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by Cote S
(Amnionitis; Chorioamnion Infection; Intra-amniotic Infection)


Chorioamnionitis is an infection. It occurs in the membranes that surround the fetus. These membranes are called the chorion and the amnion. It is also an infection of the amniotic fluid. This fluid surrounds the fetus and protects it.

Chorioamnionitis can be a very serious condition. It requires special care from the doctor. A pregnant woman will need to deliver her baby right away. This is for the health of both the mother and the baby.

Birthing Complications: Intrauterine (Uterine) Infection
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Bacterial infections usually cause this condition. Infection may begin in the mother’s genital tract. Bacteria then move up from the vagina, through the cervix, and into the fetal membranes. It then moves into the amniotic sac and its fluid. There it can then pass to the fetus. Many types of bacteria may cause this infection.

Risk Factors

Chorioamnionitis is more common in young women. Other factors that can increase your chance of developing chorioamnionitis include:


Symptoms may include:

  • Fever
  • Increased heart rate in both the mother and the fetus
  • Tender uterus
  • Discharge with odor from the vagina


Your doctor will ask about your symptoms and medical history. A physical exam will be done. Your bodily fluid may need to be tested. This can be done with blood tests or amniocentesis.

The fetal heart rate will be monitored. The heart rate will increase if the mother has an infection.



The baby will need to be delivered. A cesarean section may be needed if:

  • Vaginal delivery would take too long
  • Mother shows signs of worsening illness
  • Baby shows signs of distress


Antibiotics will be delivered through an IV in the mother. The baby will get antibiotics if there is an infection present after birth.


To help reduce your chance of developing chorioamnionitis:

  • Attend regular prenatal check-ups. Call your doctor if you have any questions or concerns.
  • Get tested for GBS. This routine vaginal culture is done during your 35th-37th week.
  • Take steps to prevent bacterial vaginosis. For example, practice safe sex. Do not use douches or feminine sprays.
  • Tell your doctor right away if you have premature rupture of the membranes.


American Pregnancy Association 

The American Congress of Obstetricians and Gynecologists 


The Society of Obstetricians and Gynaecologists of Canada 

Women's Health Matters 


American College of Obstetricians and Gynecologists. ACOG Practice Bulletin No. 120: use of prophylactic antibiotics in labor and delivery. Obstet Gynecol. 2011;117(6):1472-1483.

Alanen A. Polymerase chain reaction in the detection of microbes in amniotic fluid. Ann Med. 1998;30(3):288-295.

Apgar BS, Greenberg G, Yen G. Prevention of Group B streptococcal disease in the newborn. Am Fam Physician. 2005;71(5):903-910.

Bacterial vaginosis (BV). EBSCO DynaMed Plus website. Available at: . Updated January 16, 2017. Accessed April 7, 2017.

Bacterial vaginosis—CDC fact sheet. Centers for Disease Control and Prevention website. Available at: Updated February 16, 2017. Accessed April 7, 2017.

Centers for Disease Control and Prevention. Prevention of perinatal group B streptococcal disease. MMWR. 2002;51:13-15.

Chorioamnionitis. Cleveland Clinic Health Information Center website. Available at: Accessed April 7, 2017.

Churgay CA, Smith MA, Blok B. Maternal fever during labor—what does it mean? J Am Board Fam Pract. 1994;7(1):14-24.

Edwards RK. Chorioamnionitis and labor. Obstet Gynecol Clin North Am. 2005;32(2):287-296.

Greenwald J. Premature rupture of the membranes: diagnostic and management strategies. Am Fam Physician 1993;48(2):293-306.

Protect your baby from group B strep. Centers for Disease Control website. Available at: Updated July 11, 2016. Accessed May 3, 2015.

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