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inflammation of the fetal membranes, most commonly due to bacterial or viral infection. It is usually the result of upward spread of vaginal organisms. Rupture of the amniotic membranes for over 24 hours before birth and prolonged labor are major predisposing factors. If the infection occurs when membranes are intact, it can result from ascending infections, from herpes, cytomegalovirus infection, or syphilis, or as a consequence of diagnostic amniocentesis.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Infection involving the chorion, amnion, and amniotic fluid; usually the placental villi and decidua are also involved.
Farlex Partner Medical Dictionary © Farlex 2012


Obstetrics Infection of the amniotic sac and villi Clinic High fever, prolonged rupture of membranes, prematurity, and ↑ fetal M&M
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


Infection involving the chorion, amnion, and amnionic fluid; usually the placental villi and decidua are also involved.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


DRG Category:765
Mean LOS:4.8 days
Description:SURGICAL: Cesarean Section With CC or Major CC
DRG Category:775
Mean LOS:2.4 days
Description:MEDICAL: Vaginal Delivery Without Complicating Diagnoses

Chorioamnionitis, or intra-amniotic infection (IAI), is an infection of the chorion, amnion, and amniotic fluids that surround the fetus and is characterized by monomorphonuclear and polymorphonuclear leukocytes invading the membranes. Leukocytes in the membranes are maternal in origin; leukocytes in the amniotic fluid (amnionitis) or in the umbilical cord (funisitis) are fetal in origin. Subsequently, the fetus also becomes infected. Chorioamnionitis, which can occur with subtle or acute signs and symptoms, can happen at any time during the prenatal or intrapartal period. It occurs in 0.5% to 10% of all pregnancies and 0.5% to 2% of term pregnancies, most commonly after premature rupture of the membranes. Chorioamnionitis can also cause premature rupture of the membranes and preterm labor. If left untreated, it can lead to maternal sepsis or fetal demise. In fact, chorioamnionitis is associated with a neonatal mortality rate of 1% to 4% for term infants and up to 10% for preterm infants.

The prognosis for the mother with chorioamnionitis is good. Once the baby is delivered, the source of infection is removed. Rarely does chorioamnionitis lead to septic shock. Occasionally, pelvic inflammatory disease can develop if the infection is not totally resolved. The prognosis for the infant varies depending on the degree of infection that is transmitted to the fetus. Occasionally, no signs of infection develop in the infant, but this is not typical. Another factor involved in the infant’s prognosis is prematurity; for the very premature infant, the risk of respiratory distress syndrome may be even greater than the risk of infection.


Chorioamnionitis is usually caused by bacteria that inhabit the genital tract. Less frequently, it can result from pathogens that cross over from the maternal circulation to the amniotic sac. Rarely, it is caused by the descent of pathogens from the abdominal cavity through the fallopian tubes. Commonly identified pathogens that contribute to chorioamnionitis are Escherichia coli, Streptococcus faecalis, Neisseria gonorrhea, group A and B streptococci, Chlamydia trachomatis, and Staphylococcus aureus.

Predisposing factors that contribute to chorioamnionitis include poor maternal nutritional status, history of drug abuse, history of multiple sexual partners, premature or prolonged rupture of membranes, sexually transmitted infections (STIs), the placement of a cerclage (ligature around the cervix to treat cervical incompetence during pregnancy), chorionic villi sampling, intrauterine transfusion, amniocentesis, mechanical cervical ripening for labor induction, and repeated vaginal examinations during labor.

Genetic considerations

Although it is not strictly a genetic problem, genetic variants in the cytokine tumor necrosis factor-α have been associated with an increased risk of chorioamnionitis and fetal morbidity.

Gender, ethnic/racial, and life span considerations

Chorioamnionitis can occur with any pregnancy regardless of the age of the mother. Pregnant teens may be more at risk because they have a high incidence of bacterial vaginosis, urogenital infections, and STIs. Ethnicity and race have no known effects on the risk for chorioamnionitis.

Global health considerations

Countries in North America and Western Europe have relatively similar incidence rates. Chorioamnionitis prevalence is higher in developing nations with high prevalence of HIV-infected women than in countries with low prevalence of HIV infections. In developing countries such as India and China, the prevalence of group B streptococci infections is lower than in developed Western countries for unknown reasons.



Ask about the last menstrual period to determine the estimated date of delivery and the gestational age of the fetus. Inquire about any past history of vaginal infections or STIs. Question the patient about the presence of any perineal pain, burning, malaise, or chills. Ask the patient if she is feeling contractions or if she has noted any leakage of the amniotic fluid. If the amniotic sac has ruptured, determine the time it occurred, the color of the fluid, and if the patient noted any odor. Also consider any prenatal tests or procedures, such as placement of a cerclage, chorionic villi sampling, intrauterine transfusions, or amniocentesis, that can predispose the patient to developing an intrauterine infection.

