In addition to the classic portions of the history of present illness, important details to elicit during history taking include: 

• Time of delivery or abortion
• Surgical or vaginal delivery
• Prior surgical and medical history history
• Gestational age at the time of the delivery or abortion
• Complications of the pregnancy, including gestational diabetes, intrapartum infections, premature or prolonged rupture of membranes, chorioamnionitis, or preeclampsia/eclampsia
• Complications of the delivery, including prolonged labor, need for operative vaginal delivery, unplanned cesarean section, and postpartum hemorrhage 
• GBS status 
• Presence of foul-smelling lochia or excessive vaginal bleeding

Physical examination should include:

• Evaluation of the surgical incision (if present)
• Examination of the skin for crepitance, bullae, erythema, induration or drainage
• Palpation of the abdomen and the uterine fundus
• Sterile speculum and bimanual examination  

In endometritis, fever is often the first sign, with uterine tenderness, bleeding, and foul-smelling lochia as additional signs. Patients presenting with signs of severe systemic illness, shock, and/or abdominal pain out of proportion to examination findings should raise suspicion for infection with GAS, which can cause endometritis associated with toxic shock syndrome as well as necrotizing fasciitis.[11] 

Fever is common in septic abortion but may not be present.[11] Usually, only mild abdominal pain is present, although generalized peritonitis can be seen in severe infection.[11] In addition to GAS, septic abortion associated with sepsis or shock can also occur in the setting of infection with Clostridium species or toxin-producing strains of Escherichia coli.[11]

Superficial incisional site infections typically present with erythema, warmth, and pain at the site; purulent drainage may also be present.[21] These infections occur most commonly 4 to 7 days following surgery; as mentioned above, signs of infection in the first 48 hours should raise suspicion for group A or B streptococci.[15] 

Deep incisional infections may show minimal external examination findings, in fact, pain out of proportion to examination is a hallmark of necrotizing fasciitis. Unlike superficial site infections, deep incisional infections are more likely to be associated with fever and hemodynamic compromise.[15] The examination may show skin necrosis or ecchymosis, crepitus, and bullae.[15] Imaging studies may show gas in the soft tissues, but definitive diagnosis and management are surgical; surgery should not be delayed for diagnostic studies, as these infections are rapidly progressive and fatal if not managed promptly.  

Septic pelvic thrombophlebitis (SPT) should be suspected in patients with persistent pain, leukocytosis, and fever despite adequate antibiotic therapy for the above conditions for more than 3 to 5 days.[15] Deep organ infections such as an infected hematoma or pelvic abscess should likewise be considered if the patient is not responding to appropriate antibiotics.[15]

As in all infectious conditions, evaluation should include blood and/or wound cultures prior to the initiation of antibiotics. Laboratory findings typical of infection include leukocytosis with neutrophilia and a left shift as well as lactic acidosis. Notably, no postpartum infection can be excluded based on lab work alone, and clinicians should not be falsely reassured if laboratory diagnostics are unremarkable. Endometritis is largely a clinical diagnosis. Findings suggestive of endometritis include fever, abdominal tenderness, and foul-smelling lochia. If septic abortion is suspected based on history, an ultrasound should be obtained to evaluate for retained products of conception.[11] 

If the infection has spread to the uterus, gas may be seen in the myometrium on plain film or computed tomography (CT).[11] Surgical site infections are likewise a clinical diagnosis suggested by history and physical examination. If post-surgical deep organ infection is suspected, CT with intravenous contrast may help with diagnosis. Workup for pelvic thrombophlebitis should be initiated if the patient does not defervesce following 3-5 days of appropriately broad-spectrum antibiotics. Pelvic vein thrombosis is typically seen radiologically with CT or magnetic resonance imaging (MRI).[22]

Knowledge of the microbiological profiles of different postpartum infections, local resistance patterns, and the severity of the patient’s illness should guide antibiotic choices. As a general rule, antibiotic regimens, particularly in very sick patients, should have a broad-spectrum of antimicrobial coverage at the beginning and should be narrowed as more clinical evidence from cultures or pathology specimens becomes available. Pharmacists can often help tailor initial antibiotic choices and aid in narrowing the spectrum as care progresses. Consideration should be given to whether the patient is breastfeeding, and all efforts should be made to use antibiotics that will allow the patient to continue breastfeeding safely. 

While antibiotic regimens may differ for specific postpartum infections, the foundation of the treatment of most infectious conditions is the same. In patients with hemodynamic compromise, balanced crystalloid fluids should be given to a maximum of 30 ml/kg of ideal body weight.[23] If mean arterial pressure is persistently below 65 mmHg despite adequate fluid resuscitation, a vasopressor should be started.[23] Broad-spectrum antibiotics should be given as soon as possible, and blood cultures should be obtained before antibiotic administration if doing so does not significantly delay antibiotics.[23] If the infection requires surgical intervention, prompt consultation of a surgical service is of utmost importance.  

