Postpartum fever

Postpartum fever is a maternal temperature of 38.0°C or more occurring after the birth of the baby. It is most often defined as 38.0°C or more on two occasions at least 6 hours apart during the first 10 days after birth (excluding the first 24 hours), or a single reading of 38.5°C or more at any time.

The main clinical points:

• Treat every febrile postpartum woman as having possible sepsis until a source is found.
• Look first at the uterus (endometritis), the wound (caesarean, perineal), the urinary tract, the breasts and the chest.
• Remember group A streptococcus as a cause of rapid deterioration.
• Give broad spectrum antibiotics within the first hour for sepsis.
• Exclude venous thrombosis and non infectious causes when fever persists despite treatment.

Clinical relevance. Puerperal sepsis is a leading cause of maternal death worldwide and a frequent cause of readmission after discharge. Group A streptococcal infection can kill within 24 hours. Delay in recognising sepsis because the symptoms are attributed to the usual postpartum changes is a recurring cause of avoidable death.

Physiology. A low grade rise to 37.5 to 38.0°C in the first 24 hours is common (dehydration, exertion, epidural related fever). Milk coming in on days 3 to 5 may raise temperature to 38.4°C for under 24 hours.

The white cell count is raised in the first week (up to 20 to 25 x 10^9/L), and C reactive protein rises after caesarean section, so single values are unreliable. The uterus is a large wound with raw placental site and a lochia that offers a medium for bacteria.

Mechanisms. Ascending or contaminating bacteria invade the placental site, lacerations or surgical wounds, the urinary tract (catheter), the breasts (nipple damage), or the lungs (anaesthesia, immobility). The organisms are Escherichia coli, group A and B streptococci, Staphylococcus aureus, Bacteroides, anaerobic cocci, Klebsiella, Clostridium. Infection spreads through the myometrium, parametrium, pelvic veins and bloodstream.

Risk rises with:

• Prolonged rupture of membranes, long labour, multiple vaginal examinations.
• Instrumental birth, manual removal of the placenta, caesarean section (especially in labour).
• Obesity, diabetes, anaemia, retained products.
• Group B streptococcus colonisation and lower socioeconomic status.

Classification.

• By time: early (within 24 to 48 hours; often non infectious or chorioamnionitis continuing) and late (day 3 to 6 weeks).
• By source: genital tract (endometritis, parametritis, pelvic abscess, septic pelvic thrombophlebitis, retained products), wound (perineal, caesarean, episiotomy), urinary, breast, respiratory, vascular (intravenous cannula, thrombosis), central nervous system (post dural puncture meningitis, epidural abscess), and non infectious.
• By severity: fever, sepsis, severe sepsis, septic shock.

Key distinctions.

• Fever with a tender, soft uterus and foul lochia is endometritis.
• Fever with severe pain out of proportion to findings, rapid spread of redness or discoloured skin is necrotising infection.
• Fever with a rash, diarrhoea, hypotension and sore throat contacts suggests toxic shock.
• Unilateral breast redness and pain with fever is mastitis.
• Calf swelling suggests deep vein thrombosis.
• Persistent fever despite antibiotics suggests abscess, resistant organism, septic thrombophlebitis, or drug fever.

History

• Birth: date and mode of delivery, duration of rupture of membranes, duration of labour, number of vaginal examinations, chorioamnionitis, instrumental delivery.
• Also caesarean section (planned or in labour), manual removal of placenta, perineal tear or episiotomy, postpartum haemorrhage, antibiotic prophylaxis, epidural or spinal anaesthesia.
• Fever: onset, pattern, rigors, response to paracetamol.
• Symptoms: lower abdominal pain, foul or heavy lochia, wound pain, discharge or separation, perineal pain, dysuria, frequency, loin pain, breast pain, redness or hard areas.
• Also cough, sputum, pleuritic chest pain, breathlessness, calf pain or swelling, headache, neck stiffness, back pain, sore throat, rash, diarrhoea, vomiting.
• Contacts: household members with sore throat or skin infection (group A streptococcus), tuberculosis, COVID-19, influenza, chickenpox.
• Risk factors: diabetes, obesity (body mass index over 30), anaemia, HIV, immunosuppression, group B streptococcus carriage, previous infection, sickle cell disease, recent travel.
• Drugs: antibiotics, analgesics (NSAIDs mask fever), antipsychotics, antiepileptics.
• Infant: feeding, jaundice, fever, lethargy, signs of infection.
• Social: support at home, ability to return quickly, hygiene.

