Chorioamnionitis - An Overview

Introduction

Chorioamnionitis is an infectious condition affecting the membrane surrounding the fetus, the placenta, and the amniotic fluid. Placenta is an organ that develops within the uterus during pregnancy. It helps provide nutrients and oxygen to the fetus and removes waste products from the growing baby’s blood. Placenta gets attached to the uterine wall from which the umbilical cord arises. During pregnancy, a type of fluid surrounds the growing baby within the uterus called the amniotic fluid. Amniotic fluid provides a cushioning effect to the growing baby and acts as a medium for exchanging nutrients, gases, water, and other products. Chorioamnionitis is a serious condition leading to preterm labor.

What Is Chorioamnionitis?

Chorioamnionitis is an intra-uterine or intra-amniotic infection. It leads to preterm labor and delivery. The infection is caused when the causative bacteria enters the uterine tissues and affects the following components:

• Placenta.

• Amniotic fluid.

• Chorioamniotic membranes.

Chorion and amnion are the chorioamniotic membrane. The infection got chorioamnionitis due to the involvement of chorion and amnion. The chorion and amnion are the membranes that form the amniotic sac. Amnion is an avascular layer (a layer without any blood vessels) and surrounds the growing embryo. The chorion is the outer membrane surrounding the embryo covered by the other membranes.

What Are the Causes of Chorioamnionitis?

Chorioamnionitis is mainly caused when bacteria reach the placenta, amniotic fluid, and membranes. It mainly develops when the causative organism enters through the cervix or vagina of the expecting mother. The infection may initiate as one affecting the rectum, anus, cervix, and vagina. Chorioamnionitis may also be caused directly within the uterus when the amniotic sac tears or ruptures. It may also be caused by the procedure called amniocentesis, a medical assessment to check for genetic or chromosomal conditions in the baby. The doctor uses a thin needle that gets inserted into the uterus through the stomach wall for this procedure. Persistent and untreated urinary tract infections can also lead to chorioamnionitis or other pregnancy infections.

Vaginal and cervical infections can be due to the following reasons:

• Douching the vagina may lead to infection due to the contact of the inside of the vagina with certain fluids.

• Infections may also be due to unhygienic sexual intercourse.

• Sexually transmitted infections can lead to cervicitis or an infected cervix and cause chorioamnionitis.

• Allergic reactions affecting the cervix or vagina can progress to an infection leading to pregnancy infection.

• Transvaginal ultrasound scanning rarely causes infection during pregnancy.

What Are the Symptoms of Chorioamnionitis?

The symptoms of chorioamnionitis vary from one person to another. The following are some common symptoms of the condition:

• Fever.

• Tender uterus.

• Increased vaginal discharge.

• Excessive sweating.

• Bad-smelling vaginal discharge.

• Abdominal pain.

• Increased heart rate of the fetus.

• Altered color (yellow to green) of the vaginal discharge.

• Tachycardia or increased heartbeat.

• Itchiness around the vagina.

What Are the Complications of Chorioamnionitis?

Chorioamnionitis can cause complications or harm to both the mother and the baby. The following are the complications of chorioamnionitis:

• Bacteremia: Chorioamnionitis may cause bacteremia in the mother. Bacteremia is a condition due to the presence of bacteria in the blood. It is also called blood poisoning. Fever and chills are some major symptoms of the condition. Untreated bacteremia can be life-threatening.

• Preterm Delivery: Premature or preterm delivery is when the baby gets delivered before completing the full-term pregnancy period. It is the birth of the baby before 37 weeks of pregnancy. An earlier-born baby is susceptible to infections and serious diseases. Such babies will have a low birth weight and less immunity.

• Diseases in the Baby: Chorioamnionitis makes the baby more prone to infections or diseases like meningitis (infection and inflammation of the meninges), pneumonia, or even death.

• Infections: Chorioamnionitis can cause infections in the abdominal area or pelvis in the mother.

• Blood Clot Accumulation: Chorioamnionitis can lead to the formation and accumulation of blood clots in different areas of the body, especially the lungs or pelvis.

• Sepsis: Sepsis or septicemia is a life-threatening complication due to an underlying infection. Chorioamnionitis may lead to sepsis in both the mother and the baby. It is a medical emergency condition and requires immediate medical assistance.

What Are the Risk Factors of Chorioamnionitis?

The following factors increase the risk of development of an infection within the uterus during pregnancy:

• Smoking and alcohol consumption during pregnancy.

• Drug intake during pregnancy.

• Sexually transmitted infections like syphilis, HIV (human immunodeficiency virus) infection, trichomoniasis, chlamydia, gonorrhea, and others.

• Persistent bacteria vaginosis.

• Persistent urinary tract infections.

• Prolonged rupture of membranes when it takes more than 24 hours to fall into labor after water breakage.

• Premature labor.

• Long labor.

• Group B streptococcal infection.

• Frequent vaginal examinations done after water breakage.

• Intrauterine monitoring.

• Weak cervix.

• When the baby passes meconium (the baby's first feces) to the amniotic fluid.

How Is Chorioamnionitis Diagnosed?

The doctor will take a detailed history of the patient to know and understand the symptoms. They will also examine the patient closely for any visible signs. Blood or urine tests will help detect the presence of an infectious agent. In addition, the white blood cell count will help the healthcare provider know if there is an underlying infection. The vaginal discharge may be cultured to detect the presence of infectious bacteria. An ultrasound scanning helps see the condition of the mother and the baby. Carrying out an amniotic fluid sample examination will also be helpful. The amniotic fluid will be collected by a technique called amniocentesis.

How to Treat Chorioamnionitis?

The doctors will usually prescribe safe antibiotic medications to treat the infection. The intravenous or IV route is generally opted to administer antibiotics. The doctors may also encourage an early delivery, and the baby will be treated separately with antibiotics if they show symptoms of the infection. Early delivery will prevent complications in the baby. The mother will be encouraged to take the antibiotics after delivery.

Conclusion

Chorioamnionitis is an intrauterine infection during pregnancy. It affects the membranes, placenta, and the amniotic fluid. It majorly develops when the amniotic sac ruptures long before delivery. The mother may show symptoms like chills, fever, and decreased heart rate due to the infection. It can lead to complications in both the mother and baby. Intravenous administration of antibiotics is the primary treatment for the condition.