Puerperal Infection (Endometritis)

Introduction

• Description: Although the term puerperal infection can be used to describe any infection during or after labor, it generally applies to the infection of the uterus and surrounding tissues after delivery. This can vary from mild to life-threatening severities. Some of the most severe infections may appear within hours of delivery and are often opportunistic and not associated with reliable risk factors. Vigilance and aggressive diagnosis and treatment are required.

• Prevalence: Estimated to occur in 1%–3% of vaginal deliveries; approximately 15% if chorioamnionitis is present during labor. Following cesarean delivery: 1.5%–10% if antibiotic prophylaxis is administered during delivery and 50%–90% without antibiotic prophylaxis in some series.

• Genetics: No genetic pattern.

Etiology and Pathogenesis

• Causes: Colonization and infection of the tissues of the uterus, peritoneum, or surrounding organs; typically, a polymicrobial infection (70%) that involves a mixture of two to three aerobes and anaerobes. The most common organisms are group B streptococci; other facultative streptococci; Gardnerella vaginalis; and Escherichia coli, Bacteroides, and Peptostreptococcus species. Infection by clostridia or group A streptococci may result in rapidly progressive soft-tissue (subcutaneous tissue, muscle, or myometrial) infection. Abscesses usually contain both aerobic and anaerobic bacteria such as Bacteroides species ( Bacteroides bivius, B. disiens, or B. fragilis ). Approximately 50% of ascending uterine infections involve Chlamydia trachomatis.

• Risk Factors: Cesarean delivery (10- to 30-fold increase over vaginal delivery), invasive procedures during labor, prolonged rupture of the membranes, prolonged labor, multiple vaginal examinations, retained placental fragments, manual removal of the placenta, urinary catheter, bacterial vaginosis, intravenous line(s), low socioeconomic or nutritional status, maternal age, anemia, and chronic disease (diabetes).

Signs and Symptoms

• Fever (90%; >38.5°C by 24 hours) and tachycardia (often developing rapidly after delivery)

• Uterine tenderness (may be absent)

• Purulent drainage from the uterus

• Signs of septic or cardiovascular shock (hypotension, anxiety, disorientation, prostration)

• Impaired renal function (<20 mL/hr urine production)

• Altered white blood count (<1000 or ≥25,000)

• Hemolysis or hemoconcentration

• Uterine subinvolution and excessive bleeding

• The United States Joint Commission on Maternal Welfare defines postpartum febrile morbidity as an oral temperature of ≥38.0°C (≥100.4°F) on any 2 of the first 10 days postpartum, exclusive of the first 24 hours.

Diagnostic Approach