Intrapartum fever is defined as a maternal temperature of 100.4°F (38.0°C) or higher during childbirth. This development requires immediate medical attention due to potential implications for both the birthing parent and the newborn. While a slight temperature elevation can be a physiological response to the physical exertion of labor, a sustained or higher fever often signals an underlying medical concern. Medical teams must quickly assess the cause to determine the correct course of action and prevent complications.
Understanding the Causes of Intrapartum Fever
Intrapartum fever stems from two categories: infectious and non-infectious causes. This distinction is important for gauging severity and guiding treatment. The most serious infectious cause is chorioamnionitis, an inflammation or infection of the fetal membranes, amniotic fluid, and sometimes the placenta. This condition is usually caused by bacteria ascending into the uterus from the vagina, often after membranes have ruptured or if labor is prolonged.
Chorioamnionitis is diagnosed clinically, requiring a maternal fever of 100.4°F or higher alongside signs such as fetal tachycardia, maternal leukocytosis (high white blood cell count), or purulent fluid from the cervix. Bacteria like E. coli or Group B Streptococcus are common culprits in these intrauterine infections, necessitating immediate treatment. Less common infectious causes include a urinary tract infection or a viral upper respiratory infection.
The most frequent non-infectious cause of temperature elevation is the use of neuraxial labor analgesia, commonly known as an epidural. Studies consistently show an association between epidural use and a rise in maternal temperature, with the fever risk increasing the longer the epidural is in use. The exact mechanism is not fully understood. One leading theory suggests it involves altered thermoregulation or a sterile inflammatory response mediated by pro-inflammatory cytokines, rather than a true infection.
Simple factors like dehydration or the strenuous physical activity of labor can also contribute to a temporary rise in body temperature. This type of hyperthermia is generally considered less concerning than an infectious fever. However, it requires careful clinical differentiation because an elevated temperature, regardless of the source, can impact the baby. Every fever must be treated seriously until an infectious source is ruled out.
Immediate Health Implications for Mother and Baby
Fever during labor carries immediate risks, even if non-infectious, due to the effect of high temperatures on the fetus. A common fetal response is tachycardia, a sustained increase in the heart rate, which can signal both maternal fever and potential intrauterine infection. This non-reassuring fetal heart rate pattern often prompts medical interventions to expedite delivery.
For the birthing parent, intrapartum fever is linked to an increased risk of medical interventions, including a higher likelihood of requiring a Cesarean section. Even in low-risk patients, the presence of a fever can double the chance of an operative delivery compared to those who remain afebrile. Postpartum complications are also a concern, such as a prolonged hospital stay and an elevated risk of developing endometritis, a serious infection of the uterine lining.
The consequences for the newborn are important, as the fetus’s temperature is often higher than the mother’s. Elevated maternal temperature, regardless of the cause, is associated with a greater risk of adverse neonatal outcomes. These include lower Apgar scores, hypotonia (low muscle tone), and a greater need for assisted ventilation or cardiopulmonary resuscitation immediately after birth.
When the fever is due to a suspected infection like chorioamnionitis, the most concerning risk for the baby is neonatal sepsis, a bloodstream infection. An infectious fever dramatically increases the baby’s chance of developing this serious condition, which can lead to longer-term complications like neurological injury. Therefore, fever during labor necessitates immediate postpartum observation and testing for the baby to rule out infection.
Clinical Management and Treatment Protocols
Once intrapartum fever is diagnosed, medical management focuses on reducing the temperature and treating the presumed cause to protect the health of the mother and baby. Supportive care measures are initiated immediately to lower the maternal temperature. This includes providing intravenous fluids to treat dehydration and using cooling methods such as removing blankets or applying cool cloths. Acetaminophen (paracetamol) is also administered as an antipyretic to help bring the temperature down.
If an infectious cause like chorioamnionitis cannot be definitively ruled out, broad-spectrum intravenous (IV) antibiotics are started without delay. This empirical treatment is a standardized approach because the consequences of untreated infection outweigh the risks of temporary antibiotic exposure. The regimen is chosen to cover the most likely bacteria, such as Group B Streptococcus, and may include drugs like ampicillin and gentamicin.
Continuous fetal monitoring is maintained throughout management to closely track the baby’s heart rate patterns, looking for signs of distress or persistent tachycardia. The neonatology team is notified early in the process to be prepared for the baby’s arrival. If the mother’s condition deteriorates or if fetal monitoring indicates significant distress, an expedited delivery, often by Cesarean section, may be necessary.
Following delivery, if the mother received antibiotics for suspected infection, the newborn undergoes an infection workup, typically involving blood cultures and a period of observation in the hospital. The mother’s IV antibiotics are usually continued for one to two doses postpartum, or until she has been afebrile for a set period, to ensure the infection is fully treated. This approach aims to quickly resolve the maternal fever and minimize the risk of infection transmission to the newborn.