Induction of labour during the COVID-19 pandemic: a national survey of impact on practice in the UK

BACKGROUND

Induction of labour (IOL) is one of the most commonly performed interventions in maternity care, with outpatient cervical ripening increasingly offered as an option for women undergoing IOL. The COVID-19 pandemic has changed the context of practice and the option of returning home for cervical ripening may now assume greater significance. This work aimed to examine whether and how the COVID-19 pandemic has changed practice around IOL in the UK.

METHOD

We used an online questionnaire to survey senior obstetricians and midwives at all 156 UK NHS Trusts and Boards that currently offer maternity services. Responses were analysed to produce descriptive statistics, with free text responses analysed using a conventional content analysis approach.

FINDINGS

Responses were received from 92 of 156 UK Trusts and Boards, a 59% response rate. Many Trusts and Boards reported no change to their IOL practice, however 23% reported change in methods used for cervical ripening; 28% a change in criteria for home cervical ripening; 28% stated that more women were returning home during cervical ripening; and 24% noted changes to women's response to recommendations for IOL. Much of the change was reported as happening in response to attempts to minimise hospital attendance and restrictions on birth partners accompanying women.

CONCLUSIONS

The pandemic has changed practice around induction of labour, although this varied significantly between NHS Trusts and Boards. There is a lack of formal evidence to support decision-making around outpatient cervical ripening: the basis on which changes were implemented and what evidence was used to inform decisions is not clear.

Stillbirth rates, service outcomes and costs of implementing NHS England's Saving Babies' Lives care bundle in maternity units in England: A cohort study

Objective

To assess implementation of the Saving Babies Lives (SBL) Care Bundle, a collection of practice recommendations in four key areas, to reduce stillbirth in England.

Design

A retrospective cohort study of 463,630 births in 19 NHS Trusts in England using routinely collected electronic data supplemented with case note audit (n = 1,658), and surveys of service users (n = 2,085) and health care professionals (n = 1,064). The primary outcome was stillbirth rate. Outcome rates two years before and after the nominal SBL implementation date were derived as a measure of change over the implementation period. Data were collected on secondary outcomes and process outcomes which reflected implementation of the SBL care bundle.

Results

The total stillbirth rate, declined from 4.2 to 3.4 per 1,000 births between the two time points (adjusted Relative Risk (aRR) 0.80, 95% Confidence Interval (95% CI) 0.70 to 0.91, P<0.001). There was a contemporaneous increase in induction of labour (aRR 1.20 (95%CI 1.18–1.21), p<0.001) and emergency Caesarean section (aRR 1.10 (95%CI 1.07–1.12), p<0.001). The number of ultrasound scans performed (aRR 1.25 (95%CI 1.21–1.28), p<0.001) and the proportion of small for gestational age infants detected (aRR 1.59 (95%CI 1.32–1.92), p<0.001) also increased. Organisations reporting higher levels of implementation had improvements in process measures in all elements of the care bundle. An economic analysis estimated the cost of implementing the care bundle at ~£140 per birth. However, neither the costs nor changes in outcomes could be definitively attributed to implementation of the SBL care bundle.

Conclusions

Implementation of the SBL care bundle increased over time in the majority of sites. Implementation was associated with improvements in process outcomes. The reduction in stillbirth rates in participating sites exceeded that reported nationally in the same timeframe. The intervention should be refined to identify women who are most likely to benefit and minimise unwarranted intervention.

Trial registration

The study was registered on (NCT03231007); www.clinicaltrials.gov.

Increased labor induction and women presenting with decreased or altered fetal movements - a population-based survey

Introduction

Women’s awareness of fetal movements is important as perception of decreased fetal movements can be a sign of a compromised fetus. We aimed to study rate of labor induction in relation to number of times women seek care due to decreased or altered fetal movements during their pregnancy compared to women not seeking such care. Further, we investigated the indication of induction.

