Puerperal Infection (Postpartum Infection), Endometritis, Mastitis, Breast Abscess

Introduction

Puerperal infection, also known as postpartum infection, encompasses a spectrum of bacterial infections of the female reproductive tract following childbirth or miscarriage. These infections generally occur within the first 10 days postpartum and can become life-threatening if diagnosis and treatment are delayed. Prompt recognition, appropriate antibiotic therapy, and supportive measures are paramount in preventing severe sequelae.

---

Etiology and Risk Factors

Common Causes

1. Endometritis: Infection of the uterine lining (most common etiology).
2. Wound Infections: Can occur at cesarean section incisions, episiotomy sites, or perineal lacerations.
3. Mastitis: Breast infection often related to lactation.
4. Urinary Tract Infections (UTIs): Associated with catheterization or postpartum urinary retention.
5. Septic Thrombophlebitis: Infection leading to thrombosis in pelvic veins.

Risk Factors

• Cesarean Delivery, especially emergency procedures.
• Prolonged Rupture of Membranes (>18 hours).
• Prolonged Labor or frequent vaginal examinations.
• Retained Products of Conception.
• Manual Removal of Placenta.
• Poor Aseptic Technique during delivery.
• Anemia, malnutrition, or immunosuppression (e.g., diabetes, HIV).
• Pre-existing Vaginal Infections (e.g., bacterial vaginosis).
• Obesity, which can predispose to wound infections.

---

Pathophysiology

During or after delivery, the protective barriers of the uterus and cervix can be disrupted, allowing bacteria to ascend from the vagina. The postpartum uterine environment, rich in necrotic decidual tissue and lochia, promotes bacterial overgrowth. Organisms typically involved are polymicrobial, including both aerobic and anaerobic bacteria such as Streptococcus pyogenes, Staphylococcus aureus, Escherichia coli, Bacteroides fragilis, and occasionally Clostridium species.

---

Clinical Presentation

General Symptoms

• Fever ≥ 38°C (most commonly within the first 24 hours postpartum).
• Chills, rigors, malaise.
• Tachycardia (maternal heart rate >100 bpm).
• Anorexia.
• Pale or clammy skin in more severe cases.

Site-Specific Manifestations

1. Endometritis
   • Lower abdominal or pelvic pain.
   • Foul-smelling lochia (vaginal discharge).
   • Uterine tenderness on palpation.
2. Wound Infections (C-section or Episiotomy)
   • Erythema, warmth, and tenderness over the incision site.
   • Possible purulent or seropurulent discharge.
   • Localized pain and edema.
3. Mastitis/Breast Abscess
   • Localized breast pain, erythema, and warmth.
   • Fluctuant mass if abscess formation is present.
   • Often associated with breastfeeding difficulties.
4. Urinary Tract Infection
   • Dysuria, frequency, urgency.
   • Suprapubic discomfort or flank pain (if pyelonephritis).
5. Septic Pelvic Thrombophlebitis
   • Persistent fever is unresponsive to broad-spectrum antibiotics.
   • Lower abdominal or pelvic pain; is often a diagnosis of exclusion.

---

Physical Examination Findings

• Vital Signs: Fever, tachycardia, possible hypotension in severe cases (suggestive of sepsis).
• Abdominal Examination:
  • Lower abdominal tenderness, particularly over the uterus.
  • Uterine tenderness and possible subinvolution on palpation.
• Pelvic Examination:
  • Foul-smelling lochia.
  • Cervical motion tenderness (in severe endometritis).
  • Possible identification of retained products of conception if the cervix is open.
• Wound Inspection:
  • Redness, edema, tenderness, or purulent discharge at C-section or episiotomy sites.
• Breast Examination:
  • Localized erythema, warmth, and tenderness in mastitis.
  • Fluctuance on palpation if an abscess is present.

---

Diagnostic Workup

Clinical DiagnosisDiagnosis is often clinical, based on postpartum fever, uterine tenderness, and the characteristic features of the suspected infection (e.g., wound infection, mastitis, endometritis).

Laboratory Studies

• Complete Blood Count (CBC): Leukocytosis is common, although WBC counts can be elevated postpartum even without infection. A trend (rising WBC count) can be more meaningful than a single value.
• Blood Cultures: Indicated if there are signs of sepsis or severe infection.
• Urinalysis and Urine Culture: Rule out urinary tract infections.
• Wound Culture: If suspicion of wound infection.
• Endometrial Cultures: Not universally done; selective use in refractory cases or for guiding antibiotic therapy.

