Variation in induction of labour rates across Irish hospitals; a cross-sectional study

Variation in day surgery rates across Irish public hospitals

The appropriate use of day surgery has been shown to provide the same or better outcomes for patients and to increase hospital efficiency. However, it is often underutilised, and rates can vary widely across hospitals. This study examines variation in day-surgery rates across Irish public hospitals and identifies the characteristics associated with these variations. Using patient-level administrative data on high-volume elective procedures, three-level logistic regression models are estimated which allow us to attribute variation in day-surgery rates to hospitals and surgical-teams. We find that day-surgery rates have increased in the last decade and vary substantially between hospitals for most procedures examined. Focusing on laparoscopic cholecystectomy, a key procedure targeted by policymakers, rates varied from 0% to over 90% across hospitals in 2019. We find that a substantial amount of variation in likelihood of day surgery is attributable to the surgical team (56.8%) with 37.8% attributable to the hospital. While there has undoubtedly been progress in the use of day surgery in Ireland there is still scope for improvement. A policy focus on encouraging and incentivising surgical team adoption of day surgery may be warranted, in addition to dedicated resources, and monitoring of day-surgery rate variation across hospitals.

Outpatient cervical ripening and labor induction with low-dose vaginal misoprostol reduces the interval to delivery: a systematic review and network meta-analysis

OBJECTIVE

Several systematic reviews and meta-analyses have summarized the evidence on the efficacy and safety of various outpatient cervical ripening methods. However, the method with the highest efficacy and safety profile has not been determined conclusively. We performed a systematic review and network meta-analysis of published randomized controlled trials to assess the efficacy and safety of cervical ripening methods currently employed in the outpatient setting.

DATA SOURCES

With the assistance of an experienced medical librarian, we performed a systematic search of the literature using MEDLINE, Embase, Scopus, Web of Science, Cochrane Library, and ClinicalTrials.gov. We systematically searched electronic databases from inception to January 14, 2020.

STUDY ELIGIBILITY CRITERIA

We considered randomized controlled trials comparing a variety of methods for outpatient cervical ripening.

METHODS

We conducted a frequentist random effects network meta-analysis employing data from randomized controlled trials. We performed a direct, pairwise meta-analysis to compare the efficacy of various outpatient cervical ripening methods, including placebo. We employed ranking strategies to determine the most efficacious method using the surface under the cumulative ranking curve; a higher surface under the cumulative ranking curve value implied a more efficacious method. We assessed the following outcomes: time from intervention to delivery, cesarean delivery rates, changes in the Bishop score, need for additional ripening methods, incidence of Apgar scores <7 at 5 minutes, and uterine hyperstimulation.

RESULTS

We included data from 42 randomized controlled trials including 6093 participants. When assessing the efficacy of all methods, 25 μg vaginal misoprostol was the most efficacious in reducing the time from intervention to delivery (surface under the cumulative ranking curve of 1.0) without increasing the odds of cesarean delivery, the need for additional ripening methods, the incidence of a low Apgar score, or uterine hyperstimulation. Acupressure (surface under the cumulative ranking curve of 0.3) and primrose oil (surface under the cumulative ranking curve of 0.2) were the least effective methods in reducing the time to delivery interval. Among effective methods, 50 mg oral mifepristone was associated with the lowest odds of cesarean delivery (surface under the cumulative ranking curve of 0.9).

CONCLUSION

When balancing efficacy and safety, vaginal misoprostol 25 μg represents the best method for outpatient cervical ripening.

Single-balloon catheter with concomitant vaginal misoprostol is the most effective strategy for labor induction: a meta-review with network meta-analysis

OBJECTIVE

Several systematic reviews and meta-analyses have been conducted to summarize the evidence for the efficacy of various labor induction agents. However, the most effective agents or strategies have not been conclusively determined. We aimed to perform a meta-review and network meta-analysis of published systematic reviews to determine the efficacy and safety of currently employed pharmacologic, mechanical, and combined methods of labor induction.

DATA SOURCES

With the assistance of an experienced medical librarian, we performed a systematic search of the literature using PubMed, EMBASE, and the Cochrane Central Register of Control Trials. We systematically searched electronic databases from inception to May 31, 2021.

STUDY ELIGIBILITY CRITERIA

We considered systematic reviews and meta-analyses of randomized controlled trials comparing different agents or methods for inpatient labor induction.

