Characteristics of Uterine Activity During Labor After Previous Cesarean Section

Abstract

Uterine activity was studied during labor in 36 women who had previous cesarean sections. There was no difference in uterine activity between those delivered vaginally (66%) or those who needed repeat cesarean section, in overall values or at different cervical dilatations. Measurement of intrauterine pressure and electronic fetal monitoring helped reduce the need for repeat cesarean sections. Section. 1988; 8(3): 198-201 MeSH KEYWORDS: Cesarean section; Labor; Uterine contraction AS Akiel, Characteristics of Uterine Activity During Labor After Previous CesareanIn recent years the cesarean section rate has increased to between 15% and 18.3% of all deliveries in the United States, 1,2 and 23% to 33% 2,3 of these were in patients who had had previous cesarean section. In Ireland, O'Driscoll and Foley 4 reported a 4.3% cesarean section rate, about one quarter of which were due to repeat cesarean section. The advantages of electing repeat cesarean section are small family size, the ability to make advance arrangements for home assistance, and most importantly, a competent hospital team to reduce morbidity and mortality associated with operative deliveries. Sometimes, the expectant mothers are reluctant to accept repeat sections especially for nonrecurring causes. These women require adequate antenatal and intrapartum care, with particular attention to monitoring the scar from previous cesarean section. Antenatal evaluation in patients who have had previous cesarean delivery includes clinical and ultrasound assessment of the pregnancy and fetus, as well as radiologic examination of the pelvis. Careful intrapartum monitoring of maternal and fetal well-being is critical to prevent disastrous consequences.Measurement of intrauterine pressure (uterine activity) is the most reliable method of quantitating uterine work in labor. [5][6][7] The active contraction area recorded is the integral of pressure above baseline tone with time (uterine activity integral [UAI] expressed in SI units as kilopascal seconds) is the most important single variable determining the rate of cervical dilatation. 8,9 This study reports the values of UAI during spontaneous unaugmented labor in women who have had previous cesarean section. Patients and MethodsA prospective study was conducted on 36 women of Arabic origin in spontaneous labor who were delivered by cesarean section in their immediately previous pregnancy. The decision to attempt a trial of the cesarean scar was made by the obstetrician in charge of the patient prior to admission. Patients were considered to be suitable for a trial of the cesarean scar if pregnancy had been uncomplicated, presentation was cephalic, pelvimetry was adequate on clinical assessment (the anteroposterior diameter of the pelvic inlet more than 10 cm on erect lateral X-ray pelvimetry), and fetal weight was average clinically and by ultrasound (fetal weight assessment using abdominal