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Intraamniotic Infection

(Chorioamnionitis)

By

Julie S. Moldenhauer

, MD, Children's Hospital of Philadelphia

Reviewed/Revised Jan 2024
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Intraamniotic infection is infection and resulting inflammation of the tissues around the fetus, such as the fluid that surrounds the fetus (amniotic fluid), the placenta, the membranes around the fetus, the fetus, or a combination.

  • Intraamniotic infection increases the risk of problems in a pregnant woman and in the fetus.

  • Women usually have a fever and often have pelvic pain and a vaginal discharge.

  • Usually, doctors can diagnose the infection by doing a physical examination, but sometimes amniotic fluid must be analyzed.

  • Women are given antibiotics and medications to lower body temperature, and delivery is scheduled as soon as possible.

Risk factors for intraamniotic infection

Intraamniotic infection typically develops when bacteria from the vagina enter the uterus and infect the tissues around the fetus. Many different kinds of bacteria normally live in the vagina. Usually these do not cause a vaginal infection, but if they spread to the uterus, they can cause a uterine infection. Normally, mucus in the cervix, the membranes around the fetus, and the placenta prevent bacteria from causing infection. However, certain conditions can make it easier for bacteria to breach these defenses.

Intraamniotic infection is also more likely if

Rarely, infection occurs when internal fetal monitoring Fetal monitoring Labor is a series of rhythmic, progressive contractions of the uterus that gradually move the fetus through the lower part of the uterus (cervix) and birth canal (vagina) to the outside world... read more is done. For this procedure, doctors monitor the fetus by inserting an electrode (a small round sensor attached to a wire) through a woman’s vagina and attached to the fetus’s scalp.

Complications of intraamniotic infection

Intraamniotic infection can increase the risk of the following problems in the fetus or newborn:

Intraamniotic infection can cause as well as result from preterm delivery or preterm prelabor rupture of the membranes.

Intraamniotic infection can increase the risk of the following problems in a woman:

Symptoms of Intraamniotic Infection

Intraamniotic infection usually causes fever and often causes abdominal pain and a vaginal discharge that can be foul-smelling. The mother and fetus may have a rapid heart rate. However, some women do not have typical symptoms.

Diagnosis of Intraamniotic Infection

  • A doctor's evaluation

  • A complete blood count

  • Sometimes amniocentesis

Doctors do a physical examination and a complete blood count (which includes a white blood cell count).

An intraamniotic infection is suspected when women have a fever and at least one other typical symptom, such as a fast heart rate in the fetus or a foul-smelling discharge or an abnormally high white blood cell count in the woman. If the diagnosis is still unclear, doctors can remove a sample of the amniotic fluid and analyze it (amniocentesis Amniocentesis Prenatal testing for genetic disorders and birth defects involves testing a pregnant woman or fetus before birth (prenatally) to determine whether the fetus has certain abnormalities, including... read more ).

If preterm labor or prelabor rupture of membranes occurs, doctors consider the possibility of infection even if women do not have typical symptoms.

Treatment of Intraamniotic Infection

  • Antibiotics

  • Medications to lower body temperature

  • Delivery

Women with an intraamniotic infection are given antibiotics intravenously. They are also given medications to lower body temperature (preferably acetaminophen before delivery).

Delivery should not be delayed once the diagnosis is made.

Prevention of Intraamniotic Infection

If a woman has preterm prelabor rupture of the membranes, doctors do pelvic examinations only if necessary.

Doctors usually also give a woman antibiotics intravenously and by mouth to help the pregnancy last longer and reduce the risk of problems in the fetus.

Doctors screen pregnant patients for group B streptococcus at 35 to 37 weeks of pregnancy. People who screen positive are given antibiotics during labor.

Drugs Mentioned In This Article

Generic Name Select Brand Names
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
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