Physical examination

While not all patients will have symptoms, they may experience signs of infection such as abdominal tenderness, malaise, fever, tachycardia, and foul vaginal discharge. Early clinical findings in patients with chorioamnionitis may be vague. IAI can be present with no symptoms, and subclinical IAI may be three times more common than IAI with clinical symptoms. Assess the patient’s vital signs; patients with chorioamnionitis often display an elevated pulse above 120 beats per minute and temperature above 100.4°F. Palpate all quadrants of the abdomen for tenderness, noting the maternal response during examination of each quadrant. Foul odor of the vaginal discharge, color change of amniotic fluid from clear to light yellow to green, and an increase in the purulence of vaginal drainage are all consistent with chorioamnionitis.

Often, preterm labor patients with undiagnosed chorioamnionitis have contractions that do not respond to routine treatments of intravenous hydration and tocolytic therapy. Evaluate the baseline fetal heart rate. Fetal tachycardia, a heart rate above 160 beats per minute; a decreased fetal heart rate, a heart rate below 110 beats per minute; or decreased variability may be present with chorioamnionitis.


Increased anxiety is usually present with patients who are experiencing preterm labor, premature rupture of membranes (PROM), or a history of a cerclage placement. Assess the patient’s understanding of the situation and encourage the patient to express her fears. Also include an assessment of the patient’s social support and the response of significant others to the patient’s condition.

Diagnostic highlights

General Comments: Diagnosis may be difficult to establish early on because symptoms are vague. Examination of amniotic fluid is definitive.

TestNormal ResultAbnormality With ConditionExplanation
Amniocentesis or endocervical cultureNo growthGrowth of infecting organismCulturing the amniotic fluid will reveal the presence of a causative organism, allowing for appropriate choice of antibiotic therapy

Other Tests: Complete blood count with differential, C-reactive protein, group B streptococcal screening, fetal ultrasound, urinalysis, postpartum histological examination of the placenta

Primary nursing diagnosis


Infection related to microorganism invasion of sterile areas


Risk control


Medication management; Labor induction; Cesarean section care

Planning and implementation


The medical management of a patient diagnosed with chorioamnionitis is delivery of the infant, regardless of the gestational age. Thus, the current recommendation is to induce labor on all term patients presenting with PROM to decrease the incidence of chorioamnionitis. Delivery benefits the mother by emptying the uterus of all infected material. Once delivered, the infant can then receive the necessary antibiotic therapy and supportive care. Usually, spontaneous labor occurs because of the infection. If an adequate contraction pattern and progressive dilation of the cervix are not noted, contractions can be induced by oxytocin (Pitocin). Broad-spectrum antibiotics administered during labor cross the placenta and achieve peak levels in the fetal circulation within an hour after parenteral administration to the mother. Cesarean section is typically avoided because of the increased risk of spreading the infection; however, if the fetus is showing signs of distress, a cesarean section is performed. If the fetus is preterm, arrange for a neonatologist or pediatrician to speak with the patient before delivery; notification of the nursery is also important. Immediately after delivery, cultures of the placenta and baby are obtained, and the newborn is monitored carefully for signs and symptoms of infection.

Pharmacologic highlights

Medication or Drug ClassDosageDescriptionRationale
CefoxitinVaries by drug and patient conditionSecond-generation cephalosporinBroad-spectrum antibiotics are effective against gram-positive, gram-negative, aerobic, and anaerobic organisms; are less toxic; and cross the placenta to help the fetus
MezlocillinVaries by drug and patient conditionExtended-spectrum antibioticsBroad-spectrum antibiotics are effective against gram-positive, gram-negative, aerobic, and anaerobic organisms; are less toxic; and cross the placenta to help the fetus
Ticarcillin; piperacillinVaries by drug and patient conditionPenicillinBroad-spectrum antibiotics are effective against gram-positive, gram-negative, aerobic, and anaerobic organisms; are less toxic; and cross the placenta to help the fetus

Other Drugs: Other antibiotics such as clindamycin, gentamycin, ampicillin, and penicillin may also be used. Most often combinations of antibiotics are used to treat chorioamnionitis.


Anticipatory guidance provided by the nurse is beneficial for the patient. Provide information about antibiotic therapy, procedures that occur during labor and delivery, and possible outcomes for the infant. Because the patient’s anxiety level is elevated, you may need to repeat information several times. Allow the patient to express her fears. Answer the questions of the significant others and take time to listen to their concerns as well.

Monitor the patient for signs of infection after delivery, including the mother’s lochia, fundal height, vital signs, and incisional healing. The patient with an intrauterine infection is at a higher risk for a postpartum hemorrhage than are her noninfected counterparts. Careful and frequent assessments for vaginal bleeding and firmness of the fundus are critical. If the fundus is “boggy,” massage the fundus until firm.

Evidence-Based Practice and Health Policy

Nasef, N., Shabaan, A.E., Schurr, P., Iaboni, D., Choudhury, J., Church, P., & Dunn, M.S. (2013). Effect of clinical and histological chorioamnionitis on the outcome of preterm infants. American Journal of Perinatology, 30(1), 59–68.