METHODS

We conducted a frequentist random-effects network meta-analysis employing data from randomized controlled trials of published systematic reviews. We performed direct pairwise meta-analyses to compare the efficacy of the various labor induction agents and placebo or no treatment. We performed ranking to determine the best treatment using the surface under the cumulative ranking curve. The main outcomes assessed were cesarean delivery, vaginal delivery within 24 hours, operative vaginal delivery, hyperstimulation, neonatal intensive care unit admissions, and Apgar scores of <7 at 5 minutes of birth.

RESULTS

We included 11 systematic reviews and extracted data from 207 randomized controlled trials with a total of 40,854 participants. When assessing the efficacy of all agents and methods, the combination of a single-balloon catheter with misoprostol was the most effective in reducing the odds of cesarean delivery and vaginal birth >24 hours (surface under the cumulative ranking curve of 0.9 for each). Among the pharmacologic agents, low-dose vaginal misoprostol was the most effective in reducing the odds of cesarean delivery, whereas high-dose vaginal misoprostol was the most effective in achieving vaginal delivery within 24 hours (surface under the cumulative ranking curve of 0.9 for each). Single-balloon catheter (surface under the cumulative ranking curve of 0.8) and double-balloon catheter (surface under the cumulative ranking curve of 0.9) were the most effective in reducing the odds of operative vaginal delivery and hyperstimulation. Buccal or sublingual misoprostol (surface under the cumulative ranking curve of 0.9) and the combination of single-balloon catheter and misoprostol (surface under the cumulative ranking curve of 0.9) most effectively reduced the odds of abnormal Apgar scores and neonatal intensive care unit admissions.

CONCLUSION

The combination of a single-balloon catheter with misoprostol was the most effective method in reducing the odds for cesarean delivery and prolonged time to vaginal delivery. This method was associated with a reduction in admissions to the neonatal intensive care unit.

Outpatient versus inpatient cervical ripening with a slow-release dinoprostone vaginal insert in term pregnancies on maternal, neonatal, and birth outcomes: A systematic review

BACKGROUNDS

Outpatient induction of labor (IOL) is an alternative choice offered to pregnant women requiring cervical ripening. Outpatient IOL can provide solutions in terms of women empowerment, but most importantly promotes as normal labor as possible, within the medical context of the IOL. The objectives of this systematic review were to assess safety and effectiveness of cervical ripening performed with a slow-release dinoprostone vaginal insert in term pregnancies in two settings: the outpatient (home) versus the inpatient (hospital).

METHODS

The electronic databases Cinahl, Embase, Medline and Maternity and Infant Care were searched to detect studies that met the inclusion criteria. Both reviewers collected the data and assessed the quality of the studies and assessed the pooled odds ratio using a 95% confidence interval and a random-effects model. Primary outcomes were linked to maternal and neonatal morbidity. Secondary outcomes were related to birth outcomes.

RESULTS

No statistical difference was seen between the outpatient and inpatient setting in terms of maternal complications, neonatal morbidity, cesarean section, and labor onset <24 h. Women in the outpatient setting were significantly less likely to experience uterine hyperstimulation, and they were also significantly more likely to require oxytocin to augment or induce their labor than the women in the inpatient setting. Women in the outpatient setting were more satisfied with the cervical ripening experience.

CONCLUSIONS

Cervical ripening with a slow-release dinoprostone vaginal insert in term pregnancies in the outpatient setting appears as safe as the inpatient setting in terms of maternal, neonatal, and birth outcomes.

Labour induction in twin pregnancies

Medically-indicated deliveries are common in twin pregnancies given the increased risk of various obstetric complications in twin compared to singleton pregnancies, mainly hypertensive disorders of pregnancy and foetal growth restriction. Due to the unique characteristics of twin pregnancies, the success rates and safety of labour induction may be different than in singleton pregnancies. However, while there are abundant data regarding induction of labour in singleton pregnancies, the efficacy and safety of labour induction in twin pregnancies have been far less studied. In the current manuscript we summarize available data on various aspects of labour induction in twin pregnancies including incidence, success rate, prognostic factors, safety and methods for labour induction in twins. This information may assist healthcare providers in counselling patients with twin pregnancies when labour induction is indicated.

Exploring variation in the performance of planned birth: A mixed method study

OBJECTIVE

Variation in practice in relation to indications and timing for both induction of labour (IOL) and planned caesarean section (CS) clearly exists. However, the extent of this variation, and how this variation is explained by clinicians remains unclear. The aim of this study was to map the variation in IOL and planned CS at eight Australian hospitals, and understand why variation occurs from the perspective of clinicians at these hospitals. Our ultimate aim was to identify opportunities for improvement as evidenced by hospital data, clinician experiences, and feedback.

