Postpartum (puerperal) infection is any bacterial infection of the genital tract or related sites after birth. It remains a major cause of maternal sepsis and death worldwide. A classic definition of puerperal febrile morbidity is a temperature of 38.0 °C (100.4 °F) or higher on any 2 of the first 10 days after birth, excluding the first 24 hours; in practice, any fever of 38.0 °C or higher needs evaluation, and a very high fever in the first 24 hours can signal group A streptococcal infection.

Why postpartum clients are vulnerable: the placental site is a large open wound; lochia is a culture medium; the genital tract is traumatized; the cervix is open; instrumentation, catheters, and incisions provide entry points; blood loss and anemia lower resistance.

Main types

Risk factors

• Cesarean birth (the single most important risk factor for endometritis)
• Prolonged rupture of membranes and prolonged labor, many vaginal examinations, intraamniotic infection
• Internal fetal monitoring, manual removal of the placenta, retained placental fragments
• Postpartum hemorrhage, anemia, obesity, diabetes, GBS colonization, poor hygiene
• UTI: urinary catheterization, retention, birth trauma to the bladder, epidural
• Mastitis: milk stasis from infrequent or ineffective feeding, nipple damage, oversupply, abrupt weaning

• Vital signs: fever, tachycardia (often the first sign of sepsis), tachypnea, hypotension (late)
• Uterus: tenderness, boggy or poorly involuted fundus; lochia: foul odor, purulent, or increased
• Incision/perineum (REEDA): redness, edema, ecchymosis, discharge, poor approximation
• Breasts: localized firmness, redness, warmth, tenderness; fluctuant mass suggests abscess
• Urinary symptoms, costovertebral angle tenderness
• Legs: calf or thigh pain, swelling (thrombophlebitis/DVT)
• General: chills, malaise, pain out of proportion, altered mental status

Breast conditions compared

Maternal sepsis warning signs: temperature ≥ 38.0 °C or < 36.0 °C, heart rate > 110/min, respiratory rate > 24/min, SBP < 90 mmHg, SpO2 < 95%, new confusion, oliguria (example thresholds; tools differ — use the facility's obstetric early warning tool) — many facilities use obstetric early warning systems to trigger a bedside evaluation.

• CBC (interpret WBC carefully — it is normally elevated for several days), blood cultures before antibiotics when sepsis is suspected, lactate
• Urinalysis and urine culture
• Wound culture; breast milk culture for severe, recurrent, or hospital-acquired mastitis or no response to antibiotics (MRSA)
• Pelvic ultrasound for retained tissue or abscess; breast ultrasound for abscess; CT for pelvic abscess or thrombophlebitis

Endometritis

• IV clindamycin plus gentamicin (gentamicin once daily is common) until the client is afebrile and improved for 24–48 hours; oral antibiotics afterward are usually unnecessary. Ampicillin is added if no improvement or GBS is suspected
• Look for retained tissue if the client does not improve
• Clindamycin: diarrhea and Clostridioides difficile colitis — report watery stools. Gentamicin: nephrotoxicity and ototoxicity — monitor creatinine, urine output, hearing, and levels as ordered
• Breastfeeding can usually continue

Prevention at cesarean: cefazolin within 60 minutes before incision (weight-adjusted), with azithromycin added for clients in labor or with ruptured membranes; vaginal cleansing before cesarean in labor.

Wound infection: open and drain, packing or negative-pressure therapy, antibiotics for cellulitis; necrotizing fasciitis needs urgent surgical debridement.

UTI: antibiotics based on culture (e.g., cephalexin); pyelonephritis needs IV therapy. Encourage fluids and frequent voiding. Nitrofurantoin is usually avoided while breastfeeding an infant younger than about 1 month or with infant G6PD deficiency (hemolysis risk).

Antibiotic safety reminders

• Ask about penicillin and cephalosporin allergy before the first dose; observe for rash, wheezing, or anaphylaxis
• Most of these antibiotics pass into milk in small amounts; watch the breastfed infant for loose stools, diaper rash, or thrush
• Vancomycin (for MRSA): infuse slowly to avoid flushing reaction; monitor kidney function and trough or AUC levels as ordered

Mastitis — current Academy of Breastfeeding Medicine approach (Protocol #36, 2022)

• Continue breastfeeding from the affected breast; milk is safe for the healthy term infant
• Feed the infant on demand; avoid overpumping and "emptying" the breast beyond the infant's needs (it drives oversupply)
• Ice packs and NSAIDs (ibuprofen) for inflammation and pain; supportive bra
• Avoid deep, forceful massage; gentle lymphatic drainage strokes only
• Antibiotics (e.g., dicloxacillin or cephalexin; clindamycin for penicillin allergy; cover MRSA if suspected) if symptoms do not improve within 12–24 hours or the client is systemically ill
• Abscess: ultrasound-guided needle aspiration or drainage; breastfeeding can usually continue on the affected side unless the drainage site interferes

This replaces older advice to apply heat and vigorously massage the lump.

Septic pelvic thrombophlebitis: anticoagulation (heparin) along with antibiotics.

Sepsis: early recognition, cultures, broad-spectrum antibiotics within 1 hour, fluid resuscitation, source control, escalation to critical care.

Listed in priority order.

1. Recognize sepsis early — trend vital signs, especially heart rate and respiratory rate; mental status; urine output; use the early warning tool and escalate
2. Give antibiotics on time — obtain cultures first (without delaying antibiotics); maintain serum levels by precise timing; watch for adverse effects
3. Fluid and comfort — IV and oral fluids, antipyretics, rest
4. Position — semi-Fowler's promotes drainage of lochia
5. Infection control and hygiene — hand hygiene; perineal care front to back; change pads at least every 4–6 hours and after voiding; wound care with aseptic technique
6. Bladder — prevent retention; remove catheters early
7. Breast care in mastitis — continue feeding, check latch, ice between feedings, analgesia
8. Support mother–infant contact — isolation is not required for most infections; breastfeeding continues

• Take temperature if feeling unwell; report 38.0 °C (100.4 °F) or higher, chills, foul lochia, increasing abdominal pain, wound redness or drainage, painful urination, or a red painful breast area
• Hand hygiene before and after perineal care and diaper changes; wipe front to back
• Change pads frequently; use showers; avoid tampons and douching until cleared
• Complete the full antibiotic course
• Mastitis: keep feeding, avoid tight bras, rest, fluids; seek care if not better in 24 hours or if a lump persists

• Fever ≥ 38.0 °C (100.4 °F) after the first 24 hours → evaluate for infection
• Endometritis: fever, uterine tenderness, foul lochia; biggest risk factor cesarean
• Treatment: clindamycin + gentamicin IV until afebrile 24–48 hours
• Tachycardia is an early sign of sepsis; antibiotics within 1 hour
• Wipe front to back; change pads at least every 4–6 hours
• Mastitis: continue breastfeeding, ice, NSAIDs, avoid deep massage and overpumping (ABM 2022)
• Mastitis organism: Staphylococcus aureus
• Persistent fever despite antibiotics → septic pelvic thrombophlebitis or abscess
• Cesarean prophylaxis: cefazolin within 60 minutes, add azithromycin in labor