Material and methods

A prospective population-based cohort study including all obstetric clinics in Stockholm, Sweden. Questionnaires were distributed to women who sought care due to decreased or altered fetal movements ≥ 28 week’s gestation in 2014, women for whom an examination did not indicate a compromised fetus that required induction of labor or cesarean section when they sought care. Women who gave birth at ≥ 28 weeks’ gestation in 2014 in Stockholm comprises the reference group.

Results

Labor was induced more often among the 2683 women who had sought care due to decreased or altered fetal movements (RR 1.4, 95% CI 1.3–1.5). In women who presented with decreased or altered fetal movements induction of labor occurred more frequently for fetal indication than those with induction of labor and no prior fetal movement presentation (RR 1.6, 95% CI 1.4–1.8). The rate of induction increased with number of times a woman sought care, RR 1.3 for single presentation to 3.2 for five or more.

Conclusions

We studied women seeking care for decreased or altered fetal movements and for whom pregnancy was not terminated with induction or caesarean section. Subsequent (median 20 days), induction of labor and induction for fetal indications were more frequent in this group compared to the group of women with no fetal movement presentations. Among women seeking care for altered or decreased fetal movements, the likelihood of induction of labor increased with frequency of presentation.

Perinatal mortality associated with induction of labour versus expectant management in nulliparous women aged 35 years or over: An English national cohort study

BACKGROUND

A recent randomised controlled trial (RCT) demonstrated that induction of labour at 39 weeks of gestational age has no short-term adverse effect on the mother or infant among nulliparous women aged ≥35 years. However, the trial was underpowered to address the effect of routine induction of labour on the risk of perinatal death. We aimed to determine the association between induction of labour at ≥39 weeks and the risk of perinatal mortality among nulliparous women aged ≥35 years.

METHODS AND FINDINGS

We used English Hospital Episode Statistics (HES) data collected between April 2009 and March 2014 to compare perinatal mortality between induction of labour at 39, 40, and 41 weeks of gestation and expectant management (continuation of pregnancy to either spontaneous labour, induction of labour, or caesarean section at a later gestation). Analysis was by multivariable Poisson regression with adjustment for maternal characteristics and pregnancy-related conditions. Among the cohort of 77,327 nulliparous women aged 35 to 50 years delivering a singleton infant, 33.1% had labour induced: these women tended to be older and more likely to have medical complications of pregnancy, and the infants were more likely to be small for gestational age. Induction of labour at 40 weeks (compared with expectant management) was associated with a lower risk of in-hospital perinatal death (0.08% versus 0.26%; adjusted risk ratio [adjRR] 0.33; 95% CI 0.13-0.80, P = 0.015) and meconium aspiration syndrome (0.44% versus 0.86%; adjRR 0.52; 95% CI 0.35-0.78, P = 0.002). Induction at 40 weeks was also associated with a slightly increased risk of instrumental vaginal delivery (adjRR 1.06; 95% CI 1.01-1.11, P = 0.020) and emergency caesarean section (adjRR 1.05; 95% CI 1.01-1.09, P = 0.019). The number needed to treat (NNT) analysis indicated that 562 (95% CI 366-1,210) inductions of labour at 40 weeks would be required to prevent 1 perinatal death. Limitations of the study include the reliance on observational data in which gestational age is recorded in weeks rather than days. There is also the potential for unmeasured confounders and under-recording of induction of labour or perinatal death in the dataset.

CONCLUSIONS

Bringing forward the routine offer of induction of labour from the current recommendation of 41-42 weeks to 40 weeks of gestation in nulliparous women aged ≥35 years may reduce overall rates of perinatal death.

Temporal Trends in Late Preterm and Early Term Birth Rates in 6 High-Income Countries in North America and Europe and Association With Clinician-Initiated Obstetric Interventions

IMPORTANCE

Clinicians have been urged to delay the use of obstetric interventions (eg, labor induction, cesarean delivery) until 39 weeks or later in the absence of maternal or fetal indications for intervention.