DESIGN

A two-phased mixed method study using sequential explanatory study design. The first phase consisted of an analysis of routinely collected patient data to map variation between hospitals. The second phase consisted of focus groups with clinicians to gain their perspectives on the reasons for variation.

SETTING AND PARTICIPANTS

Patient data consisted of routine data from 19,073 women giving birth at eight Sydney hospitals between November 2017 and October 2018. Focus groups were attended by a total of 61 medical staff and 121 midwives.

RESULTS

Hospital data analysis found substantial variation, before and after adjustment for case-mix, in rates of both IOL (adjusted rates 27.6%-42%) and planned CS (adjusted rate 15.4%-22.6%). Planned CS by gestation also showed variation, although after restricting analysis to term (≥37 weeks gestation) births, variation was reduced. At focus groups, five main themes explaining variation emerged: local guidelines, policies and procedures (inconsistency and ambiguity); uncertainty of the evidence/what is best practice (contradictory research and different interpretations of evidence); clinician preferences, beliefs and values; the culture of the unit; and organisational influences (access to specialised clinics, theatre time).

KEY CONCLUSIONS

Considerable variation in IOL and planned CS, even after case-mix adjustment, was found in this sample of Australian hospitals. Engagement with hospital clinicians identified likely sources of this variation and enabled clinicians at each hospital to consider appropriate local responses to address variation, such as more detailed review of their planned birth cases.

IMPLICATIONS FOR PRACTICE

At a macro level, measures to reduce unwarranted variation should initially focus on consistent national guidelines, while supporting equitable access to operating theatres for optimal CS timing, and shared decision-making training to reduce influence of clinician preference.

Socioeconomic inequalities and adverse pregnancy outcomes in the UK and Republic of Ireland: a systematic review and meta-analysis

OBJECTIVE

There has been an unprecedented rise in infant mortality associated with deprivation in recent years in the United Kingdom (UK) and Republic of Ireland. A healthy pregnancy can have significant impacts on the life chances of children. The objective of this review was to understand the association between individual-level and household-level measures of socioeconomic status and adverse pregnancy outcomes.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Nine databases were searched (Medline, Embase, Scopus, ASSIA, CINAHL, PsycINFO, BNI, MIDRIS and Google Scholar) for articles published between 1999 and August 2019. Grey literature searches were also assessed.

STUDY SELECTION CRITERIA

Studies reporting associations between individual-level or household socioeconomic factors on pregnancy outcomes in the UK or Ireland.

RESULTS

Among the 82 353 search results, 53 821 titles were identified and 35 unique studies met the eligibility criteria. Outcomes reported were neonatal, perinatal and maternal mortality, preterm birth, birth weight and mode of delivery. Pooled effect sizes were calculated using random-effects meta-analysis. There were significantly increased odds of women from lower levels of occupation/social classes compared with the highest level having stillbirth (OR 1.40, 95% CI 1.23 to 1.59, I²98.62%), neonatal mortality (OR 1.39, 95% CI 1.22 to 1.57, I²97.09%), perinatal mortality (OR 1.39, 95% CI 1.23 to 1.57, I²98.69%), preterm birth (OR 1.41, 95% CI 1.33 to 1.50, I²70.97%) and low birth weight (OR 1.40, 95% CI 1.19 to 1.61, I²99.85%). Limitations relate to available data, unmeasured confounders and the small number of studies for some outcomes.

CONCLUSIONS

This review identified consistent evidence that lower occupational status, especially manual occupations and unemployment, were significantly associated with increased risk of multiple adverse pregnancy outcomes. Strategies to improve pregnancy outcomes should incorporate approaches that address wider determinants of health to provide women and families with the best chances of having a healthy pregnancy and baby and to decrease pregnancy-related health inequalities in the general population.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD42019140893.

Evaluation of maternal and perinatal outcomes in pregnancy with high BMI

BACKGROUND

Maternal obesity is a significant risk factor for unfavourable outcomes during pregnancy. However, the extent of this relationship is poorly defined in Irish mothers.

AIMS

This study was to compare maternal and perinatal outcomes between obese and non-obese mothers in an Irish population.

METHODS

A retrospective comparative study was conducted in a secondary level maternity unit for births recorded between January 2018 and January 2019 and 2,793 women were included. BMI calculated at booking visit was used to compare obese (BMI ≥ 30 kg/m²) and non-obese mothers (BMI < 30 kg/m²).

