Clinical Analysis On The Effectiveness Of Transvaginal Cervical Cerclage In Singleton Pregnancies And Its Predictive Factors

Background:Cervical insufficiency is described as the inability of the uterine cervix to support a full-term pregnancy due to a functional or structural defect of the cervix.It is most classically associated with painless,progressive dilatation of the uterine cervix in the second or early third trimester resulting in membrane prolapse,premature rupture of membranes(PROM),mid-trimester pregnancy loss,or preterm birth.Its incidence rate is between 0.1%-2%of the obstetric population and is estimated to account for 15%of the habitual abortion between 16 and 28 weeks.It is an important contributor to preterm birth(PTB).PTB is estimated to be about 13 million worldwide annually,and more than 1 million infants die from its complications.Although the neonatal care in China had improved dramatically over the past few years,the survival rate of infants born before 28 weeks of gestation is<50%with the significant number of the surviving infants moderately to severely handicapped.This creates an emotional and physical distress environment for the mother and her families.Therefore,it becomes a great challenge for the obstetricians to prevent the PTB and recurrent second-trimester losses caused by cervical insufficiency.Though controversial,transvaginal cervical cerclage remained the mainstay in the treatment of cervical incompetence for several decades.Some studies have reported that women who have undergone cerclage when compared with women with a similar history of cervical incompetence treated with bed rest or tocolytics,the former has had more favorable outcomes in the prolongation of pregnancy and neonatal survival.In this study,we evaluate the effectiveness of transvaginal cerclage by McDonald’s technique in singleton pregnancies and determine the predictive factors affecting its outcome,followed by the comparison of elective and emergency cerclage regarding prolongation of pregnancy,complications,and neonatal outcomes.This information may help the patient and her caretaker in making a decision whether to undergo transvaginal cervical cerclage either electively or as an emergency procedure.Objective:To evaluate the effectiveness of transvaginal cervical cerclage in singleton pregnancies with cervical incompetence and determine the predictive factors of success and failure.To compare the effectiveness of elective and emergency cerclage in prolonging the pregnancy,complications,and neonatal outcomes.Methods:This was a retrospective observational study of 62 patients who underwent transvaginal cervical cerclage for cervical incompetence in The First Bethune Hospital of Jilin University,ChangChun,China,between May 2015 and January 2018.Patients who underwent cerclage placement and delivered in the ward were identified using an existing database.Women with a singleton gestation who underwent elective cerclage and emergency cerclage were included for study.Exclusion criteria(n=42,40.4%)included:(1)Unavailable medical records and lost to follow-up;(2)Multiple gestations;(3)Laparoscopic cerclage;(4)Delivered due to maternal/fetal indication such as chronic medical condition:seizures,psychiatric disorders,uncontrolled hypertension,fetal distress;likely to interfere the treatment;(5)Patients with clinical infection(axillary temperature>37.5~?C,serum WBC>14×10~9/L,C-reactive protein(CRP)>10mg/dL);6)Patients with uterine contractions;(7)Patients with leaking per vaginum,bleeding per vaginum.Among the inclusion criteria(n=62),patients included in the elective group(n=48,77.4%)had the cerclage placed between 12-16 weeks based on their poor obstetrical history and/or risk factors:a history of multiple prior preterm births and/or second-trimester losses(STL).Patients were allocated to the emergency cerclage group(n=14,22.6%)when the diagnosis of cervical dilatation and membrane protruding was made by physical examination as patients complained about pelvic pressure sensation or increased clear vaginal discharge and asymptomatic patients were diagnosed by cervical ultrasound screening(cervical length≤2.5cm;internal os≥8mm;funneling of cervix).All patients received McDonald cerclage under spinal anesthesia,performed by consultant obstetrician following exclusion of fetal anomalies and assessment of viability by ultrasound.Moreover,before placement,a high vaginal swab was taken for microbiological analyses,culture,and drug sensitivity.If active infections,treated with antibiotics before cerclage placement.All the maternal medical records were reviewed and the following data were extracted and analyzed:maternal demographic factors(including maternal age,gravidity,parity,prior obstetric history),clinical data(cervical length and dilatation at the time of cerclage),operative