The treatment of endometritis varies with severity. Patients with mild, early endometritis may be able to receive outpatient treatment; shared decision-making between the provider and the patient should always precede the decision to treat on an outpatient basis. Intramuscular and oral regimens can also be used in low-resource settings where intravenous antibiotics may not be an option. In patients who are appropriate for outpatient treatment, potential 14-day regimens include clindamycin 600 mg orally every 6 hours plus gentamicin intramuscularly 4.5 mg/kg every 24 hours; amoxicillin-clavulanate 875 mg orally twice daily; cefotetan 2g intramuscularly every 8 hours; meropenem or imipenem-cilastatin 500 mg intramuscularly every 8 hours; or amoxicillin 500 mg and metronidazole 500 mg every 8 hours.[24] 

The listed regimens are safe for breastfeeding patients and resulted in a greater than 85% cure rate in early endometritis.[24] As with all patients receiving outpatient treatment, strict return precautions for worsening symptoms should be given. In patients who will receive intravenous therapy for endometritis, the empiric combination of clindamycin (900 mg every 8 hours or 600 mg every 6 hours) and gentamicin (5 mg/kg daily or 1.5 mg/kg every 8 hours) is the most effective [25]. Ampicillin (3g intravenously every 6 hours) can be added for better coverage of enterococcus and in patients who are GBS positive, as there is increasing resistance to clindamycin among GBS isolates.[15][25] Parenteral therapy should continue until the patient defervesces and their pain improves. Improvement should be seen in 48 to 96 hours. If the patient does not improve, consider a pelvic abscess or infected hematoma, septic pelvic thrombophlebitis, or infection with enterococcus. 

The mainstay of treatment for septic abortion is the removal of the infected products of conception. Broad-spectrum antibiotics should be initiated within an hour of making the diagnosis.[26] In addition to the clindamycin and gentamicin with/or without ampicillin regimen mentioned above, other parenteral regimens include ampicillin (2g every 8 hours), gentamicin (5 mg/kg daily), and metronidazole (500 mg every 12 hours); levofloxacin (500 mg every 12 hours) and metronidazole (500 mg every 12 hours); imipenem (500 mg every 6 hours); piperacillin-tazobactam (4.5 g every 8 hours); or ticarcillin-clavulanate (3.1g every 4 hours).[11] In cases not complicated by a pelvic abscess, intravenous antibiotics should be continued until 48 hours after the patient shows clinical improvement [27]).

For mild superficial surgical infections without systemic symptoms or purulence, an oral course of antibiotics is typically sufficient. A first-generation cephalosporin like cephalexin should be used when there is no associated purulence.[28] If there is superficial purulence without evidence of an abscess, consider possible infection with methicillin-resistant Staphylococcus aureus and expand coverage accordingly.[29] If the area of erythema and induration extends fewer than 5 centimeters from the incision, there are systemic signs of infection, or there is a concern for an underlying abscess, the wound should be opened, explored, cultured, then packed with moist gauze, which should be changed twice daily.[28] Empiric coverage for genitourinary (as above) organisms should be started. 

Necrotizing fasciitis is a surgical emergency that cannot be sufficiently treated with antibiotics. However, pending emergent surgical intervention, broad-spectrum antibiotics should be started. A common regimen is vancomycin and piperacillin-tazobactam with clindamycin, which is used for its anti-toxin activity.[30]

Finally, treatment for SPT is intravenous ampicillin (2 g then 1 g every 4 hours), gentamicin (5 mg/kg daily), and clindamycin (900 mg every 8 hours).[22] The use of heparin remains controversial, as there have been no studies to date that suggest it provides clinical benefit beyond appropriate antibiotic administration.[22]

Postpartum fever is defined as an oral temperature ≥38.0°C (≥100.4°F) on any two of the first 10 days postpartum, excluding the first 24 hours.[31] The first postpartum day is excluded because fevers are common in this period, not associated with increased maternal morbidity, and are typically self-limiting.[31] High temperatures in the postpartum period can be caused by fever or by hyperthermia. Other than infections, deep vein thrombosis, and breast engorgement can also cause fever in the postpartum period. Breast engorgement can be associated with a slight increase in maternal temperature.[32] 

Unfortunately, there is no documented cut-off point for what temperature is too high just to be caused by breast engorgement. The presence of myalgias and breast erythema suggest mastitis rather than engorgement as the diagnosis.[32] It is important to remember that postpartum patients can develop infections exclusive of their puerperal status; screening for common infections like urinary tract infections and pneumonia can be done by history and physical examination. 

