Sepsis in pregnancy and postpartum

Sepsis in pregnancy and the postpartum period is characterized by life-threatening organ dysfunction caused by a dysregulated immune response to infection. It can be due to obstetric-related causes (e.g., intra-amniotic infection, septic abortion) or nonobstetric causes (e.g., urinary tract infection, pneumonia). Clinical features are similar to those in nonpregnant or postpartum individuals, but some normal physiological changes in pregnancy can mask early signs. Diagnosis and management are similar to those for sepsis in nonpregnant individuals; when sepsis is suspected, early fluid resuscitation, empiric antibiotics, and referral to a specialist (e.g., maternal fetal-medicine, intensive care) is recommended to reduce morbidity and mortality.

• Maternal sepsis: organ dysfunction caused by a dysregulated immune response to infection that occurs during pregnancy, childbirth, or up to 42 days after the end of pregnancy (i.e., delivery, abortion, or pregnancy loss) ^[1][2]
• Postpartum sepsis: maternal sepsis that develops between birth and 6 weeks postpartum ^[3]

• Incidence: ∼ 0.06 % of pregnancies ^[4]
• Sepsis is the second most common cause of maternal mortality in the US. ^[2][5][6]

Sepsis during pregnancy occurs approx. 2–2.5 times more frequently in Black, Asian, Pacific Islander, and Native American patients than in White patients due to social determinants of health, including systemic racism. ^[4][6]

Epidemiological data refers to the US, unless otherwise specified.

Common sources ^[2][6]

• Obstetric
  • Septic abortion
  • Intra-amniotic infection
  • Postpartum endometritis
  • Soft-tissue infection or wound infection (e.g., from cesarean delivery, perineal wound, mastitis)
• Nonobstetric
  • Urinary tract infection (UTI) and pyelonephritis ^[6]
  • Pneumonia
  • Gastrointestinal causes (e.g., appendicitis, cholangitis)
  • See also “Etiology of bloodstream infections.”

Pathogens

• Common bacterial pathogens (infection is often polymicrobial) ^[2]
  • Often polymicrobial
  • Escherichia coli
  • Streptococci spp. (e.g., group A streptococcus)
  • Staphylococcus aureus (MRSA)
  • S. epidermidis
  • Klebsiella pneumoniae
  • Proteus
  • Haemophilus influenza
  • Listeria monocytogenes
• Viral and fungal pathogens ^[2]
  • Influenza
  • Varicella zoster
  • Herpes simplex virus
  • COVID-19
  • Candida spp. (rare but high mortality)

Risk factors for sepsis in pregnancy and postpartum ^[3][6][7]

• Chronic conditions (e.g., diabetes mellitus, chronic hypertension, obesity, chronic kidney disease, congestive heart failure) ^[8]
• Cesarean delivery
• Retained products of conception ^[2]
• Prolonged rupture of membranes
• Invasive procedures (e.g., amniocentesis, cerclage, uterine instrumentation) ^[2]
• Trauma (e.g., obstetric lacerations)
• Prolonged uterine bleeding ^[2]
• Multifetal gestation
• Nulliparity
• Adverse social determinants of health ^[8]

Immunological down regulation that occurs during pregnancy and persists into the postpartum period increases the risk for sepsis. ^[2]

• Clinical features of sepsis in nonpregnant individuals are similar to those in pregnant and postpartum individuals.
• Early symptoms are often nonspecific and insidious.
• Physiological changes during pregnancy and the postpartum period (e.g., increased cardiac output, vasodilation) can mask vital sign changes due to infection. ^[2]
• Features consistent with underlying infection may also be present, e.g.:
  • Clinical features of UTI
  • Clinical features of pneumonia
  • Clinical features of intra-amniotic infection
  • Clinical features of mastitis
  • Clinical features of postpartum endometritis
  • Clinical features of septic abortion

Consider sepsis in pregnant or postpartum people with unexplained vital sign abnormalities, even if they are afebrile. ^[6]

Diagnostic studies are usually performed at the same time as initial stabilization and management.