OBJECTIVE

To describe recent trends in late preterm and early term birth rates in 6 high-income countries and assess association with use of clinician-initiated obstetric interventions.

DESIGN

Retrospective analysis of singleton live births from 2006 to the latest available year (ranging from 2010 to 2015) in Canada, Denmark, Finland, Norway, Sweden, and the United States.

EXPOSURES

Use of clinician-initiated obstetric intervention (either labor induction or prelabor cesarean delivery) during delivery.

MAIN OUTCOMES AND MEASURES

Annual country-specific late preterm (34-36 weeks) and early term (37-38 weeks) birth rates.

RESULTS

The study population included 2,415,432 Canadian births in 2006-2014 (4.8% late preterm; 25.3% early term); 305,947 Danish births in 2006-2010 (3.6% late preterm; 18.8% early term); 571,937 Finnish births in 2006-2015 (3.3% late preterm; 16.8% early term); 468,954 Norwegian births in 2006-2013 (3.8% late preterm; 17.2% early term); 737,754 Swedish births in 2006-2012 (3.6% late preterm; 18.7% early term); and 25,788,558 US births in 2006-2014 (6.0% late preterm; 26.9% early term). Late preterm birth rates decreased in Norway (3.9% to 3.5%) and the United States (6.8% to 5.7%). Early term birth rates decreased in Norway (17.6% to 16.8%), Sweden (19.4% to 18.5%), and the United States (30.2% to 24.4%). In the United States, early term birth rates decreased from 33.0% in 2006 to 21.1% in 2014 among births with clinician-initiated obstetric intervention, and from 29.7% in 2006 to 27.1% in 2014 among births without clinician-initiated obstetric intervention. Rates of clinician-initiated obstetric intervention increased among late preterm births in Canada (28.0% to 37.9%), Denmark (22.2% to 25.0%), and Finland (25.1% to 38.5%), and among early term births in Denmark (38.4% to 43.8%) and Finland (29.8% to 40.1%).

CONCLUSIONS AND RELEVANCE

Between 2006 and 2014, late preterm and early term birth rates decreased in the United States, and an association was observed between early term birth rates and decreasing clinician-initiated obstetric interventions. Late preterm births also decreased in Norway, and early term births decreased in Norway and Sweden. Clinician-initiated obstetric interventions increased in some countries but no association was found with rates of late preterm or early term birth.

The Feasibility of Tracking Elective Deliveries Prior to 39 Gestational Weeks: Lessons From Three California Projects

The tracking of elective deliveries (ED) prior to 39 gestational weeks has become a mandatory requirement for all hospitals with ≥1,100 deliveries for accreditation by The Joint Commission (TJC); however, the feasibility and accuracy of monitoring efforts remain problematic for many hospitals. Here, we evaluated the feasibility of three operational approaches to tracking ED. We used mixed methods to evaluate the feasibility of 3 different approaches to tracking ED: (1) using administrative data, (2) using electronic medical record (EMR) data, and (3) using targeted data collection in a county-wide quality improvement (QI) effort. For (1), we analyzed data from the California 2009 linked birth cohort dataset, and calculated hospital rates of ED using TJC technical specifications. For (2), we performed a case study of a project that recruited hospitals to provide EMR data for the TJC measure calculation. For (3), we performed a case study of a project that recruited hospitals to prospectively track elective inductions of labor. For (1), hospital discharge data were insufficient without supplementation from the EMR or birth certificate. For (2), legal and operational issues surrounding data sharing, and non-standardized data elements prohibited hospital participation. For (3), the QI approach successfully established policies and data collection systems yet lacked infrastructure to assure sustainability at a hospital or regional level. In summary, ED tracking required the coordination and support of multiple resources to enable hospitals to satisfactorily report on this measure.

