During pregnancy, a fetus is protected from the outside world by the amniotic sac, a tough, fluid-filled membrane that encircles it. According to the University of Alabama, the membranes rupture before labor starts in around 10 percent of pregnancies; this is called premature rupture of membranes (PROM). Rupture of membranes before 37 weeks is known as preterm premature rupture of membranes (PPROM), which occurs in about 2 percent of pregnancies, according to the University of Alabama. Both PROM and PPROM can cause maternal or fetal complications.
Premature Delivery
PPROM causes one-third of all premature deliveries, according to author Tanya Medina, M.D. Medina's article, "Preterm Premature Rupture of Membranes: Diagnosis and Management," appears in the February 15, 2006 issue of the American Family Physician journal. PPROM leads to fetal death in 1 to 2 percent of cases, according to Medina. While prematurity increases the risk of respiratory distress, infection, gastrointestinal problems and intraventricular hemorrhage, PPROM can cause similar complications even if delivery is delayed for several weeks. Corticosteroids administered to the mother help fetal lungs mature before delivery and decreases respiratory distress syndrome by 15 percent if the fetus will be delivered before 32 weeks, according to Medina.
Infection
PROM can lead to maternal and/or fetal infection. Chorioamnionitis, an infection of the amniotic sac and fluid, occurs in 13 to 60 percent of cases of PROM, according to Medina. Symptoms of chorioamnionitis include fever, rapid maternal and fetal heartbeat, abdominal tenderness and foul-smelling vaginal discharge. Fetal complications of chorioamnionitis include pneumonia, which occurs in 5 to 10 percent of babies, reports Audra Robertson of Brigham and Women's Hospital on Healthline.com. Chorioamnionitis increases the chance for cesarean delivery due to poor labor progress and can cause a maternal bloodstream infection. Group B streptococcus and E. coli bacteria, often found in the vagina, can ascend after PROM and infect the baby, according to the Merck Manual.
Cord Compression
The amniotic fluid allows the umbilical cord to float freely and decreases the risk of fetal entanglement in the cord. Without an adequate amount of amniotic fluid, the risk for cord accidents increases. The cord can prolapse, or fall in front of the opening to the vagina, especially if the baby is still small. As the baby descends in labor, the cord becomes compressed between the cervix and the baby's head, cutting off oxygen to the fetus. An immediate cesarean delivery is necessary to save the baby's life, according to the Merck Manual.
The cord can also be compressed between the side of the uterus and the baby, or become wrapped around the baby's neck or extremities. Cord compression complicates between 32 and 76 percent of deliveries after PPROM, according to Medina.
Placental Abruption
Detachment of the placenta from the uterine wall prior to delivery is known as placental abruption, also known as abruptio placentae. The risk of abruption from PPROM is between 4 and 12 percent, Medina states. Abruptions can cause maternal hemorrhage, leading to maternal or fetal death. Immediate delivery is necessary if placental abruption occurs.
References
- American Family Physician: Preterm Premature Rupture of Membranes; Tanya Medina, M.D., Feb 15, 2006
- University of Alabama Birmingham: Premature Rupture of Membranes
- Merck: Premature Rupture of Membranes
- Dr. Spock: Four Complications Involving the Umbilical Cord; Elisa Ross, M.D.
- Healthline: Infections in Pregnancy: Chorioamnionitis; Audra Robertson, Brigham and Women's Hospital