Imaging

• Pelvic Ultrasound: Useful to exclude retained products of conception, assess for pelvic abscess, or evaluate uterine subinvolution.
• CT Scan: May be indicated in cases of suspected pelvic abscess, deep pelvic collections, or septic pelvic thrombophlebitis when clinical improvement is not observed despite antibiotic therapy.

---

Differential Diagnosis

• Endometritis
• Mastitis/Breast Abscess
• Urinary Tract Infection
• Wound Infection
• Septic Pelvic Thrombophlebitis
• Retained Products of Conception
• Pelvic Abscess
• Pulmonary Embolism (if respiratory distress or chest symptoms)
• Deep Vein Thrombosis (if unilateral leg swelling)

---

Management

General Principles

1. Early Recognition and Intervention: Start treatment as soon as puerperal infection is suspected.
2. Broad-Spectrum Antibiotic Coverage: Must target both aerobic and anaerobic bacteria.
3. Address Underlying Factors: Remove or manage any retained products of conception, debride or drain abscesses, and optimize wound care.

Antibiotic Regimens

1. Endometritis / Postpartum Wound Infections
   • Clindamycin (900 mg IV every 8 hours) PLUS Gentamicin (1.5 mg/kg IV every 8 hours).
   • Add Ampicillin if coverage for Enterococcus is necessary or if a broader spectrum is required.
   • Treatment is typically continued until the patient is afebrile for at least 24–48 hours.
2. Mastitis / Breast Abscess
   • Dicloxacillin is 500 mg orally four times a day (if there is no MRSA risk).
   • Consider Clindamycin or Trimethoprim-Sulfamethoxazole if MRSA is suspected or in penicillin-allergic patients.
   • Encourage continued breastfeeding or pumping to prevent milk stasis.
   • Surgical drainage for established breast abscesses.
3. Septic Pelvic Thrombophlebitis
   • Broad-spectrum antibiotics are similar to endometritis regimens.
   • Addition of Heparin anticoagulation can be beneficial, as it may help resolve persistent fever and reduce clot extension.

Supportive Therapy

• Intravenous Fluids: Correct dehydration and maintain hemodynamic stability.
• Analgesics: NSAIDs or acetaminophen for pain and fever control.
• Monitoring: Watch for signs of clinical deterioration, including hemodynamic instability.

Surgical Interventions

• Drainage of Abscesses: Breast abscess, pelvic abscess, or infected wound collections.
• Evacuation of Retained Products: Dilation and curettage (D&C) if indicated.
• Debridement of Necrotic Tissue: For severe or necrotizing infections.

---

Complications

• Sepsis and Septic Shock
• Pelvic Abscess Formation
• Septic Pelvic Thrombophlebitis
• Chronic Pelvic Pain
• Infertility (if the infection involves the fallopian tubes or leads to scarring)
• Disseminated Intravascular Coagulation (DIC) in severe septic cases

---

Prognosis

With early and appropriate treatment, the majority of puerperal infections resolve without permanent sequelae. However, delayed recognition or inadequate management can lead to severe outcomes, including life-threatening sepsis.

---

Prevention

1. Aseptic Technique: Adherence to sterile procedures during labor and delivery.
2. Prophylactic Antibiotics: Recommended for cesarean sections (e.g., a single preoperative dose of Cefazolin).
3. Proper Breastfeeding Techniques: Reduces the risk of mastitis.
4. Prompt Treatment of Antepartum UTIs and Vaginal Infections: Minimizes bacterial load.
5. Optimizing Maternal Health: Correction of anemia, managing diabetes, and nutritional support during pregnancy.

---

Patient Education: When to Seek Medical Attention

• Postpartum fever ≥ 38°C
• Chills, rigors, or feeling faint
• Foul-smelling vaginal discharge
• Persistent lower abdominal or pelvic pain
• Wound redness, drainage, or separation of incision
• Breast redness, tenderness, or severe engorgement
• Signs of systemic illness (e.g., confusion, rapid breathing, severe weakness)

---

Conclusion

Puerperal (postpartum) infection is a significant cause of maternal morbidity and, if untreated, can rapidly progress to life-threatening complications such as sepsis and septic shock. A high index of suspicion, early diagnostic steps, and aggressive management with broad-spectrum antibiotics remain the cornerstones of care. Preventive strategies—including the use of prophylactic antibiotics, proper breastfeeding techniques, and meticulous aseptic protocols—are essential to reduce incidence. With timely intervention, most patients recover fully and avoid long-term consequences.