Temporal trends in fetal mortality at and beyond term and induction of labor in Germany 2005-2012: data from German routine perinatal monitoring

PURPOSE

While a variety of factors may play a role in fetal and neonatal deaths, postmaturity as a cause of stillbirth remains a topic of debate. It still is unclear, whether induction of labor at a particular gestational age may prevent fetal deaths.

METHODS

A multidisciplinary working group was granted access to the most recent set of relevant German routine perinatal data, comprising all 5,291,011 hospital births from 2005 to 2012. We analyzed correlations in rates of induction of labor (IOL), perinatal mortality (in particular stillbirths) at different gestational ages, and fetal morbidity. Correlations were tested with Pearson's product-moment analysis (α = 5 %). All computations were performed with SPSS version 22.

RESULTS

Induction rates rose significantly from 16.5 to 21.9 % (r = 0.98; p < 0.001). There were no significant changes in stillbirth rates (0.28-0.35 per 100 births; r = 0.045; p = 0.806). Stillbirth rates 2009-2012 remained stable in all gestational age groups irrespective of induction. Fetal morbidity (one or more ICD-10 codes) rose significantly during 2005-2012. This was true for both children with (from 33 to 37 %, r = 0.784, p < 0.001) and without (from 25 to 31 %, (r = 0.920, p < 0.001) IOL.

CONCLUSIONS

An increase in IOL at term is not associated with a decline in perinatal mortality. Perinatal morbidity increased with and without induction of labor.

Recent declines in induction of labor by gestational age

After nearly 20 years of consecutive increases, induction of labor for singleton births reached a high of 23.8% in 2010, then declined in 2011 (23.7%) and 2012 (23.3%). Trends in induction rates vary by gestational age, with rates for most gestational age groups declining since 2010. Induction rates for births at 36, 37, and 38 weeks have declined since 2006, with the largest decrease at 38 weeks. From 2006 through 2012, induction rates at 38 weeks of gestation declined for all maternal age groups under 40 and for each of the largest race and Hispanic origin groups. Induction rates at 38 weeks declined for 36 states and the District of Columbia (DC) from 2006 through 2012, with declines ranging from 5% to 48%; rates for 31 states and DC declined at least 10%. During the 1980s, 1990s, and through 2006, the length of pregnancies in the United States shortened (1). From 1981 through 2006, the proportion of infants born at less than 39 completed weeks of gestation increased nearly 60%, while births at 39 weeks or more declined more than 20%. This shift in the gestational age distribution has been associated with greater use of cesarean delivery and induction of labor prior to full term (2-4). In more recent years, however, the trend towards shorter gestational ages has partially reversed. Since 2006, births delivered at less than 39 weeks have declined (down 12%), and births at 39 weeks or more have increased (up 9%) (1). This report explores trends in induction of labor for singleton births by gestational age, maternal age, race and Hispanic origin, and state for 2006-2012.

Epidemiologic considerations: scope of problem and disparity concerns

Elective labor induction is an increasingly common practice not only in high-income countries but also in many low-income and middle-income countries. Many questions remain unanswered on the safety and cost-effectiveness of elective labor induction, particularly in resource-constrained settings wherein there may be a high unmet need for medically indicated inductions, as well as limited or no access to appropriate medications and equipment for induction and monitoring, comprehensive emergency obstetric care, safe, and timely cesarean section, and appropriate supervision from health professionals. This article considers the global perspective on the epidemiology, practices, safety, and costs associated with elective labor induction.

The perinatal quality collaborative of North Carolina's 39 weeks project: a quality improvement program to decrease elective deliveries before 39 weeks of gestation

BACKGROUND

Despite long-standing guidelines from the American College of Obstetricians and Gynecologists that call for avoiding elective births prior to 39 weeks of gestation, elective deliveries make up almost one-third of US births occurring in weeks 36-38. Poor outcomes are more likely for infants born electively before 39 weeks than for those born at 39 weeks. The Perinatal Quality Collaborative of North Carolina (PQCNC) undertook the 39 Weeks Project in 2009-2010 with the aim of reducing the number of early-term elective deliveries in North Carolina hospitals.