RESULTS

Of 2,793 women included in this study, 2111 had a BMI < 30 kg/m² and 682 had a BMI ≥ 30 kg/m². Obese women were less likely to experience spontaneous onset of labour (33.4% vs. 48.1%, p < 0.001) and more likely to be induced (37.2% vs. 31.0%, p = 0.002). Obesity was associated with a statistically significant increase in stillbirth, fetal macrosomia and emergency caesarean birth rates, whereas operative vaginal deliveries were significantly decreased. Miscarriage, shoulder dystocia, post-partum haemorrhage and spontaneous vaginal deliveries were reduced while elective caesarean birth and low birth weight incidence were increased in obese mothers; however, these results were not statistically significant.

CONCLUSIONS

This study highlights the magnitude of obstetric risks that are associated with maternal obesity within Irish population. Implementation of effective intervention strategies to reduce the number of obese women in pregnancy may have beneficial effects on pregnancy outcomes in Ireland.

Discrimination by parity is a prerequisite for assessing induction of labour outcome - cross-sectional study

Background

To demonstrate that studies on induction of labour should be analyzed by parity as there is a significant difference in the labour outcome among induced nulliparous and multiparous women.

Methods

Obstetric outcome, specifically caesarean section rates, among induced term nulliparous and multiparous women without a previous caesarean section were analyzed in this cross-sectional study using the Robson 10 group classification for the year 2016.

Results

In the total number of 8851 women delivered in 2016, the caesarean section rates among nulliparous women in spontaneous and induced labour, Robson groups 1 and 2A, were 7.84% (151/1925) and 32.63% (437/1339) respectively and among multiparous (excluding those women with a previous caesarean section), Robson group 3 and 4A were 1%(24/2389) and 4.37% (44/1005), respectively. Pre labour caesarean rates for nulliparous and multiparous women, Robson groups 2B and 4B (Robson M, Fetal Matern Med Rev, 12; 23–39, 2001) were 3.91% (133/3397) and 2.86% (100/3494), of the respective single cephalic cohort at term.

Conclusion

The data suggests that studies on induction of labour should be analyzed by parity as there is a significant difference between nulliparous and multiparous women.

The impact of revised diagnostic criteria on hospital trends in gestational diabetes mellitus rates in a high income country

Objective

In 2010, national guidelines were published in Ireland recommending more sensitive criteria for the diagnosis of Gestational Diabetes Mellitus (GDM). The criteria were based on the 2008 Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) Study and were endorsed subsequently by the World Health Organization (WHO). Screening nationally is selective based on risk factors. We examined the impact of the new criteria on hospital trends nationally for GDM over the 10 years 2008–17.

Research design and methods

Data from three national databases, the Hospital Inpatient Enquiry System (HIPE), National Perinatal Reporting System (NPRS) and the Irish Maternity Indicator System (IMIS), were analyzed using descriptive statistics, analysis of variance, and Poisson loglinear modelling.

Results

The overall incidence of GDM nationally increased almost five-fold from 3.1% in 2008 to 14.8% in 2017 (p ≤ 0.001). The incidence varied widely across maternity units. In 2008, the incidence varied from 0.4 to 5.9% and in 2017 it varied from 1.9 to 29.4%. There were increased obstetric interventions among women with GDM over the decade, specifically women with GDM having increased cesarean sections (CS) and induction of labor (IOL) (p ≤ 0.001). These trends were significant in large and mid-sized maternity hospitals (p ≤ 0.001). The increase in GDM diagnosis could not be explained by an increase in maternal age nationally over the decade. The data did not include information on other risk factors such as obesity. The increased incidence in GDM diagnosis was accompanied by a decrease in high birthweight ≥ 4.5 kg nationally.

Conclusions

We found adoption of the new criteria for diagnosis of GDM resulted in a major increase in the incidence of GDM rates. Inter-hospital variations increased over the decade, which may be explained by variations in the implementation of the new national guidelines in different maternity units. It is likely to escalate further as compliance with national guidelines improves at all maternity hospitals, with implications for provision and configuration of maternity services. We observed trends that may indicate improvements for women and their offspring, but more research is required to understand patterns of guideline implementation across hospitals and to demonstrate how increased GDM diagnosis will improve clinical outcomes.

How much synthetic oxytocin is infused during labour? A review and analysis of regimens used in 12 countries

Objective

To compare synthetic oxytocin infusion regimens used during labour, calculate the International Units (IU) escalation rate and total amount of IU infused over eight hours.

