Results of Induction of Labor with Prostaglandins E1 and E2 (The RIPE Study): A Real-World Data Analysis of Obstetrical Effectiveness and Clinical Outcomes of Pharmacological Induction of Labor with Vaginal Inserts

Despite extensive knowledge of the mechanisms responsible for childbirth, the course of labor induction is often unpredictable. Therefore, labor induction protocols using prostaglandin analogs have been developed and tested to assess their effectiveness in labor induction unequivocally. A total of 402 women were collected into two groups-receiving vaginal Misoprostol or vaginal Dinoprostone for induction of labor (IOL). Then, the patients were compared in groups depending on the agent they received and their gestational age. Most patients delivered within 48 h, and most of these patients had vaginal parturition. Patients who received the Dinoprostone vaginal insert required statistically significantly more oxytocin administration than patients who received the Misoprostol vaginal insert. Patients who received the Misoprostol vaginal insert used anesthesia during labor statistically more often. Patients who received Misoprostol vaginal inserts had a statistically significantly shorter time to delivery than those with Dinoprostone vaginal inserts. The prevalence of hyperstimulation was similar in all groups and remained low. Vaginal Misoprostol-based IOL is characterized by a shortened time to delivery irrespective of the parturition type, and a lower need for oxytocin augmentation, but also by an increased demand for intrapartum analgesia administration. A vaginal Dinoprostone-based IOL protocol might be considered a more harmonious and desirable option in modern perinatal care.

The Efficacy of Misoprostol Vaginal Inserts for Induction of Labor in Women with Very Unfavorable Cervices

BACKGROUND

The purpose of the present study was to evaluate the effectiveness of a misoprostol vaginal insert as an induction-of-labor (IOL) agent in women with an unfavorable cervix (Bishop score < 2) in achieving vaginal delivery (VD) within 48 h, depending on the gestational week, with particular emphasis on the cesarean section (CS) percentage, intrapartum analgesia application and possible side effects, such as tachysystole ratio.

METHODS

In this retrospective observational study involving 6000 screened pregnant patients, 190 women (3%) fulfilled the study inclusion criteria and underwent vaginal misoprostol IOL. The pregnant women were collected into three groups: patients who delivered at up to 37 weeks of gestation (<37 Group)-42 patients; patients who delivered between 37 and 41 weeks of gestation (37-41 Group)-76 patients; and patients who delivered after 41 weeks of gestation (41+ Group)-72 patients. The outcomes included time to delivery and mode of delivery, rate of tachysystole, need for intrapartum analgesia, and need for oxytocin augmentation.

RESULTS

Most of the patients delivered vaginally (54.8% in <37 Group vs. 57.9% in 37-41 Group vs. 61.1% in 41+ Group). A total of 89.5% (170/190) of patients delivered within 48 h (<37 Group-78.6% vs. 37-41 Group-89.5% vs. 41+ Group-95.8%). Statistical significance was demonstrated for the increased rate of vaginal deliveries and shortened time to delivery in the 41+ weeks group (p = 0.0026 and p = 0.0038). The indications for cesarean section were as follows: abnormal CTG pattern vs. lack of labor progression: 42.1% vs. 57.9% in <37 Group, 59.4% vs. 40.6% in 37-41 Group and 71.4% vs. 28.6% in 41+ Group. Statistical significance was demonstrated for the increased rate of abnormal CTG patterns as cesarean section indications in the 41+ Group (p = 0.0019). The need for oxytocin augmentation in each group was: 35.7% in <37 Group vs. 19.7% in 37-41 Group vs. 11.1% in 41+ Group. Statistical significance was shown for decreased need for oxytocin augmentation in +41 Group (p = 0.0016). The need for intrapartum anesthesia, depending on the group, was: 78.6% in <37 Group vs. 82.9% in 37-41 Group vs. 83.3% in 41+ Group. Statistical significance was demonstrated for increased need for intrapartum anesthesia application during labor in +41 Group (p = 0.0018). The prevalence of hyperstimulation was similar in all three groups (4.8% vs. 7.9% vs. 5.6% p > 0.05).