METHODS

Participating hospitals (N = 33) provided retrospective data on all early-term deliveries and created new policies, or amended or enforced existing policies, to accomplish the project's goals. Project activities included in-person learning sessions, regional meetings, webinars, electronic newsletters, a secure extranet Web site where participating hospitals could share relevant materials, and individual leadership consultations with hospital teams. Hospitals submitted monthly data to PQCNC, which provided ongoing training and data analysis.

RESULTS

Elective deliveries before 39 weeks of gestation decreased 45% over the project period, from 2% to 1.1% of all deliveries. The proportion of elective deliveries among all scheduled early-term deliveries also decreased, from 23.63% to 16.19%. There was an increase in the proportion of patients with documented evidence of medical indications for early delivery, from 62.4% to 88.2%.

LIMITATIONS

No data were collected to determine whether outcomes changed for patients whose deliveries were deferred. The project also depended on each hospital to code its own data.

CONCLUSION

The PQCNC's 39 Weeks Project successfully decreased the rate of early-term elective deliveries in participating hospitals.

Hospitals to docs and moms: don't rush the baby

Hospitals are working to reduce early elective deliveries and cut the chance for harm to infants and mothers. Convincing physicians and women can be difficult; some hospitals have gone so far as to implement "hard stops.

Trends in the distribution of gestational age and contribution of planned births in New South Wales, Australia

BACKGROUND

There is concern that the rate of planned births (by pre-labour caesarean section or induction of labour) is increasing and that the gestation at which they are being conducted is decreasing. The aim of this study was to describe trends in the distribution of gestational age, and assess the contribution of planned birth to any such changes.

METHODS

We utilised the New South Wales (NSW) Perinatal Data Collection to undertake a population-based study of all births in NSW, Australia 1994-2009. Trends in gestational age were determined by year, labour onset and plurality of birth.

RESULTS

From 1994-2009, there was a gradual and steady left-shift in overall distribution of gestational age at birth, with a decline in the modal gestational age from 40 to 39 weeks. For singletons, there was a steady but significant reduction in the proportion of spontaneous births. Labour inductions increased in the proportion performed, with a gradual and changing shift in the distribution from a majority at 40 weeks to an increase at both 37-39 weeks and 41 weeks gestation. The proportion of pre-labour caesareans also increased steadily at each gestational age and doubled since 1994, with most performed at 39 weeks in 2009 compared with 38 weeks up to 2001.

CONCLUSIONS

Findings suggest a changing pattern towards births at earlier gestations, fewer births commencing spontaneously and increasing planned births. Factors associated with changing clinical practice and long-term implications on the health and well-being of mothers and babies should be assessed.

Limiting the caesarean section rate in low risk pregnancies is key to lowering the trend of increased abdominal deliveries: an observational study

BACKGROUND

As the rate of Caesarean sections (CS) continues to rise in Western countries, it is important to analyze the reasons for this trend and to unravel the underlying motives to perform CS. This research aims to assess the incidence and trend of CS in a population-based birth register in order to identify patient groups with an increasing risk for CS.

METHODS

Data from the Flemish birth register 'Study Centre for Perinatal Epidemiology' (SPE) were used for this historic control comparison. Caesarean sections (CS) from the year 2000 (N = 10540) were compared with those from the year 2008 (N = 14016). By means of the Robson classification, births by Caesarean section were ordered in 10 groups according to mother - and delivery characteristics.

RESULTS

Over a period of eight years, the CS rise is most prominent in women with previous sections and in nulliparous women with a term cephalic in spontaneous labor. The proportion of inductions of labor decreases in favor of elective CS, while the ongoing inductions of labor more often end in non-elective CS.