Design

Observational study

Setting

Twelve countries, eleven European and South Africa.

Sample

National, regional or institutional-level regimens on oxytocin for induction and augmentation labour

Methods

Data on oxytocin IU dose, infusion fluid amount, start dose, escalation rate and maximum dose were collected. Values for each regimen were converted to IU in 1000ml diluent. One IU corresponded to 1.67μg for doses provided in grams/micrograms. IU hourly dose increase rates were based on escalation frequency. Cumulative doses and total IU amount infused were calculated by adding the dose administered for each previous hour. Main Outcome Measures Oxytocin IU dose infused

Results

Data were obtained on 21 regimens used in 12 countries. Details on the start dose, escalation interval, escalation rate and maximum dose infused were available from 16 regimens. Starting rates varied from 0.06 IU/hour to 0.90 IU/hour, and the maximum dose rate varied from 0.90 IU/hour to 3.60 IU/hour. The total amount of IU oxytocin infused, estimated over eight hours, ranged from 2.38 IU to 27.00 IU, a variation of 24.62 IU and an 11-fold difference.

Conclusion

Current variations in oxytocin regimens for induction and augmentation of labour are inexplicable. It is crucial that the appropriate minimum infusion regimen is administered because synthetic oxytocin is a potentially harmful medication with serious consequences for women and babies when inappropriately used. Estimating the total amount of oxytocin IU received by labouring women, alongside the institution’s mode of birth and neonatal outcomes, may deepen our understanding and be the way forward to identifying the optimal infusion regimen.

Prediction of cesarean delivery in the term nulliparous woman: results from the prospective, multicenter Genesis study

BACKGROUND

In contemporary practice many nulliparous women require intervention during childbirth such as operative vaginal delivery or cesarean delivery (CD). Despite the knowledge that the increasing rate of CD is associated with increasing maternal age, obesity and larger infant birthweight, we lack a reliable method to predict the requirement for such potentially hazardous obstetric procedures during labor and delivery. This issue is important, as there are greater rates of morbidity and mortality associated with unplanned CD performed in labor compared with scheduled CDs. A prediction algorithm to identify women at risk of an unplanned CD could help reduced labor associated morbidity.

OBJECTIVE

In this primary analysis of the Genesis study, our objective was to prospectively assess the use of prenatally determined, maternal and fetal, anthropomorphic, clinical, and ultrasound features to develop a predictive tool for unplanned CD in the term nulliparous woman, before the onset of labor.

MATERIALS AND METHODS

The Genesis study recruited 2336 nulliparous women with a vertex presentation between 39+0 and 40+6 weeks' gestation in a prospective multicenter national study to examine predictors of CD. At recruitment, a detailed clinical evaluation and ultrasound assessment were performed. To reduce bias from knowledge of these data potentially influencing mode of delivery, women, midwives, and obstetricians were blinded to the ultrasound data. All hypothetical prenatal risk factors for unplanned CD were assessed as a composite. Multiple logistic regression analysis and mathematical modeling was used to develop a risk evaluation tool for CD in nulliparous women. Continuous predictors were standardized using z scores.

RESULTS

From a total enrolled cohort of 2336 nulliparous participants, 491 (21%) had an unplanned CD. Five parameters were determined to be the best combined predictors of CD. These were advancing maternal age (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.09 to 1.34), shorter maternal height (OR, 1.72; 95% CI, 1.52 to 1.93), increasing body mass index (OR, 1.29; 95% CI, 1.17 to 1.43), larger fetal abdominal circumference (OR, 1.23; 95% CI, 1.1 to 1.38), and larger fetal head circumference (OR, 1.27; 95% CI, 1.14 to 1.42). A nomogram was developed to provide an individualized risk assessment to predict CD in clinical practice, with excellent calibration and discriminative ability (Kolmogorov-Smirnov, D statistic, 0.29; 95% CI, 0.28 to 0.30) with a misclassification rate of 0.21 (95% CI, 0.19 to 0.25).

CONCLUSION

Five parameters (maternal age, body mass index, height, fetal abdominal circumference, and fetal head circumference) can, in combination, be used to better determine the overall risk of CD in nulliparous women at term. A risk score can be used to inform women of their individualized probability of CD. This risk tool may be useful for reassuring most women regarding their likely success at achieving an uncomplicated vaginal delivery as well as selecting those patients with such a high risk for CD that they should avoid a trial of labor. Such a risk tool has the potential to greatly improve planning hospital service needs and minimizing patient risk.