CONCLUSIONS

The misoprostol vaginal regimen for IOL used in our study is effective in achieving vaginal delivery within 48 h. In post-term women, the use of this regimen is characterized by an increased rate of vaginal deliveries, a shorter time to delivery and a lower need for oxytocin.

Signaling Pathways Regulating Human Cervical Ripening in Preterm and Term Delivery

At the end of gestation, the cervical tissue changes profoundly. As a result of these changes, the uterine cervix becomes soft and vulnerable to dilation. The process occurring in the cervical tissue can be described as cervical ripening. The ripening is a process derivative of enzymatic breakdown and inflammatory response. Therefore, it is apparent that cervical remodeling is a derivative of the reactions mediated by multiple factors such as hormones, prostaglandins, nitric oxide, and inflammatory cytokines. However, despite the research carried out over the years, the cellular pathways responsible for regulating this process are still poorly understood. A comprehensive understanding of the entire process of cervical ripening seems crucial in the context of labor induction. Greater knowledge could provide us with the means to help women who suffer from dysfunctional labor. The overall objective of this review is to present the current understanding of cervical ripening in terms of molecular regulation and cell signaling.

A decade's experience in primipara, term, singleton, vertex parturients with a sustained low rate of CD

Background Cesarean delivery (CD) in primiparas with a term singleton vertex fetus (PTSV) is a sentinel event for the future mode of delivery and determinant of repeat CD risk. We aimed to evaluate the risk factors for primary CD in a population with a decade of sustained low rate of intrapartum CD. Methods This was a retrospective single-center cohort study between 2005 and 2014. The primary outcome of the study was the mode of delivery. PTSV who attempted vaginal delivery were identified and categorized according to the mode of delivery: vaginal delivery vs. CD. Risk factors for intrapartum CD adjusted odds ratio (aOR) [95% confidence interval (CI)] in multivariate analysis were reported. Results During the study, 121,483 deliveries were registered; 26,301 (21.6%) PTSV were admitted in labor, of which 1944 (7.4%) had an intrapartum CD. Significantly in multivariate analysis, this group had a unique risk profile as compared to those who delivered vaginally; non modifiable risks included advanced maternal age: 3.06 (2.16-4.33), P < 0.001; prior multiple (≥3) miscarriages: 1.94 (1.04-3.62), P = 0.04; low (<6) modified admission cervical score: 2.41 (2.07-2.82), P < 0.001; low birth weight (BW): 1.42 (1.00-2.01), P = 0.05 or macrosomia: 2.38 (1.77-3.21), P < 0.001; modifiable risks included induction of labor: 1.79 (1.51-2.13), P < 0.001 and oxytocin labor augmentation: 8.36 (6.84-10.22), P < 0.001. Conclusion In a population of PTSV with a sustained low risk for intrapartum cesarean maintained by a strict labor management, induction of labor remains a significant and sole potentially modifiable risk factor for CD.

Intrapartum prediction of emergency delivery due to non-reassuring fetal status at 40 weeks' gestation in low-risk pregnancies: contribution of Doppler parameters, maternal history, and intrapartum clinical characteristics

OBJECTIVE

To assess the added value of Doppler parameters, maternal history, and intrapartum clinical characteristics for the prediction of emergency delivery due to non-reassuring fetal status in low-risk pregnancies.

METHODS

This was a prospective cohort of low-risk pregnancies undergoing ultrasound assessment at 40 weeks' gestation within 7 days of delivery. The main outcome was emergency cesarean section due to non-reassuring fetal status. The association between Doppler parameters, intrapartum clinical characteristics, and maternal history was performed by logistic regression. The predictive performance of the constructed models was assessed by receiver operating characteristic (ROC) curve analysis and the area under the curve (AUC).

