Maternal intrapartum fever, or pyrexia, is a body temperature of 100.4°F (38°C) or higher during labor. This elevation prompts close monitoring of both the birthing person and the baby. It affects 1-2% of deliveries, and healthcare teams are prepared to manage it.
Causes of Fever During Labor
Chorioamnionitis, an inflammation of the fetal membranes and amniotic fluid, is a primary infectious cause of fever during labor. It develops when bacteria ascend from the vagina into the uterus, especially after membranes rupture. Prolonged rupture of membranes and frequent vaginal examinations increase this risk.
Non-infectious causes of fever include epidural analgesia. Epidural-associated fever, affecting 15-25% of those who receive an epidural, is an inflammatory response to the medication, not an infection. This response involves elevated inflammatory mediators like interleukin-6 (IL-6) and altered thermoregulation, such as reduced heat dissipation. The duration of epidural exposure correlates with the likelihood of developing this fever.
Other factors contributing to fever include dehydration during prolonged labor, physical exertion, and stress. Less commonly, general infections like urinary tract or respiratory infections can also cause fever.
Potential Effects on Mother and Baby
Maternal fever can influence labor and the birthing person’s health. It may decrease uterine contractions, potentially increasing the likelihood of interventions like cesarean delivery. Postpartum infections and an elevated risk of hemorrhage are also possible.
For the baby, maternal fever can present several issues. Fetal tachycardia, an elevated heart rate, is a common sign. Babies born to birthing people with intrapartum fever may have lower Apgar scores, indicating a need for closer observation after delivery.
The newborn may require evaluation for neonatal sepsis, an infection in the bloodstream, potentially necessitating a NICU stay for observation and antibiotic treatment. Elevated maternal temperatures can also link to neonatal encephalopathy, respiratory distress syndrome, or seizures. This is partly because the fetal core temperature can exceed the maternal temperature during fever.
Medical Management and Treatment
Upon detecting fever, healthcare providers closely monitor both the birthing person and the baby. Maternal vital signs (temperature, pulse, blood pressure, respiratory rate) are frequently checked, often every 15 minutes to four hours. Continuous fetal heart rate monitoring assesses the baby’s well-being.
Diagnostic tests determine the fever’s cause. Blood work, such as a complete blood count and C-reactive protein (CRP), is often ordered for infection signs. Blood cultures may be taken, ideally before antibiotic administration, to identify bacteria. A urine dipstick or culture can rule out a urinary tract infection.
Treatment protocols for intrapartum fever involve several steps. Intravenous (IV) fluids are administered for hydration and to lower body temperature. Antipyretics, such as acetaminophen, reduce the fever.
Broad-spectrum antibiotics are frequently initiated, often before a definitive infection is confirmed. This precaution covers common bacteria, including Group B Streptococcus (GBS), protecting both the birthing person and the baby. The specific antibiotic regimen, which might include ampicillin and gentamicin, can be adjusted based on the suspected infection source or if a cesarean delivery is performed, potentially adding clindamycin or metronidazole.