Mechanical induction of labor and ecbolic-less vaginal birth after cesarean section: A cohort study

Analysis of Maternal and Infant Outcomes and Related Factors of Vaginal Delivery of Second Pregnancy after Cesarean Section

Objective

To explore the clinical effect of different delivery methods and the safety of vaginal delivery of second pregnancy after cesarean section and analyze the related factors.

Methods

A total of 738 eligible pregnant women who underwent cesarean section from September 2018 to August 2020 were randomly selected from our hospital. Among them, 527 pregnant women successfully delivered vaginally were selected as the observation group, and 211 pregnant women who failed vaginal delivery were selected as the control group. To analyze the factors that influence the success of vaginal delivery of second pregnancy after cesarean section and compare the outcomes of mother and infant in two groups.

Results

There was no significant difference in age, prenatal body mass index (BMI), and thickness of lower uterine segment between the two groups (P > 0.05). There were significant differences in fetal head orientation, fetal abdominal circumference, fetal biparietal diameter, uterine height, premature rupture of membranes, Bishop score, and epidural anesthesia during labor between the two groups (P < 0.05). Multivariate logistic regression analysis showed that fetal abdominal circumference, fetal head orientation, Bishop score, and epidural anesthesia during labor were independent factors affecting the success of VBAC (P < 0.05). There was no significant difference in the incidence of uterine rupture between the two groups (P > 0.05). The amount of postpartum hemorrhage in the observation group was significantly lower than that in the control group (P < 0.05). There was no significant difference in Apgar score, asphyxia rate, and hospitalization rate between the two groups (P > 0.05). There was no significant difference in the incidence of complications between the two groups (P > 0.05).

Conclusion

There are many factors that influence the success of vaginal delivery after cesarean section. Through prenatal comprehensive evaluation of vaginal delivery conditions, we can guide the parturient to choose a reasonable mode of delivery, reduce the incidence of complications, and improve the outcome of mother and baby.

Mechanical Methods for the Induction of Labour After Previous Caesarean Section – An Updated, Evidence-based Review

There are currently no up-to-date evidence-based recommendations on the preferred method to induce labour after previous Caesarean section, especially for patients with unripe cervix, as randomised controlled studies are lacking. Intravenous oxytocin and misoprostol are contraindicated in these women because of the high risk of uterine rupture. In women with ripe cervix (Bishop Score > 6), intravenous administration of oxytocin is an effective procedure with comparable rates of uterine rupture to those with spontaneous onset of labour. Vaginal prostaglandin E ₂ (PGE ₂ ) and mechanical methods (balloon catheters, hygroscopic cervical dilators) are effective methods to induce labour in pregnant women with unripe cervix and previous Caesarean section. According to current guidelines, the administration of PGE ₂ is associated with a higher rate of uterine rupture compared to balloon catheters. Balloon catheters are therefore a suitable alternative to PGE ₂ to induce labour after previous Caesarean section, even though this is an off-label use. In addition to two meta-analyses published in 2016, 12 mostly retrospective cohort/observational studies with low to moderate levels of evidence have been published on mechanical methods of cervical ripening after previous Caesarean section. But because of the significant heterogeneity of the studies, substantial differences in study design, and insufficient numbers of pregnant women included in the studies, it is not possible to make any evidence-based recommendations based on these studies. According to a recent meta-analysis, the average rate using balloon catheters is approximately 53% and the average rate after spontaneous onset of labour is 72%. The uterine rupture rate was 0.2–0.9% for vaginal PGE ₂ and 0.56–0.94% for balloon catheters and is therefore comparable to the uterine rupture rate associated with spontaneous onset of labour. According to the product informations, hygroscopic cervical dilators (Dilapan-S) are currently the only method which is not contraindicated for cervical ripening/induction of labour in women with previous Caesarean section, although data are insufficient. Well-designed, randomised, controlled studies with sufficient case numbers comparing balloon catheters and hygroscopic cervical dilators with mechanical methods and vaginal prostaglandin E ₂ /oral misoprostol are therefore necessary to allow proper decision-making.

Epidemiology of uterine rupture among pregnant women in China and development of a risk prediction model: analysis of data from a multicentre, cross-sectional study

OBJECTIVES

To describe the epidemiology of uterine rupture in China from 2015 to 2016 and to build a prediction model for uterine rupture in women with a scarred uterus.

SETTING

A multicentre cross-sectional survey conducted in 96 hospitals across China in 2015-2016.

PARTICIPANTS

Our survey initially included 77 789 birth records from hospitals with 1000 or more deliveries per year. We excluded 2567 births less than 24 gestational weeks or unknown and 1042 births with unknown status of uterine rupture, leaving 74 180 births for the final analysis.