RESULTS

From 403 included pregnancies, 18.6% (n = 75) underwent an emergency delivery due to non-reassuring fetal status. The mean gestational age at birth was 40.5 (SD 5) days. Middle cerebral artery pulsatility index (MCA) and cerebroplacental ratio (CPR) were lower in the emergency cesarean section group (1.16 versus 1.30; p < .001, and 1.61 versus 1.78; p = .001, respectively). There was a higher incidence of small-for-gestational-age neonates (20 versus 10.1%; p = .017), lower Apgar scores at the 5th minute (9.7 versus 9.9; p = .006), and NICU admissions (9 versus 3%; p = .016) in the emergency cesarean section group. The base model comprised nulliparity, and the finding of meconium-stained amniotic fluid during labor, achieving an AUC of 66%, while the addition of the MCA Z-score significantly improved the previous model (AUC: 73%; DeLong: p = .008).

CONCLUSIONS

In low-risk pregnant woman at term, the addition of MCA Z-score to a previous model comprising maternal history and intrapartum clinical findings, significantly improves the prediction of emergency delivery due to non-reassuring fetal status.

Induction of labor and postpartum blood loss

BACKGROUND

To analyze blood loss after delivery in women with induction of labor compared to women with spontaneous onset of labor.

METHODS

In this secondary analysis of a prospective cohort study investigating postpartum hemorrhage, 965 deliveries were analyzed including 380 women with induction of labor (39%) between 2015 and 2016. Primary outcome parameters were rate of postpartum hemorrhage, estimated blood loss and post-partum decrease in hemoglobin.

RESULTS

Rates of postpartum hemorrhage and estimated blood loss were not significantly different in women with induction of labor. Women with induction of labor had a significantly reduced decrease in hemoglobin after delivery. In the multivariate linear regression analysis, induction of labor remained associated with reduced decrease in hemoglobin. Secondary maternal and neonatal outcomes were unaffected.

CONCLUSIONS

Induction of labor is not associated with increased blood loss after delivery and should not be regarded as a risk factor for postpartum hemorrhage.

Comparing birth experience and birth outcome of vaginal births between induced and spontaneous onset of labour: a prospective study

PURPOSE

In developed countries, around 25% of all births involve labour induction. Studies have indicated that labour induction negatively influences the birth experience as well as the birth process. However, the impact of labour induction when only considering vaginal deliveries has not been studied yet, which was the purpose of the present study.

METHODS

186 women who gave birth vaginally took part in this prospective study. 95 women gave birth after spontaneous onset of labour (SL-group) and 91 women received a labour induction (LI-group). Eight to 72 h after birth, the women filled in the revised version of the standardised Childbirth Experience Questionnaire, which examines the birth experience in four dimensions (Own Capacity, Perceived Safety, Participation and Professional Support). Medical details regarding birth and fetal outcomes were taken from the medical records.

RESULTS

Birth outcomes (the number of epidural anaesthesia, the duration of birth, birth risks and childbirth injuries) as well as fetal outcomes (APGAR after 1 and 5 min and arterial cord pH) did not differ between the groups. Regarding the subjective birth experience, the LI-group indicated significantly lower values for Perceived Safety and Participation compared to the SL-group, while there were no differences for the dimensions Own Capacity and Professional Support.

DISCUSSION

Successful labour induction resulting in a vaginal birth did not negatively influence birth and fetal outcomes and only partly affected the women's birth experience. The negative impact of labour induction on the dimensions Perceived Safety and Participation should sensitize midwives in order to provide optimal support.

Small-for-gestational-age babies after 37 weeks: impact study of risk-stratification protocol

OBJECTIVE

Although no clear evidence exists, many international guidelines advocate early-term delivery of small-for-gestational-age (SGA) fetuses. The aim of this study was to determine whether a risk-stratification protocol in which low-risk SGA fetuses are managed expectantly beyond 37 weeks affects perinatal and maternal outcomes.

