Approach to postpartum fever: Clinical sciences

Chapters:

Watch video only

Introduction0:00–0:44

Postpartum fever is a temperature of 38 degrees Celsius or 100.4 degrees Fahrenheit or more on two occasions at least four to six hours apart, excluding the first 24 hours after birth.
Postpartum febrile episodes often resolve without intervention if occurring within the first 24 hours of delivery, and for this reason the threshold for a fever in the first day after delivery is typically set at 39 degrees Celsius or 102.2 degrees Fahrenheit.
The source of a maternal postpartum fever varies based on how many days your patient presents after birth, particularly within the first 7 days postpartum.

Unstable Patient0:44–1:19

Now, if your patient presents with a postpartum fever, you should first perform an ABCDE assessment to determine if your patient is unstable or stable.
If unstable, stabilize their airway, breathing, and circulation. Next, obtain IV access and start fluid resuscitation, and consider starting broad-spectrum intravenous antibiotics.
Place your patient on continuous vital sign monitoring, including blood pressure, heart rate, and oxygen saturation. Finally, if needed, provide supplemental oxygen!

Stable Patient1:19–2:15

Okay, now let’s go back to the ABCDE assessment and take a look at stable patients. Start by obtaining a focused history and physical examination; then obtain labs including a CBC, urinalysis, and urine culture.
Next, review the mode of delivery, and how many days away they are from delivery. Here’s a clinical pearl!
It’s common for patients to have a transient low-grade fever within the first 24 hours postpartum, particularly in patients who delivered vaginally, or who have been treated for an intraamniotic infection.
Other factors that might cause a transient postpartum fever include misoprostol use, dehydration, and epidural analgesia.
However, if your patient has a temperature greater than 39 degrees Celsius or 102.2 degrees Fahrenheit on the first day after delivery, don’t delay looking for a cause!

1-3 days postpartum2:15–4:40

First let’s discuss conditions which can present within the first 1 to 3 days postpartum, starting with endometritis. Your patient will typically present with malaise and lower midline abdominal cramping and pain.
Additionally, they may have more uterine bleeding than expected. Your patient may also have certain risk factors like a positive group B streptococcus, or GBS, status; prolonged labor or prolonged ruptured membranes; or an intraamniotic infection during labor.
Additional risk factors include interventions during delivery, such as a C-section; an operative vaginal delivery, like using forceps or a vacuum extractor to assist with the delivery; or manual removal of the placenta.
On physical examination, vital signs may demonstrate tachycardia, and your patient will usually have a tender uterine fundus.
You may also detect a foul-smelling or purulent lochia. Labs will show an elevated white blood cell, or WBC count, possibly with a left-shift and an upward trend of neutrophils.
Urinalysis and urine culture will be normal. With these findings, diagnose postpartum endometritis.
Time for another clinical pearl! WBC counts will normally increase during labor, and can get as high as 30,000 cells per microliter in the first 24 hours postpartum.
It may take up to a week for the WBC count to return to normal, so be cautious when interpreting the presence of leukocytosis in a patient with postpartum fever, especially during the first week.
Now let’s move on to pyelonephritis. Your patient will typically report dysuria as well as urinary frequency and urgency.
They may also report suprapubic pain, flank pain, and hematuria. On physical examination you may find suprapubic tenderness as well as unilateral costovertebral angle, or CVA tenderness.
The CBC may show an elevated WBC count, possibly with a left-shift; and urinalysis will typically be positive for nitrites and pyuria.
Finally, urine culture will demonstrate greater than 100,000 colony forming units of bacteria per milliliter. In this case, your diagnosis is pyelonephritis.
Now let’s focus on those who experience fever 3 to 5 days postpartum. A significant cause of fever in this time frame is surgical site infection, which could occur following a C-section, but could occur in those who had either a significant vaginal laceration or an episiotomy.

3-5 days postpartum4:40–6:32

Patients will report peri-incisional pain, and purulent discharge with a foul odor. Your patient’s history may also include risk factors like prolonged labor or an intraamniotic infection, which may seed the incisional site and subcutaneous tissue layers at the time of delivery.
There may also be additional risk factors for infection and poor wound healing, including obesity and poorly controlled diabetes mellitus.
On physical examination, you may detect erythema, warmth, purulent discharge, and swelling at the surgical or laceration site.
If your patient’s abdominal incision is infected, remember to explore their wound to look for the presence of a fascial dehiscence.
Laboratory evaluation will show an elevated WBC count with a possible left-shift. The urinalysis and urine culture will be negative.
With these findings, diagnose a surgical site infection. Here’s another clinical pearl!
Patients with a surgical site infection should have a culture and Gram stain of the interior of the wound, taking care not to sample the surrounding skin.
This ensures appropriate antibiotic therapy, particularly in the setting of methicillin-resistant staphylococcus aureus, or MRSA; or other drug-resistant pathogens.
Additionally, if your patient develops systemic symptoms, be sure to collect blood cultures to rule out septicemia. If your patient doesn’t experience a fever until postpartum days 6 or 7, consider a thrombotic disorder, such as deep vein thrombosis, or DVT.