CONCLUSIONS

In order to turn back the current CS trend, we should focus on low-risk primiparae. Avoiding unnecessary abdominal deliveries in this group will also have a long-term effect, in that the number of repeat CS will be reduced in the future. For the purpose of self-evaluation, peer discussion on the necessity of CS, as well as accurate registration of the main indication for CS are recommended.

National trends and racial differences in late preterm induction

OBJECTIVE

The objective of the study was to determine the trends and racial differences in late preterm induction (LPI) of labor in the United States.

STUDY DESIGN

Data from the National Vital Statistics System were used to identify women eligible for induction between 34 and 42 weeks' gestation from 1991 to 2006. Annual LPI rates were calculated, and maternal race/ethnicity was classified into 4 groups. Changes in the frequency and odds of LPI, stratified by race/ethnicity, were assessed using logistic regression.

RESULTS

Among the 42.0 million eligible women, LPI rates increased from 0.46% to 1.37% (P < .01) over 16 years. LPI rates were highest for black women (P < .01) each year, and after adjusting for confounding factors, the odds of LPI were highest (P < .01) and rose most rapidly (P < .01) for black women (non-Hispanic white: odds ratio [OR], 1 [referent]; Hispanic white: OR, 0.76; black: OR, 1.31; other: OR, 0.81; P < .01).

CONCLUSION

LPI rates were persistently highest and rose most rapidly for black women.

The influence of obstetric intervention on trends in twin stillbirths: United States, 1989–99

OBJECTIVE

Although twin stillbirth rates have declined substantially over the past two decades, the contribution of changes in obstetric interventions to reducing twin stillbirths has not been quantified.

METHODS

We carried out a retrospective cohort study of twin live births and stillbirths in the United States between 1989 and 1999 (n=1,102,212). Changes in the rate of stillbirth (> or =22 weeks) before and after adjustment for changes in labor induction, Cesarean delivery and sociodemographic factors were estimated through ecological logistic regression analysis. This analysis was based on aggregating data by each state within the United States.

RESULTS

Between 1989 and 1999, rates of labor induction and Cesarean delivery among twin live births increased by 138% (from 5.8% to 13.8%) and 15% (from 48.3% to 55.6%), respectively. These changes were accompanied by a 43% decline in the stillbirth rate between 1989 and 1999 (from 24.4 to 13.9 per 1000 fetuses at risk). After excluding births weighing < 500 g, rates of labor induction among twins at 22-27 weeks', 28-33 weeks' and > or =34 weeks' gestation increased by 95%, 131% and 127%, respectively, between 1989 and 1999. Cesarean delivery rates also increased by 55%, 29% and 2% in these same gestational age categories. The 48% (relative risk (RR) 0.52, 95% confidence interval (CI) 0.49-0.55) decline in stillbirth rate between 1989-91 and 1997-99 was reduced to a 25% (RR 0.75, 95% CI 0.72-0.79) decline after adjustment for changes in labor induction and Cesarean delivery. The decline in the rate of twin stillbirths was larger at later gestational ages (at > or =32 and > or =34 weeks) where the largest absolute increases in labor induction rates were observed.

CONCLUSIONS

The use of Cesarean delivery and especially labor induction for twin pregnancies has increased substantially in the United States over the last decade and these changes have been associated with a large decline in the rate of stillbirth among twins.