METHODS

This was an impact study examining data collected over a 39-month period (1 January 2013 to 30 April 2016) at a tertiary referral unit. The study included women who were referred to the fetal medicine unit with a singleton non-anomalous fetus diagnosed antenatally as SGA (estimated fetal weight < 10^th centile) from 36 + 0 weeks' gestation. In 2014, a protocol for management of SGA was introduced, which included risk stratification with surveillance and expectant management after 37 weeks for lower-risk babies (protocol group). This was compared with the previous strategy, which recommended delivery at around 37 weeks (pre-protocol group). Primary outcome was neonatal composite adverse outcome.

RESULTS

In the pre-protocol group, there were 138 SGA babies; in the protocol group there were 143. Mean gestational ages at delivery were 37.4 weeks in the pre-protocol group and 38.2 weeks in the protocol group (P = 0.04). The incidence of neonatal composite adverse outcome was lower in the protocol group (9% vs 22%; P < 0.01), as was neonatal unit admission (13% vs 39%; P < 0.01). Induction of labor and Cesarean section rates were lower, and vaginal delivery rate (83% vs 60%; P < 0.01) was higher, in the protocol group. Most of the differences were as a result of delayed delivery of SGA babies that were stratified as low risk.

CONCLUSIONS

The findings of this study suggest that protocol-based management of SGA babies may improve outcome, and that identification of moderate SGA should not in isolation prompt delivery. Larger numbers are required to assess any impact on perinatal mortality. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Labor induction and cesarean delivery: A prospective cohort study of first births in Pennsylvania, USA

BACKGROUND

Mode of delivery at first childbirth largely determines mode of delivery at subsequent births, so it is particularly important to understand risk factors for cesarean delivery at first childbirth. In this study, we investigated risk factors for cesarean delivery among nulliparous women, with focus on the association between labor induction and cesarean delivery.

METHODS

A prospective cohort study of 2851 nulliparous women with singleton pregnancies who attempted vaginal delivery at hospitals in Pennsylvania, 2009-2011, was conducted. We used nested logistic regression models and multiple mediational analyses to investigate the role of three groups of variables in explaining the association between labor induction and unplanned cesarean delivery-the confounders of maternal characteristics and indications for induction, and the mediating (intrapartum) factors-including cervical dilatation, labor augmentation, epidural analgesia, dysfunctional labor, dystocia, fetal intolerance of labor, and maternal request of cesarean during labor.

RESULTS

More than a third of the women were induced (34.3%) and 24.8% underwent cesarean delivery. Induced women were more likely to deliver by cesarean (35.9%) than women in spontaneous labor (18.9%), unadjusted OR 2.35 (95% CI 1.97-2.79). The intrapartum factors significantly mediated the association between labor induction and cesarean delivery (explaining 76.7% of this association), particularly cervical dilatation <3 cm at hospital admission, fetal intolerance of labor, and dystocia. The indications for labor induction only explained 6.2%.

CONCLUSIONS

Increased risk of cesarean delivery after labor induction among nulliparous women is attributable mainly to lower cervical dilatation at hospital admission and higher rates of labor complications.

Clinical trials registries are underused in the pregnancy and childbirth literature: a systematic review of the top 20 journals

Background

Systematic reviews and meta-analyses that do not include unpublished data in their analyses may be prone to publication bias, which in some cases has been shown to have deleterious consequences on determining the efficacy of interventions.

Methods

We retrieved systematic reviews and meta-analyses published in the past 8 years (January 1, 2007–December 31, 2015) from the top 20 journals in the Pregnancy and Childbirth literature, as rated by Google Scholar’s h5-index. A meta-epidemiologic analysis was performed to determine the frequency with which authors searched clinical trials registries for unpublished data.

Results

A PubMed search retrieved 372 citations, 297 of which were deemed to be either a systematic review or a meta-analysis and were included for analysis. Twelve (4 %) of these searched at least one WHO-approved clinical trials registry or clinicaltrials.gov.

Conclusion

Systematic reviews and meta-analyses published in pregnancy and childbirth journals do not routinely report searches of clinical trials registries. Including these registries in systematic reviews may be a promising avenue to limit publication bias if registry searches locate unpublished trial data that could be used in the systematic review.