Factors Promoting Vaginal Birth After Caesarean Section; A Retrospective Observational Study

Abstract

There has been an increase in cesarean section rate over the past 20 years, which is not uniform but associated with wide variations between and within countries. This is not a recent phenomenon, a senior obstetrician in 1922 wrote to the British Medical Journal: “The art and science of midwifery have either been lost by the younger generation in this country or will certainly be lost if this mad rage for cesarean section is continued”. This progressive increase in the rate of cesarean section has caused a large burden on the health providing system and this urged many efforts to decrease this rates. Many factors are responsible for this increase the namely, increased safety of the operation due to better anesthesia, antibiotic and blood products. The major obstetric indications for the rising rate of cesarean section are dystocia, previous cesarean birth, breech presentation and fetal distress with repeat cesarean accounting for approximately half of the increased rate. Use of Vaginal Birth After Cesarean (VBAC) is increased significantly as an appropriate manner to decrease the rising rate of cesarean section and the pendulum began to swing away from routine repeat cesarean delivery. Most recent reports support the safety of VBAC in women with one or two prior. Elective termination of pregnancy by repeat C.S will continue to be a part of modem obstetric practice, as it offers a number of advantages over a trial of labour including avoidance of rupture scar during labour with its great squeals and the decreased possibility of aspiration pneumonia and infection when a trial of labour has to be terminated by emergent C.S. However, elective repeat cesarean section carries the risk of prematurity and RDS, and to avoid this complication either to wait for the onset of labour or perform C.S at 39 weeks depending on established guideliness for timing an elective repeat C.S as; sure dates of last menstrual period, U/S done early at 10 -12 weeks of pregnancy confirm gestational age or documented fetal heart tones at 20 weeks gestation by non electronic fetoscope or at 10 weeks gestation by Doppler. Prerequisites for trial of labor after previous cesarean delivery according to (ACOG, 2010) include: one or two previous low transverse C.S. with no vertical extension into the fundus or lower uterine segment, cephalic vertex presentation and adequate pelvis with availability of anaesthesia, blood banking service, personnel for continuous monitoring of the mother and fetus and capable of doing emergency cesarean section within 20 - 30 minutes if needed. In our study 252 cases with a history of one Cesarean section presented in labor at Ain Shams University Maternity Hospital from first of January 2014 to 31 December 2014, 93 of them delivered by VBAC (Percentage of VBAC: 36.9%) while 159 delivered by repeated cesarean section. Factors which were found to be significantly affecting the success of TOL include history of vaginal delivery, degree of Bishop score at time of admission. The best chance of successful TOL was obtained by those patients who had prior vaginal delivery especially when it occur after and both after and before previous CS. The most common factor affected success rate of TOL was Bishop score of patient at time of admission .it was higher in patients with Bishop score 4 and more Furthermore regarding complications of delivery the incidence of rupture uterus was 0.8% (n=2) among all patient. The overall incidence of hysterectomy in present study was 0.4% (n=1) due to un repairable rupture uterine scar. The overall incidence of bladder injury in present study was 0.8% (n=2). The indication include during repeat CS and during hysterectomy. According to available records, the overall incidence of blood transfusion was 1.2% (n=3). Also according to available records, the overall incidence of neonatal intensive care unit admission was 0.8% (n=2). Post cesarean uterine rupture is considered the most important complication of a trial of labour. It may be complete and this the usual type with upper segment scars and it results in perinatal death and threatens the maternal life as it is usually associated severe bleeding. Incomplete rupture is usually asymptomatic with no severe bleeding and this is the usual type of rupture in cases of lower segments scars. This type associated with a little morbidity of the mother or fetus. Fetal risks during trial of labour are reduced by strict monitoring of the fetus all through the trial and by the presence of a competent team capable of performing an emergency cesarean section.