Examination

• Temperature, pulse, blood pressure, respiratory rate, saturation, capillary refill, mental state, urine output, hydration. Sepsis can be present with a normal temperature.
• Abdomen: uterine size (subinvolution), tenderness, tone, guarding, bowel sounds, distension, caesarean wound (erythema, induration, discharge, separation, crepitus).
• Perineum and vagina: stitches, swelling, discharge, haematoma, pus, dehiscence; speculum examination with swabs; lochia smell and amount; cervical os.
• Breasts: redness, heat, hardness, lumps, nipple damage, fluctuant area, axillary nodes.
• Chest: crackles, bronchial breathing, effusion.
• Legs: calf tenderness, swelling, asymmetry, leg length; iliac fossa or flank tenderness.
• Skin and throat: rash, erythema, blisters, discolouration, necrosis; tonsils, pharynx.
• Neurology: neck stiffness, photophobia, back tenderness at the epidural site, motor and sensory signs.
• Intravenous cannula and catheter sites.
• Bedside tests: urine dipstick, capillary glucose, lactate if septic.

Red flags

• Heart rate over 100 beats/min, respiratory rate over 20 breaths/min, systolic pressure under 100 mmHg, temperature under 36.0°C or over 38.0°C, new confusion, or oliguria.
• Severe pain out of proportion, rapidly spreading erythema, blisters, dusky or numb skin (necrotising infection).
• Sore throat, rash, diarrhoea and hypotension (toxic shock); contact with group A streptococcal disease.
• Uterine tenderness with foul lochia and tachycardia (endometritis with sepsis).
• Wound breakdown, spreading cellulitis, crepitus.
• Calf swelling, pleuritic pain, breathlessness (venous thromboembolism).
• Neck stiffness, severe headache, back pain, leg weakness, or urinary retention (meningitis, epidural abscess).
• Persistent fever after 48 hours of antibiotics, or fever with a rising white cell count.
• Fever with jaundice, vomiting and abdominal distension (pelvic abscess, ileus, hepatic abscess).
• Travel to a malaria area, HIV, or immunosuppression.
• Infant unwell (fever, poor feeding, lethargy).

Special groups.

• Women after caesarean section in labour have the highest risk of endometritis and wound infection.
• Women with diabetes and obesity have slower healing and higher wound infection rates.
• Women with HIV need earlier cultures and consideration of opportunistic infection.
• Breastfeeding women need drugs that are compatible with lactation, and breastfeeding is encouraged to continue.
• Region specific: unsafe home birth practices, retained products, unclean instruments and late presentation produce severe puerperal sepsis.

Organised by source. Each cause is common unless marked serious or uncommon.

Genital tract

• Endometritis (endomyometritis), the commonest cause, particularly after caesarean section.
• Retained placental tissue or membranes with infection.
• Serious: group A streptococcal sepsis and toxic shock syndrome.
• Serious: necrotising myometritis and uterine necrosis.
• Pelvic abscess, parametrial phlegmon, infected pelvic haematoma, tubo ovarian abscess.
• Serious: septic pelvic thrombophlebitis and ovarian vein thrombosis.
• Perineal tear or episiotomy infection and dehiscence.
• Vaginal or vulval haematoma that has become infected.
• Retained swab, tampon or foreign body.
• Gonococcal and chlamydial infection, Clostridium infection (gas gangrene).

Wound

• Caesarean wound infection (superficial, deep, organ space).
• Serious: necrotising fasciitis (abdominal wall or perineum).
• Wound haematoma and seroma.
• Intravenous cannula site infection and thrombophlebitis.

Urinary

• Cystitis, pyelonephritis (catheter, retention).
• Renal abscess, infected ureteric injury or urinoma after caesarean section.

Breast

• Lactational mastitis and breast abscess.
• Engorgement with milk fever.

Respiratory

• Pneumonia (aspiration after general anaesthesia, hospital acquired), atelectasis.
• Influenza, COVID-19, tuberculosis.
• Pulmonary embolism with infarction.

Vascular and thrombotic

• Deep vein thrombosis, pulmonary embolism, superficial thrombophlebitis.
• Infected vascular access, endocarditis (rare).

Central nervous system

• Serious: meningitis (post dural puncture, Streptococcus, Listeria).
• Serious: epidural or spinal abscess and haematoma.
• Cerebral venous thrombosis.

Gastrointestinal and hepatic

• Gastroenteritis, Clostridioides difficile infection after antibiotics.
• Ileus and bowel injury or perforation after caesarean section, intra abdominal abscess.
• Appendicitis, cholecystitis, pancreatitis.
• Viral hepatitis, hepatic infarct or haematoma (HELLP syndrome).

