Fever, uterine tenderness, increased white blood cell count, and foul-smelling amniotic fluid are all signs of amnionitis in labor. Once amnionitis is suspected as the cause of infection in a pregnant patient, it is important to start antibiotics as soon as possible to fight the infection.
Once amnionitis has been diagnosed, the baby needs to be delivered immediately, regardless of the due date. Even the most powerful antibiotics cannot successfully treat an infection in the uterus while the fetus, membranes, and placenta remain inside. Therefore, the mother and fetus are at greatest risk until adequate treatment can be started. Obviously, the length of the pregnancy will affect the fetus's chance for survival.
In the past, doctors did not start antibiotics until the baby was delivered, because antibiotics given to a pregnant mother could erroneously affect results of cultures from the newborn. Culture results could be negative when infection was present. More recent studies have shown both mother and baby benefit from initiation of intravenous antibiotics during labor, with reduced risk of significant infection. In addition, the baby will generally be treated with antibiotics for at least 48 hours after delivery, even if there are no signs or symptoms of infection.
Labor is usually induced when amnionitis is diagnosed; medications may be given to speed up labor if the patient has already started contracting. Cesarean section should be performed only when necessary-for example, in instances of non-reassuring fetal well-being or lack of progress in labor. The presence of infection can affect the ability of the uterus to contract and can increase the likelihood of needing a cesarean section. A pediatrician or neonatologist should be present at the delivery when amnionitis has complicated labor. In rare cases (5%), newborns are septic at delivery; this is a life-threatening infection of the bloodstream requiring emergency measures that the pediatric team must be prepared to handle.
Results of some recent studies support the practice of urgent delivery in cases of uterine infection in the mother. This research has provided evidence that exposure to infection can risk cerebral palsy in the fetus.
Complications of Amnionitis
Recovery from amnionitis can be complicated by endomyometritis (infection of the muscle of the uterus). This complication can be quite serious especially if cesarean section was performed. Endomyometritis can be treated successfully with a combination of intravenous antibiotics. The antibiotics are generally given until the patient has been fever-free for at least 48 hours. Severe cases of endomyometritis can be slow to respond to antibiotics and cause further complications, including developing infected blood clots in the veins of the pelvis. This condition is called septic pelvic thrombophlebitis and may require blood thinners in addition to antibiotics.
The treatment of amnionitis is one of the success stories of modern obstetrics. Prompt recognition and treatment of the infection can lead to a successful delivery of the fetus with minimal complications for the baby and the mother.