Causes of hyperthermia include serotonin syndrome, neuroleptic malignant syndrome, an overdose of sympathomimetic or anticholinergic agents, withdrawal from ethanol or benzodiazepines, aspirin toxicity, and thyroid storm.[33] History and physical examination are the foundation of evaluation for these diagnoses. A review of the patient's medication list and inquiry regarding initiation of new serotonergic or neuroleptic agents, which may be used for postpartum depression or psychosis, can screen for serotonin syndrome and neuroleptic malignant syndrome.[33] 

The hallmark physical examination finding for serotonin syndrome is hyperreflexia and clonus, while for neuroleptic malignant syndrome, lead-pipe rigidity is characteristic.[34] Aspirin toxicity is usually suggested by history; physical examination may show altered mental status, hyperpnea, and abdominal tenderness.[33] 

The overdose of sympathomimetic agents presents with tachycardia, hypertension, diaphoresis, and agitation. Withdrawal from benzodiazepines or ethanol can present with tremors, tachycardia, hypertension, and hyperthermia and progress to seizures.[35] Anticholinergic toxicity is characterized by altered mental status, anhidrotic hyperthermia, mydriasis, flushing, and urinary retention.[36] Finally, delivery can precipitate thyroid storm, which presents with hyperthermia, hyperreflexia, nausea, vomiting, and abdominal pain.[37]

Morbidity from postpartum infections affects 5 to 10% of pregnant patients.[38] The prognosis of puerperal infections is directly related to the severity of the infection. Patients who develop sepsis have estimated mortality of 20%. Mortality for septic shock is approximately 40%.[39]

All postpartum infections can progress to sepsis, bacteremia, shock, and death if not treated appropriately. Necrotizing fasciitis is especially notable for its rapid progression to fulminant infection and death. A notable complication of endometritis and deep space infections of the pelvis is SPT. Endometritis affects the endometrium and myometrium but can progress beyond the uterus to include abscess, peritonitis, and pelvic thrombophlebitis.[40] SPT results from intimal pelvic vein injury caused by adjacent uterine infection, bacteremia, or trauma from vaginal or surgical delivery. Infection can also involve the ovarian veins and the inferior vena cava. Risk factors include cesarean section and chorioamnionitis.[41]

Poor access to healthcare is not only an important risk factor for developing postpartum infections but a direct factor in treatment delays and associated morbidity and mortality.[42] New mothers may delay care secondary to concern that they will be hospitalized away from their baby. Patients with infection following elective abortion may avoid care due to stigma. Postpartum psychiatric conditions and an increase in domestic violence in the peripartum period may likewise inhibit care. Providers should seek to create a non-judgmental environment for these patients to discuss their concerns and share decision-making regarding the need for hospitalization and antibiotic choices.

While many patient economic and health risk factors cannot be modified in the peripartum period, healthcare providers can modify several factors to decrease the patient risk for infection. Care bundles of evidence-proven measures have been shown to reduce infection associated with cesarean delivery.[43] Recommendations for such measures based on the phase of labor are discussed below and are best carried out by an interprofessional team. 

Prior to delivery, interventions can be taken to reduce patient risk for infection. Shaving before delivery should be avoided, and patients should be counseled on this prior to their expected delivery date.[44] In patients with planned surgical delivery, the CDC recommends preoperative showering.[45] While there is no strong evidence for the use of chlorhexidine as the agent of choice, there is limited evidence suggesting its superiority in preventing surgical site infections when compared to soap.[21][44] Peripartum glycemic control is important; while hypoglycemia should be avoided, evidence has shown that maintaining blood sugar <200 mg/dL is associated with a decrease in surgical site infections.[46] Screening and treatment of bacterial vaginosis have likewise been shown to decrease the risk of postpartum endometritis and may decrease the risk of other surgical site infections.[44] An alcohol-based agent should be used to prepare the skin at the anticipated incision site.[21] For cesarean deliveries, preparation of the vagina with a 4% chlorhexidine solution has been shown to reduce the risk of endometritis.[44] In patients with preterm prelabor rupture of membranes, antibiotics should be used until delivery.[47]  

During labor, limiting vaginal examinations during labor and avoiding internal fetal monitoring, if possible, can decrease the risk of postpartum infections.[5] In surgical deliveries, a single dose of prophylactic antibiotics should be given one hour prior to the incision.[21][48] Providers should pay special attention to dosing preoperative antibiotics according to the patient's weight, as many antibiotics require a dose increase in obese patients.[49] While the American College of Obstetricians and Gynecologists (ACOG) does not specifically recommend redosing of preoperative antibiotics in cesarean section, providers should consider re-dosing prophylactic antibiotics if the surgical delivery is greater than 3-4 hours or complicated by hemorrhage.[44] Manual extraction of the placenta should be avoided when possible.[44] Meticulous hand washing, strict adherence to sterile techniques, and limiting operating room traffic can likewise decrease the patient risk for infection.[21] 

Finally, outbreaks of GAS infection in postpartum women have often been linked back to colonized or infected health care providers prompting the CDC to recommend health care worker screening when two or more episodes of postpartum GAS infection cases are identified over a six-month period.[50]