Systemic and non infectious

• Malaria, typhoid, dengue and other tropical infections.
• Drug fever (beta lactams, antiepileptics), transfusion reaction, serum sickness.
• Thyroid storm and postpartum thyroiditis.
• Pre eclampsia and postpartum cardiomyopathy.
• Autoimmune disease flare (systemic lupus erythematosus), vasculitis, haemolytic uraemic syndrome, thrombotic thrombocytopenic purpura.
• Peripartum cardiomyopathy and myocarditis.
• Dehydration, epidural related fever, oxytocin related water intoxication.
• Lymphoma and other malignancy (rare).

Stepwise reasoning

1. Measure temperature, heart rate, blood pressure, respiratory rate and mental state. Decide whether sepsis is present and start the first hour actions if so.
2. Take a history focused on the delivery, symptoms by system, contacts and infant.
3. Examine the uterus, wound, perineum, breasts, chest, legs, urinary tract and throat.
4. Send cultures and first line tests, then start broad spectrum antibiotics without waiting.
5. Choose imaging by the likely source and review the response at 48 hours.

First line tests

• Full blood count with differential (platelets), C reactive protein (trend), lactate, urea, creatinine, electrolytes, liver function tests, glucose, group and screen.
• Blood cultures (two sets, before antibiotics).
• Midstream or catheter urine for dipstick and culture.
• High vaginal and endocervical swabs for culture and nucleic acid amplification tests; swabs from wounds or perineum.
• Throat swab if sore throat or contact (group A streptococcus); breast milk culture if mastitis is recurrent or severe.
• Coagulation screen, fibrinogen if septic.
• Chest radiograph if respiratory signs.
• Malaria test if exposure.

Targeted tests

• Pelvic ultrasound: retained products (thickened endometrium with echogenic material and flow), uterine collection, wound haematoma, pelvic abscess, free fluid. Endometrial thickness alone is a poor guide.
• CT of the abdomen and pelvis with intravenous contrast (or MRI) for suspected abscess, ovarian vein or pelvic vein thrombosis, bowel injury, or fever unresponsive to antibiotics at 48 to 72 hours.
• Doppler ultrasound of the legs for deep vein thrombosis; CT pulmonary angiography or ventilation perfusion scan for suspected pulmonary embolism.
• MRI of the spine (urgent) for suspected epidural abscess or haematoma; lumbar puncture after imaging for suspected meningitis.
• Breast ultrasound for suspected abscess or persistent lump.
• Stool for Clostridioides difficile toxin when diarrhoea follows antibiotics.
• Echocardiography and repeat cultures if endocarditis is suspected.
• Thyroid function tests, haemolysis screen and renal function if no source is found.
• HIV test and tuberculosis testing (sputum Xpert MTB/RIF) in endemic regions.

Limitations. White cell count and C reactive protein are raised after delivery and operation. Culture from the genital tract has a high contamination rate; blood cultures are more reliable. Ultrasound cannot reliably distinguish retained products from normal lochia and clot.

Fever may be absent in severe sepsis (particularly with NSAIDs). No cause is found in a minority of women, and then the course of treatment response guides diagnosis.

Immediate steps. If sepsis is possible, within 1 hour:

• Oxygen to keep saturation at 94% or more.
• Intravenous access, blood cultures, lactate, broad spectrum intravenous antibiotics.
• Crystalloid 500 mL boluses (up to 30 mL/kg for hypotension or lactate of 4 mmol/L or more, with reassessment after each bolus).
• Start noradrenaline through a large vein if mean arterial pressure stays under 65 mmHg after fluids.
• Call the senior obstetrician, anaesthetist and microbiologist.
• Isolate the woman for 24 hours of effective treatment if group A streptococcus is suspected, with droplet and contact precautions.
• Check the baby.

Supportive care.

• Paracetamol 1 g orally or intravenously every 4 to 6 hours (maximum 4 g daily; 3 g daily with alcohol use, malnutrition or liver impairment).
• Ibuprofen 400 mg orally every 6 to 8 hours with food may be added in women with no renal impairment, ulcer or bleeding (maximum 1.2 g daily without supervision, up to 2.4 g daily for a short course). Avoid it in sepsis with hypotension, haemorrhage or renal impairment.
• Intravenous or oral fluids.
• Thromboprophylaxis with enoxaparin 40 mg subcutaneously once daily (20 mg under 50 kg; 60 mg for 91 to 130 kg; reduce for creatinine clearance under 30 mL/min) in all admitted febrile women with additional risk factors, for up to 6 weeks.