• Perform a comprehensive physical examination, including a pelvic examination. ^[2]
• Obtain general diagnostic studies for sepsis (e.g., CBC, lactate, blood cultures); tailor further studies based on the suspected underlying source. ^[6]
• Additional laboratory studies for maternal sepsis include:
  • Additional cultures (e.g., cervical, uterine, wound) depending on the suspected source ^[2]
  • Diagnostics of genitourinary chlamydia and diagnostics for gonorrhea in patients with pelvic infections ^[2]
• Additional imaging for maternal sepsis may include: ^[2][6]
  • Suspected retained products of conception: pelvic ultrasound ^[2]
  • Pyelonephritis in pregnancy: renal ultrasound or MRI ^[9]
  • Abscess and/or deep pelvic infection
    • During pregnancy: MRI or ultrasound ^[10]
    • Postpartum or postabortion: CT abdomen and pelvis preferred ^[2]

Do not delay empiric antibiotic therapy while awaiting laboratory results.

Interpret lactate levels with caution during labor, as elevations can reflect normal physiological responses rather than pathology. ^[6]

Management of sepsis is similar in pregnant and postpartum individuals and nonpregnant individuals.

Initial management

• Sepsis screening tools (e.g., quick SOFA score) have not been validated for use in obstetrics. ^[2][6]
• Start management of maternal sepsis if new-onset organ dysfunction or ≥ 2 of the following occur: ^[6]
  • Temperature: ≥ 38.0°C
  • Heart rate: > 110/minute
  • Respiratory rate: > 24/minute
  • WBCs: > 15,000/mm³or < 4,000/mm³ or > 10% bands
• Initiate fluid resuscitation with balanced crystalloid fluid.
  • No signs of shock: 1–2 L over 3 hours ^[2][6]
  • Signs of shock (e.g., mean arterial pressure < 65 mm Hg): Manage as maternal septic shock. ^[6]
• Start empiric antibiotics. ^[6]
  • Use source-directed antibiotics if a focus is suspected.
  • Use empiric antibiotics for maternal sepsis with coverage for obstetric causes if the source is unknown.
• Consult specialists as needed.
  • Infectious diseases: to tailor antibiotic choices ^[6]
  • Obstetrics and/or maternal-fetal medicine: for obstetric management
  • ICU: for management of patients with septic shock ^[6]
  • Neonatology: to stabilize premature neonates and evaluate for neonatal sepsis ^[11]

Sepsis is a medical emergency. Monitor closely for early signs of sepsis, and begin treatment immediately if sepsis is suspected. ^[6]

Empiric antibiotics for maternal sepsis ^[12]

• Ampicillin (off-label) ^[12][6]
• PLUS gentamicin (off-label) ^[12][6]
• PLUS clindamycin OR metronidazole (off-label) ^[12][6]

Management of maternal septic shock ^[6]

• Give fluid boluses (≤ 30 mL/kg) to maintain MAP ≥ 65 mm Hg.
• If vasopressors are required for hypoperfusion, give norepinephrine.
• Consider low-dose steroids if there is insufficient response to vasopressors after 4 hours.
• Initiate deep vein thrombosis prophylaxis.
• Initiate insulin therapy if glucose rises to >180 mg/dL.
• See also "Resuscitation in septic shock."

Obstetric management ^[6]

• Manage as high-risk pregnancy.
• For viable fetuses:
  • Monitor fetal well-being; consider continuous electronic fetal heart rate monitoring.
  • Consider corticosteroids for fetal lung maturation.
• Perform the following as needed for source control:
  • Delivery in patients with intra-amniotic infection
  • Evacuation of retained products of conception

In addition to complications of sepsis in nonpregnant patients, complications of maternal sepsis include: ^[6]

• Placental dysfunction
• Preterm delivery
• Pregnancy loss (e.g., spontaneous abortion, fetal demise)
• Infertility (e.g., due to sepsis-related infection or hysterectomy for infection source control)
• Postsepsis syndrome ^[4]

We list the most important complications. The selection is not exhaustive.