Where are the Sunday babies? II. Declining weekend birth rates in Switzerland

Birth dates from almost 3 million babies born between 1969 and 2005 in Switzerland were analyzed for the weekday of birth. As in other countries but with unprecedented amplitude, a very marked non-random distribution was discovered with decreasing numbers of births on weekends, reaching -17.9% in 2005. While most of this weekend births avoidance rate is due to fewer births on Sundays (up to -21.7%), the downward trend is primarily a consequence of decreasing births on Saturdays (up to -14.5%). For 2005, these percentages mean that 3,728 fewer babies are born during weekends than could be expected from equal distribution. Most interestingly and surprisingly, weekend birth-avoiding rates are significantly correlated with birth numbers (r = 0.86), i.e. the lower the birth number per year, the lower the number of weekend births. The increasing avoidance of births during weekends is discussed as being a consequence of increasing numbers of caesarean sections and elective labor induction, which in Switzerland reach 29.2 and 20.5%, respectively, in 2004. This hypothesis is supported by the observation that both primary and secondary caesarean sections are significantly correlated with weekend birth avoidance rates. It is therefore likely that financial aspects of hospitals are a factor determining the avoidance of weekend births by increasing the numbers of caesarean sections.

Trends in obstetric interventions in the Dutch obstetrical care system in the period 1993–2002

OBJECTIVE

To determine trends in induction of labour-, instrumental vaginal delivery- and caesarean section rates in the Netherlands in the period 1993-2002.

STUDY DESIGN

Data derived from The Netherlands Perinatal Registry and Statistics Netherlands were used to calculate annual rates for induction of labour, instrumental vaginal delivery and caesarean section. Regarding caesarean section, rates were also calculated for different subgroups with respect to parity, presentation of the fetus, gestational age and multiple pregnancies. In the subgroup of women with a singleton fetus in vertex presentation between 37 and 42 weeks of gestation instrumental delivery rates were compared for women with induced labours and women in spontaneous labour.

RESULTS

The overall CS rate rose from 8.1 to 13.6%. Proportionally the rise was greatest for breech presentation (+37.7%), multiple gestations (+12.7%) and women delivering between 24 and 28 weeks (+9.5%). However, in absolute numbers the rise was most impressive in the group of women with a singleton fetus in vertex presentation between 37 and 42 weeks of gestation. Rate of induction of labour and instrumental vaginal delivery remained constant (approximately 15% respectively 10% of all deliveries). In nulliparous term women with singletons in vertex presentation the CS rate increased with 8.0% to a rate of 20.7% when labour was induced versus an increase of 3.4% to a rate of 7.5% in spontaneous labour.

CONCLUSION

In absolute numbers the rise in CS was most extensive in the group of women with a singleton fetus in vertex presentation between 37 and 42 weeks of gestation. Induction of labour rates and instrumental vaginal delivery rates remained constant during the past decade.

Secular trends in socio-economic status and the implications for preterm birth

The rate of preterm birth in the developed world has been shown to be increasing, in part attributable to obstetric intervention. It has been suggested that this may be a differential increase between socio-economic groups. We aimed to assess whether the preterm rate in Norway is different in socio-economic groups defined by maternal education, and to determine the extent to which a difference is attributable to a socio-economic differential in obstetrical intervention, in terms of caesarean section or induction of labour. We used data from the Medical Birth Registry of Norway from 1980 to 1998 with preterm rate as the outcome and maternal educational level, marital status and obstetric intervention as exposure variables. In multivariable analyses, adjustment was made for maternal age, year of birth and birth order, and secular trends were assessed according to year of birth. The preterm birth rate was highest in the lowest socio-economic group. An increase of 25.2% in the preterm rate was seen over the observation period. No apparent differential was seen in the increase of the crude preterm rates between socio-economic groups, although in multivariable analyses there was a significant interaction between socio-economic group and time, implying a stronger effect of low education towards the end of the observation period attributable to demographic change. In conclusion, the preterm birth rate increased over time, but was mainly due to an increase in obstetric interventions. No closing of the gap between socio-economic groups was observed.

Where are the Sunday babies? Observations on a marked decline in weekend births in Germany

In 5-year intervals, data from 722,306 individuals born between 1988 and 2003 in North Rhine Westphalia, Germany's largest state, were analyzed for the weekday of birth. In contrast to data from 1900 to 1950 (n=149,267), serving as historical controls, a very marked nonrandom distribution was discovered, with decreasing numbers of births on weekends, especially on Sundays, reaching deviations from the expected distribution of -17.8% in 2003, while births on weekdays are more frequent than expected (Fridays: +8.1% in 2003). The increasing avoidance of births during weekends by elective labor induction on weekdays is discussed as a consequence of practical and increasing financial constraints of hospitals.