6-7 days postpartum6:32–10:20

While an increased risk of developing a DVT during pregnancy is present as soon as the first trimester, the risk is highest within the first week postpartum.
Now, unlike non-pregnant patients, the thrombus tends to be more proximal, typically in the iliac and iliofemoral veins, and occurs more frequently in the left lower extremity compared to the right.
These patients will typically present with unilateral extremity pain and swelling, and possibly a low grade fever. History might also reveal some risk factors for DVT, with the most important one being a personal history of thrombosis.
Others include having a C-section; obesity; hypertension, preeclampsia or eclampsia; and having an acquired or inherited thrombophilia.
The most reliable physical exam finding is a difference in calf circumference measurements of at least 2 centimeters. You might also be able to palpate the thrombotic vein, which could be erythematous, warm, and tender.
Lab testing is typically not necessary for diagnosis, but in your initial workup for the fever, you will find the CBC, urinalysis, and urine culture are typically normal.
Now, with these history and exam findings, your next step is to obtain a lower extremity compression ultrasound. If that demonstrates poor compressibility of a proximal lower extremity vein, your diagnosis is DVT.
Time for a clinical pearl! While serum D-dimer assays are useful to rule-out DVT in non-pregnant patients, this test is not reliable during pregnancy and postpartum, as physiologic levels are normally elevated.
Okay, let’s move to a more serious thrombotic disorder known as septic pelvic thrombophlebitis. This is a rare condition involving pelvic vein endothelial damage, venous stasis, and the hypercoagulability of pregnancy, where the formation of microclots result in thrombosis of an ovarian vein.
In this case, your patient would have already been treated with antibiotics for 3 to 5 days for a suspected infection but continues to have fever without an identifiable source.
They may also report abdominal, back, or flank pain. Their history may include having a C-section, an intraamniotic infection or endometritis; age younger than 20 years; and multiple gestation.
Physical examination is often unremarkable, but lower abdominal or pelvic tenderness might be present. Rarely, you may palpate a thrombotic vein on the abdomen, known as a palpable cord.
Labs such as CBC, urinalysis, and urine culture are often normal, however you may find a mild elevation in their white blood cell count.
Now, remember that septic pelvic thrombophlebitis is considered a diagnosis of exclusion. At this point you have a fever in a postpartum patient without an identifiable cause, so your next step is to order a CT scan with contrast of the abdomen and pelvis.
Finding a thickened and enlarged venous wall with a filling defect secondary to thrombosis will confirm the diagnosis of septic pelvic thrombophlebitis.
Here’s one last clinical pearl! When the ovarian vein is involved in septic vein thrombosis, it usually occurs on the right side.
This is because the right ovarian vein is longer than the left vein, so it’s more likely to be compressed by an enlarged dextrorotated uterus!
Now let’s talk about patients who are 7 or more days out from delivery. Lactational mastitis should be considered in febrile patients who are breastfeeding and present with unilateral breast pain, along with possible chills and myalgias.

7 days or less postpartum10:20–11:20

Physical exam will demonstrate localized breast erythema, edema, warmth, or tenderness; along with possible reactive axillary lymphadenopathy.
Labs are typically not obtained, however if you did order a CBC, urinalysis, and urine culture as part of your initial fever workup, the CBC may show an elevated WBC count, and the urinalysis and culture would be normal.
Imaging studies are typically not necessary, unless you appreciate a fluctuant and tender mass suspicious for abscess. In the absence of an abscess, your diagnosis in this situation is lactational mastitis.

Variable time from delivery11:20–11:37

Finally, after assessing these causes of postpartum fever, consider and assess for alternative diagnoses that could present at any time after delivery.
These include breast engorgement, retained products of conception, and pelvic abscess. Alright, as a quick recap… Postpartum fever is a temperature of 38 degrees Celsius or 100.4 degrees Fahrenheit or more on two occasions at least four to six hours apart, excluding the first 24 hours after birth.

Review11:37–12:18

Common causes can be considered based on how far out the patient is from delivery, and include postpartum endometritis, pyelonephritis, surgical site infection, DVT, septic pelvic thrombophlebitis, or lactational mastitis.
Additional causes that could occur anytime postpartum include breast engorgement, retained products of conception,