacteria such as lactobacilli, is a natural antibiotic of the vagina and cervix, and phagocytes also help to prevent infection.

However, in women with chorioamnionitis, this host protection is compromised. Oral and rectal hygiene is therefore extremely important for normal urogenital colonization. Some of the clinical events associated with chorioamnionitis are history of preterm labor or premature birth, and premature or prolonged ruptured fetal membranes. Evidences also suggest that epidural anesthesia may be associated with maternal fever or fetal tachycardia [2] [3].

In underdeveloped countries, the main reason for chorioamnionitis is the premature rupture of the membranes, which is often associated with a high mortality rate. In Africa, malnourished pregnant women are at a higher risk of having ascending urogenital infection causing chorioamnionitis.

This is believed to be due to decrease in the host defense factors. In developed countries, women receive optimum care during pregnancy with proper nutrition; hence the incidence of infection is greatly reduced [4].

• Abnormal bacterial colonization: Due to the abnormal colonization in the distal colon, abnormal vaginal and cervical microbial environments are created. Studies have confirmed that there are types of bacteria, which may ascend and rupture the fetal membrane and initiate the infection in amniotic fluid of the fetus causing chorioamnionitis. 
• Urinary tract infection leads to an easy access of the bacterial pathogen to the vagina, increasing the risk of neonatal sepsis. 
• Premature labor is associated with bacterial vaginosis. Early screening and treatment of vaginosis may prevent the preterm birth. 
• Some other causes of the condition are related to cervical insufficiency, release of vaginal prostaglandins, etc. [5] [6]

• Urinary tract infections, if diagnosed, must be treated immediately. 
• Risk of preterm labor must be determined at the earliest. 
• Chances of development of chorioamnionitis can be reduced by regularly attending the prenatal check-up, preventing bacterial vaginosis, practicing safe sex, and getting the routine vaginal culture done, when indicated.

Chorioamnionitis is a common complication of pregnancy. It is often associated with maternal fever and other long-term adverse outcomes such as postpartum infections, sepsis, premature birth, neonatal sepsis, brain injury and stillbirth, cerebral palsy and neurodevelopmental disabilities.

There exists a mechanistic relationship between the intraamniotic infection and preterm delivery. Ongoing research in the field has provided evidence for better methods of diagnosis, prevention and treatment of the condition [1].

Definition

Chorioamnionitis is a common complication of pregnancy which is associated with maternal fever and long-term adverse outcomes such as sepsis, brain injury, and stillbirth. Recent research provides better evidence of diagnosis, prevention and treatment of the condition. 

Cause

Abnormal bacterial colonization, urinary tract infection, premature labor associated with bacterial vaginosis, cervical insufficiency and release of vaginal prostaglandins are some of the important causes of chorioamnionitis. 

Symptoms

Some of the symptoms associated with this disease are maternal fever, illness, low blood pressure, and clammy skin.

Diagnosis

• For pregnant women who are asymptomatic, laboratory tests such as examination of amniotic fluid, maternal blood, and Group-B streptococcal screening and urine analysis are performed. 
• For the febrile pregnant women with suspected chorioamnionitis, complete blood count, C-reactive protein, Alpha1-proteinase inhibitor complex, serum interleukin-6 levels is done. 
• Tests such as bacterial cultures, Gram staining, pH levels and polymerase chain reaction, ultrasonography may also be performed. 

Treatment

Women with chorioamnionitis are treated with antibiotics such as clindamycin, ampicillin, gentamicin, and cefotaxime. Supportive care of the neonates such as providing warmth, full resuscitation, glucose homeostasis and monitoring of the vital signs is important. Assessment of the thrombocytopenia is one of the important aspects that need to be looked into. Some surgical options are available for early onset bacterial infections in the neonate; though, they are rarely used.

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