PRIMARY AND SECONDARY OUTCOME MEASURES

Complete and incomplete uterine rupture and the risk factors, and a prediction model for uterine rupture in women with scarred uterus (assigned each birth a weight based on the sampling frame).

RESULTS

The weighted incidence of uterine rupture was 0.18% (95% CI 0.05% to 0.23%) in our study population during 2015 and 2016. The weighted incidence of uterine rupture in women with scarred and intact uterus was 0.79% (95% CI 0.63% to 0.91%) and 0.05% (95% CI 0.02% to 0.13%), respectively. Younger or older maternal age, prepregnancy diabetes, overweight or obesity, complications during pregnancy (hypertensive disorders in pregnancy and gestational diabetes), low education, repeat caesarean section (≥2), multiple abortions (≥2), assisted reproductive technology, placenta previa, induce labour, fetal malpresentation, multiple pregnancy, anaemia, high parity and antepartum stillbirth were associated with an increased risk of uterine rupture. The prediction model including eight variables (OR >1.5) yielded an area under the curve (AUC) of 0.812 (95% CI 0.793 to 0.836) in predicting uterine rupture in women with scarred uterus with sensitivity and specificity of 77.2% and 69.8%, respectively.

CONCLUSIONS

The incidence of uterine rupture was 0.18% in this population in 2015-2016. The predictive model based on eight easily available variables had a moderate predictive value in predicting uterine rupture in women with scarred uterus. Strategies based on predictions may be considered to further reduce the burden of uterine rupture in China.

Using dinoprostone vaginal insert for induction of labor: A single institute experience

OBJECTIVE

To evaluate the factors associated with the successful induction of labor (IOL) in women treated with dinoprostone slow-released vaginal insert.

MATERIAL AND METHODS

A retrospective study was conducted between June 2017 and December 2017, enrolling 65 patients who underwent dinoprostone slow-released vaginal insert-induced labor. The correlation between the characteristics of the pregnant women and its success, as well as perinatal complications and adverse outcomes were analyzed.

RESULTS

Fifty-three of 65 (81.5%) achieved a successful vaginal delivery. Only multi-parous pregnant women were an independent predictor factor for successful induction after dinoprostone slow-released vaginal insert, since all of them succeeded after this strategy treatment (100%, n = 18), compared to 74.5% (35/47) of successful rate in the nulliparous pregnant women with a statistically significant difference (p = 0.018). There were no adverse events occurred in both mothers and their offspring.

CONCLUSION

Dinoprostone slow-released vaginal insert is a good choice for multiparous pregnant women who need IOL, regardless of which reasons are indicated. For nulliparous women, more studies might be needed to evaluate the effectiveness of PGE2 for IOL.

Intracervical Foley Catheter Plus Intravaginal Misoprostol vs Intravaginal Misoprostol Alone for Cervical Ripening: A Meta-Analysis

Currently, there is no meta-analysis comparing intravaginal misoprostol plus intracervical Foley catheter versus intravaginal misoprostol alone for term pregnancy without identifying risk factors. Therefore, the purpose of this study is to conduct a systematic review and meta-analysis of randomized control trials (RCTs) comparing concurrent intravaginal misoprostol and intracervical Foley catheter versus intravaginal misoprostol alone for cervical ripening. We systematically searched Embase, Pubmed, and Cochrane Collaboration databases for randomized controlled trials (RCTs) comparing intracervical Foley catheter plus intravaginal misoprostol and intravaginal misoprostol alone using the search terms "Foley", "misoprostol", "cervical ripening", and "induction" up to 29 January 2019. Data were extracted and analyzed by two independent reviewers including study characteristics, induction time, cesarean section (C/S), clinical suspicion of chorioamnionitis, uterine tachysystole, meconium stain, and neonatal intensive care unit (NICU) admissions. Data was pooled using random effects modeling and calculated with risk ratio (RR) and 95% confidence interval (CI). Pooled analysis from eight studies, including 1110 women, showed that labor induction using a combination of intracervical Foley catheter and intravaginal misoprostol decreased induction time by 2.71 h (95% CI -4.33 to -1.08, p = 0.001), as well as the risk of uterine tachysystole and meconium staining (RR 0.54, 95% CI 0.30-0.99 and RR 0.48, 95% CI 0.32-0.73, respectively) significantly compared to those using intravaginal misoprostol alone. However, there was no difference in C/S rate (RR 0.93, 95% CI 0.78-1.11) or clinical suspicion of chorioamnionitis rate (RR 1.22, CI 0.58-2.57) between the two groups. Labor induction with a combination of intracervical Foley catheter and intravaginal misoprostol may be a better choice based on advantages in shortening induction time and reducing the risk of uterine tachysystole and meconium staining compared to intravaginal misoprostol alone.