  • Chorioamnionitis has significant implications for neonatal and maternal health and may have longer-term implications for child health.
  • In one retrospective study among a sample of 274 preterm infants with a mean gestational age of 27 weeks (SD, ± 1.6 weeks), 47% were born to mothers with clinical or histological chorioamnionitis. Eighty-four percent of all the infants survived to discharge home, and there were no differences in mortality rates between mothers with and without chorioamnionitis.
  • The presence of intraventricular hemorrhage was significantly higher among infants born to mothers with clinical (39%) and histological chorioamnionitis (27%) than mothers without chorioamnionitis (16%) (p < 0.05).
  • Among the 180 infants available for follow-up at 18 months, children born to mothers with clinical chorioamnionitis had lower cognitive (88 ± 10), language (82 ± 12), and motor scores (89 ± 11) compared to the children born to mothers without chorioamnionitis (99 ± 13, 92 ± 15, 97 ± 13, respectively) (p < 0.05).

Documentation guidelines

  • Maternal vital signs; fetal heart rate pattern; uterine activity; maternal response to antibiotics; color, odor, and consistency of vaginal discharge
    If the Patient is Delivered
  • Maternal and infant vital signs; amount and odor of lochia; involution of uterus; assessment of episiotomy or abdominal incision
  • Amount of the infant’s fluid intake and output, infant’s response to antibiotics, daily weight of the baby

Discharge and home healthcare guidelines

postpartum complications if the patient is undelivered.
Instruct the patient to inform the physician if her temperature rises above 100.4°F. Increased vaginal bleeding, foul odor of the vaginal discharge, increased uterine tenderness, difficulty urinating, the appearance of hardened red areas in the breasts, pain in the calves of the legs, incisional pain, and redness or drainage from the incision are also reasons to notify the physician.

infant complications.
Instruct the patient to inform the pediatrician if the baby’s rectal temperature is above 101°F. Decreased interest in feeding, increased jaundice, a red or draining umbilical cord or circumcision site, increased irritability, difficulty breathing, lack of a bowel movement in 2 days, and fewer than six wet diapers a day are also reasons to notify the pediatrician.

Instruct the patient to take the entire prescription of antibiotics even if symptoms subside. Encourage the patient to notify the physician if symptoms persist when the prescription has ended.

Instruct the patient to abstain from sexual intercourse until the 6-week follow-up visit. Teach the patient to resume activity gradually and to limit use of stairs for the first week. Explain that patients should not lift anything heavier than their infant for the first 2 weeks after delivery. Teach vaginally delivered patients to avoid driving for 1 week and cesarean patients to avoid driving until the pain ceases.

Diseases and Disorders, © 2011 Farlex and Partners
References in periodicals archive ?
After discharge, histopathologic examination of the placenta showed funiculitis and chorioamnionitis with clusters of nonflagellated parasites.
In this material, two-thirds of cases of perinatal mortality were associated with congenital anomalies or acute chorioamnionitis but did not feature histologic signs of placental hypoxia.
The role of proteomics in the diagnosis of chorioamnionitis and early-onset neonatal sepsis.
There were no cases of chorioamnionitis. Birth weight was similar (about 1,800 grams).
The absence of chorioamnionitis with present study maybe due to routine use of prophylactic antibiotic in all cases of premature rupture of membranes.
In group A, 8 (4.1%) patients developed chorioamnionitis and 13 (6.7%) patients in group B (p = 0.262).
Maternal outcome in 16 cases of Preterm Premature Rupture of Membrane findings revealed septicemia in 12% cases and Chorioamnionitis in 12% cases.
The guidelines from the CDC were revised so that healthy-appearing infants born to mothers who had inadequate intrapartum antibiotic prophylaxis for group B streptococcus would be evaluated for early-onset GBS sepsis only if they had additional indications: gestational age of less than 37 weeks, rupture of membranes that preceded delivery by 18 hours or longer, maternal fever, or chorioamnionitis. Preliminary studies indicated that implementing these more restrictive guidelines would decrease excessive evaluations of healthy newborns by approximately 25%, "but the real-life impact of changes in medical policy is rarely straightforward," the investigators said.
Her condition was so bad the 31-yearold dentist suffered multi-organ failure due to blood poisoning, a rare strain of E.coli and a miscarriage at 17 weeks with chorioamnionitis - an infection of foetal membranes.
The most significant maternal complication of PPROM is infection; intra-amniotic infection or chorioamnionitis is seen in 13-60% of pregnant women for example, and postpartum infection or endometritis is seen in 2-13%.
Results: Teenage mothers were more likely to suffer from severe anaemia (8% versus 4.3%; p = 0.03) and chorioamnionitis (2.8% vs 0.8%, p = 0.01) and their infants were more likely to suffer from post maturity (4.6% vs 1.8%, P = 0.02) and meconium aspiration syndrome (6.5% vs 2.4%, p less than 0.01) compared to non-teenage mothers.