Here’s another video for you in regards to the importance of continuous monitoring during your VBAC. As always information is after the video.
Continuous Electronic Fetal Monitoring and VBAC:
“Prolonged, late, or recurrent variable decelerations or fetal bradycardias are often the first and only signs of uterine rupture. Bujold and Gauthier showed that abnormal patterns in fetal heart rate were the first manifestations of uterine rupture in 87% of patients. In a study by Leung et al, prolonged decelerations in fetal heart rate occurred in 79% of cases and were the most common finding associated with uterine rupture. Rodriguez et al found that fetal distress was the most common finding associated with uterine rupture, occurring in 78%. Overall, in 4 studies from 1983-2000, prolonged decelerations of fetal heart rate or bradycardias occurred in 114 (80%) of 143 cases of uterine rupture. In cases that involved the extrusion of the placenta and fetus into the abdominal cavity, prolonged decelerations in fetal heart rate invariably occurred.[64, 88, 90, 91]
“Sudden or atypical maternal abdominal pain occurs more rarely than fetal heart rate decelerations or bradycardia. In 9 studies from 1980-2002, abdominal pain occurred in 13-60% of cases of uterine rupture. In a review of 10,967 patients undergoing a TOLAC, only 22% of complete uterine ruptures presented with abdominal pain and 76% presented with signs of fetal distress diagnosed by continuous electronic fetal monitoring.
“Moreover, in a study by Bujold and Gauthier, abdominal pain was the first sign of rupture in only 5% of patients and occurred in women who developed uterine rupture without epidural analgesia but not in women who received an epidural block. Thus, abdominal pain is an unreliable and uncommon sign of uterine rupture. Initial concerns that epidural anesthesia might mask the pain caused by uterine rupture have not been verified and there have been no reports of epidural anesthesia delaying the diagnosis of uterine rupture. The ACOG guideline from 2010 suggests there is no absolute contraindication to epidural anesthesia for a TOLAC because epidurals rarely mask the signs and symptoms of uterine rupture.
“Phelan et al found that abnormal patterns of uterine activity, such as tetany and hyperstimulation, are often not associated with uterine rupture. In their study, in which monitoring of uterine activity was limited to external tocodynamometry, tetany was defined as a contraction lasting longer than 90 seconds, and hyperstimulation was defined as more than 5 contractions in 10 minutes. Rodriguez et al found that the usefulness of intrauterine pressure catheters (IUPCs) for diagnosing uterine rupture was not supported. In 76 cases of uterine rupture, the classic description of decreased uterine tone and diminished uterine activity was not observed in any patients, 39 of whom had IUPCs in place. In addition, rates of fetal and maternal morbidity and mortality associated with uterine rupture did not differ with the use of an IUPC compared with external tocodynamometry.
“In 8 reports published from 1980-2002 in which investigators examined the frequency of vaginal bleeding in cases of uterine rupture, vaginal bleeding occurred in 11-67% of cases. In 3 studies, maternal shock from hypovolemia was associated with uterine rupture in 29-46% of cases.[2, 5, 94] “
ACOG and RCOG agree that CEFM is the most accurate indicator of uterine rupture:
“Both groups recommend continuous electronic fetal monitoring and intrapartum care for the duration of planned VBAC to enable prompt identification and management of uterine scar rupture. According to ACOG, uterine rupture is often sudden and may be catastrophic, and accurate antenatal predictors of uterine rupture do not exist. RCOG similarly notes that there is no single pathognomic clinical feature that is indicative of uterine rupture. Both groups agree, however, that signs/symptoms of uterine rupture to be vigilant for include: fetal and/or maternal heart rate abnormality; loss of fetal station of the presenting part; excessive vaginal bleeding or hematuria; and new onset of uterine scar pain/tenderness. ACOG also cites increased uterine contractions; RCOG also cites severe abdominal pain, chest pain or shoulder tip pain, and cessation of previously efficient uterine activity.
“There is further agreement that epidural analgesia may be used in planned VBAC. ACOG notes that adequate pain relief may encourage more women to choose TOLAC. They add that effective regional analgesia should not be expected to mask signs and symptoms of uterine rupture, particularly because the most common sign of rupture is fetal heart tracing abnormalities.”
Dr. Bridget Tobin explains CEFM and its importance for VBACs at “VBAC and Birth After Cesarean Facts — Evidence Based Support” Facebook group (Membership may be required to read this post):
More discussion of EFM from the American Academy of Family Physicians: http://www.aafp.org/afp/2009/1215/p1388.html