Empirical antibiotics for sepsis from the genital tract (before cultures)

• Piperacillin with tazobactam 4.5 g intravenously every 6 hours; or meropenem 1 g intravenously every 8 hours when severe or after recent hospital care.
• Add clindamycin 900 mg intravenously every 8 hours when toxic shock or group A streptococcal infection is possible.
• Or clindamycin 900 mg intravenously every 8 hours with gentamicin 5 mg/kg intravenously once daily (adjusted to renal function) for endometritis. Add ampicillin 2 g intravenously every 6 hours if there is no improvement at 48 hours (enterococcal cover).
• Or ceftriaxone 2 g intravenously once daily with metronidazole 500 mg intravenously every 8 hours.
• Add vancomycin 25 mg/kg loading dose then 15 mg/kg every 12 hours (adjusted to levels) when methicillin resistant Staphylococcus aureus is possible.
• Continue until the woman has been afebrile for 24 to 48 hours. No oral course is needed after endometritis with a good response. Narrow to culture results; review at 48 hours.

Endometritis. Clindamycin 900 mg intravenously every 8 hours with gentamicin 5 mg/kg intravenously once daily. If no response in 48 hours, add ampicillin 2 g every 6 hours, look for retained products, abscess or pelvic vein thrombosis, and consider imaging.

Oral step down for mild disease: co-amoxiclav 625 mg orally every 8 hours for 5 to 7 days, or amoxicillin 500 mg every 8 hours with metronidazole 400 mg every 8 hours. Evacuate retained products under antibiotic cover. Compatible with breastfeeding.

Group A streptococcal sepsis and toxic shock.

• Benzylpenicillin 2.4 g (4 million units) intravenously every 4 hours with clindamycin 900 mg intravenously every 8 hours (for toxin suppression).
• Add a second agent such as meropenem or gentamicin until cultures are known.
• Consider immunoglobulin 1 g/kg intravenously on day 1, then 0.5 g/kg on days 2 and 3, in toxic shock.
• Urgent source control (debridement, drainage, hysterectomy for uterine necrosis); high dependency or intensive care.
• Notify the public health team; give antibiotic prophylaxis to close contacts as directed; isolate the baby's care appropriately and assess the baby.

Wound infection

• Superficial cellulitis: flucloxacillin 500 mg to 1 g orally every 6 hours for 5 to 7 days; clindamycin 450 mg orally every 8 hours for penicillin allergy; intravenous flucloxacillin 1 to 2 g every 6 hours for severe infection.
• Abscess or collection: drainage is the primary treatment. Open the wound, drain, and culture; pack or dress. Antibiotics for spreading cellulitis or systemic illness.
• Suspected methicillin resistant Staphylococcus aureus: doxycycline 100 mg orally twice daily for 7 days (acceptable in short courses while breastfeeding) or vancomycin intravenously.
• Perineal infection or dehiscence: co-amoxiclav 625 mg orally every 8 hours for 5 days (or cefalexin 500 mg every 6 hours with metronidazole 400 mg every 8 hours).
• Also analgesia, sitz baths, wound care, and secondary repair after 3 months or earlier once clean (early repair after 6 to 8 weeks in selected women).
• Necrotising fasciitis: surgical emergency. Broad spectrum antibiotics (benzylpenicillin, clindamycin and a carbapenem or gentamicin) and repeated debridement.

Urinary infection. Cystitis: cefalexin 500 mg orally every 12 hours for 5 to 7 days. Pyelonephritis: ceftriaxone 1 to 2 g intravenously once daily until afebrile for 24 to 48 hours, then oral cefalexin 500 mg every 6 hours to complete 10 to 14 days. Look for retention or obstruction. Nitrofurantoin 100 mg modified release twice daily is acceptable in breastfeeding women with a healthy term infant.

Mastitis and breast abscess. Flucloxacillin 500 mg to 1 g orally every 6 hours for 10 to 14 days (cefalexin 500 mg every 6 hours or clindamycin 300 to 450 mg every 8 hours for penicillin allergy). Continue emptying the breast by feeding or expression. Aspiration or drainage of an abscess under ultrasound. Continue breastfeeding where possible.

Pneumonia. Amoxicillin 1 g orally three times daily with azithromycin 500 mg orally daily for 3 days (or ceftriaxone 2 g intravenously with azithromycin 500 mg intravenously for severe illness) for 5 to 7 days. Oxygen, chest physiotherapy. Influenza is treated with oseltamivir 75 mg orally twice daily for 5 days.