details(gestation at cerclage,types of cerclage,and cerclage technique),suture to delivery interval,gestational age at delivery time,mode of delivery,complications after treatment,and neonatal outcomes data(fetal survival rate,term and preterm birth rate,neonatal hospitalization rate,neonatal death rate,neonatal birth weight,APGAR scores).Firstly,the neonatal outcomes of the successful group were analyzed,followed by determination of the predictive factors affecting the success and failure of the obstetric outcome.They were defined as the successful group who delivered the live babies and the failure group who experienced abortion or stillbirth.Then we divided all cases into elective and emergency cerclage group.Lastly,we performed the analysis by comparing the effectiveness of elective and emergency cerclage group in prolonging the pregnancy,neonatal outcomes,and complications.Data were analyzed using the statistical software package IBM SPSS Statistics 21.Data were expressed as mean(M)±standard deviation(SD)if normally distributed,and Independent sample t-test was used for statistical comparison.Non normally distributed data were expressed as Median(Range),and analysis was performed using Mann-Whitney-Wilcoxon test.Categorical variables are summarized by frequencies and percentages with P-values from a Fischer’s Exact test and Chi-squared test wherever appropriate.A two-sided P value<0.05 was considered to be statistically significant.Results:Out of 104 patients,sixty-two patients met inclusion criteria.(A)In the 62 cases,47(75.8%)cases succeeded,and 15(24.2%)cases failed.In the successful group,21(44.7%)women delivered pretermly and 26(55.3%)delivered termly.In terms of mode of delivery,the proportion of cesarean section was higher than vaginal delivery(70.2%vs.29.8%).The proportion of neonates born with birth weight≥2500g(80.9%)were higher compared to that of birth weight<2500g(19.1%).The mean Apgar score of neonates born beyond 27.29 weeks was 8.31±1.52(range:5-10)at 1 min and 9.29±0.96(range:7-10)at 5 min.No severe maternal complications occurred except cervical laceration(2 cases,3.23%),premature rupture of membranes(13,20.97%).(B)In the 62 cases,40(64.5%)women have≤2 previous second-trimester losses and 22(35.5%)women have>2 previous second-trimester losses.No significant differences were found regarding neonatal outcomes(all P>0.05)between these two groups.(C)Analysis revealed that the higher postoperative C-reactive protein value and presence of premature rupture of membranes were the strongest predictors of cerclage failure.However,no significant differences was seen in preoperative leucocyte value between the success and failure group.(D)Among the 62 cases,48(77.4%)cases were included in elective cerclage group with the mean gestational age 15.04±1.25 weeks;and 14(22.6%)cases were allocated in emergency cerclage group with the mean gestational age 20.15±4.64 weeks.Regarding pregnancy outcomes,as anticipated,pregnancy prolongation was significantly more(P=0.014)in the elective group with a median of 21 weeks(range:1-27 weeks)compared to that of the emergency group with a median of 11.65 weeks(range:1-25 weeks).However,no significant differences were found either in gestational age at delivery or in the frequency of premature rupture of membrane(P>0.05).There were no significant differences in the neonatal outcomes between the emergency and the elective groups,such as live birth rate,term birth rate,fetal death rate,neonatal hospitalization rate,live neonatal weight,and Apgar at 1 min(all P>0.05).However,only the Apgar score at 5 min showed significantly higher score in the elective group than that of the emergency group(P=0.042).Conclusions:The possibility of achieving 75.8%live births proves that transvaginal cervical cerclage is an effective and safe technique in prolonging the gestational age,improving the obstetric outcomes in singleton pregnancies with cervical incompetence under various cerclage indications.There are no differences in neonatal outcomes between women with the history of≤2 previous second-trimester losses and women with the history of>2 previous second-trimester losses.Pregnancy prolongation,gestation at delivery,postoperative C-reactive protein,and premature rupture of membranes are the predictive factors related to success or failure of transvaginal cervical cerclage.Though elective cerclage appears to be significantly more effective in prolonging the pregnancy as compared to emergency cerclage,yet no significant differences are seen regarding neonatal outcomes and complications between them.No matter what kind of cervical cerclage performed,we should reduce or even avoid the risks of postoperative infection of cervical cerclage through the predictors of inflammatory markers(mainly postoperative C-reactive protein value)to achieve maximum success rates.