Septic pelvic thrombophlebitis and ovarian vein thrombosis. Therapeutic enoxaparin 1 mg/kg subcutaneously every 12 hours (once daily for creatinine clearance under 30 mL/min) or unfractionated heparin infusion, with broad spectrum antibiotics. Give 7 days of antibiotics and at least 6 weeks to 3 months of anticoagulation (longer if extensive). It is a diagnosis of exclusion when fever persists with a normal pelvis. Warfarin is compatible with breastfeeding.

Pelvic abscess. Percutaneous drainage under imaging, or laparotomy, with antibiotics. Continue until afebrile and collection resolved.

Meningitis and epidural abscess. Ceftriaxone 2 g intravenously every 12 hours with vancomycin 15 to 20 mg/kg intravenously every 8 to 12 hours (and dexamethasone 10 mg intravenously every 6 hours for 4 days for suspected bacterial meningitis). Neurosurgical review for epidural abscess; urgent decompression for neurological deficit.

Deep vein thrombosis and pulmonary embolism. Therapeutic enoxaparin 1 mg/kg every 12 hours, followed by warfarin (target international normalised ratio 2.0 to 3.0) overlapping for at least 5 days, or a direct oral anticoagulant in women who are not breastfeeding, for at least 3 months in total.

Clostridioides difficile. Vancomycin 125 mg orally four times daily for 10 days; stop unnecessary antibiotics.

Engorgement and milk fever. Frequent feeding or expression, cold compresses between feeds, ibuprofen 400 mg orally every 6 to 8 hours, and reassurance. Fever resolves within 24 hours.

Drug fever and non infectious causes. Stop the suspected drug; treat the underlying disease (thyroid storm, lupus); review at 48 to 72 hours.

Retained products. Evacuation under antibiotic cover (cefazolin 2 g intravenously once with metronidazole 500 mg intravenously) after antibiotics have been started. Misoprostol 800 microgram sublingually for selected small retained products. Send tissue for histology.

Baby and breastfeeding. Assess the baby for infection (temperature, feeding, jaundice, tone, respiratory rate) and notify the neonatal team for group A streptococcus, chorioamnionitis, or maternal sepsis. Continue breastfeeding unless the woman is too unwell or a drug is contraindicated. Give glucose and monitor if the baby is unwell.

Special groups.

• Obesity: use weight based dosing and longer antibiotic prophylaxis.
• Diabetes: monitor glucose and adjust insulin.
• HIV: continue antiretroviral therapy, and consider opportunistic infection.
• Renal impairment: adjust gentamicin and avoid nephrotoxic drugs.
• Region specific: when referral is delayed, give the first dose of ceftriaxone 2 g intravenously or intramuscularly with metronidazole at the first facility and transfer with an escort.

Monitoring. Observations every 15 minutes to 1 hour in sepsis, then every 4 hours. Temperature, pulse, blood pressure, respiratory rate, saturation and mental state with a track and trigger chart. Strict fluid balance. Lactate repeated within 2 hours. Daily bloods (full blood count, creatinine, liver tests, C reactive protein). Repeat cultures. Wound and uterine reviews daily. Gentamicin levels if more than 3 doses or renal impairment.

Referral and escalation. Refer to critical care for septic shock, lactate over 4 mmol/L, respiratory failure, or organ dysfunction. Involve microbiology early. Refer to the gynaecology or general surgery team for abscess, necrotising infection, bowel injury or hysterectomy. Refer to haematology for thrombosis in unusual sites. Notify public health for group A streptococcal disease.

Admission criteria. Temperature of 38.0°C or more with any red flag, tachycardia, uterine tenderness, foul lochia, wound infection with systemic features, pyelonephritis, suspected group A streptococcal infection, pneumonia needing oxygen, inability to take oral medication, or no reliable follow up.

Women with a mild breast, wound or urinary infection, normal observations and a reliable home may be treated as outpatients with review within 24 to 48 hours.

Discharge and follow up. Discharge when afebrile for 24 to 48 hours, observations are normal, oral treatment (if needed) is tolerated and the source is identified. Complete antibiotic courses, review wound and perineum at 1 week, and arrange a postnatal review at 6 weeks. Advise on hand hygiene, wound care and breastfeeding. Check for post sepsis symptoms and provide psychological support.

Safety netting. Return at once for fever or shivering, fast heartbeat or breathing, foul discharge, increasing abdominal or wound pain, redness spreading, a hard or red breast, calf pain or swelling, chest pain, breathlessness, headache with neck stiffness, rash, or the baby being unwell.