Reliability of the Bishop score before labour induction at term

OBJECTIVE

To evaluate the agreement within three pairs of observers regarding the Bishop score and an informal global evaluation of the cervix (favourable/unfavourable).

STUDY DESIGN

We conducted a reliability study of the Bishop score. Three pairs of examiners (A-B, A-C and D-E) performed independently a cervical examination in 156 term pregnant women admitted for labour induction. We calculated the proportion of agreement and the Kappa coefficient.

RESULTS

Perfect agreement between two observers for the Bishop score was found in 44 women (28%). Accepting a difference of one point between the observers, agreement increased to 66%. Weighted Kappa coefficients for the Bishop score were 69, 54 and 35% for each pair of observers. Kappa coefficients for the informal evaluation of the cervix were 64, 45 and 46, respectively.

CONCLUSION

Agreement between two observers evaluating the cervix is fair to substantial. An informal evaluation of the cervix is as reliable as the Bishop score.

Trends in labor induction in the United States: is it true that what goes up must come down?

Three recent studies examined the national trend in labor induction in the United States. All show a doubling in the rate of induction during the 1990s, although vital statistics data show a consistently higher trend than that obtained from national hospital discharge data. Neither data source adequately documents the full range of indications for induction, its timing, hospital staffing considerations, and other factors that may play a role. Although rates of induction of labor may be leveling off, despite a lack of scientific evidence for its widespread use, rates are likely to remain at current levels for the next few years.

Trends and Issues in Labor Induction in the United States: Implications for Clinical Practice

The labor induction rate is at an all-time high in the United States. Although induction of labor is recommended as a therapeutic option only when the benefits of expeditious birth outweigh the risks of continuing the pregnancy, a "psychosocial indication" has become a common rationale for elective induction in the United States. It is unlikely that all women are provided with a complete discussion of the cascade of interventions that frequently accompany labor induction and the risks of cesarean birth. Although at first glance elective labor induction may seem more convenient, an appreciation of the inconvenience of the greater rates of interventions, the longer labor and overall hospital stay, the higher costs, the additional attention required by the primary health care provider when complications occur, and the risk of an adverse outcome for a mother or baby after an elective procedure with subsequent litigation should cause everyone to exercise caution and reevaluate current practice. Professional organizations should take proactive steps to advocate for pregnant women so they are fully aware of the risks and benefits. A public campaign to discourage elective labor induction for nulliparous women is worth serious consideration.

[Current practice and results of labor induction]

INTRODUCTION

The role of labor induction has been gradually increasing in the last decade all over Europe due to the early detection of fetal jeopardy, improvement of neonatal therapy and availability of cervical ripening agents. Success rate of vaginal delivery depends on maternal, fetal condition and cervical status.

PATIENTS

Authors report the outcome of 795 labor inductions during the period from 1996 to 2000 at the Department of Obstetrics and Gynecology at the University of Debrecen, Hungary. Preinduction cervical ripening and induction method was based on Bishop score and clinical situation.

RESULTS

The rate of induced labor was 5.97% out of 13312 consecutive deliveries. The outcome of induction is discussed in details. The caesarean section rate after induction of vaginal delivery was 25% in this high risk group, and 33.3% among the total number of inductions.

CONCLUSIONS

The clinical application of prostaglandins for cervical ripening among high risk pregnant women facilitates the decision of labor induction and provides a favourable rate of vaginal deliveries.

Obstetric intervention, stillbirth, and preterm birth

Despite widespread recognition that preventing preterm birth is the most important perinatal challenge facing industrialized countries, preterm birth has increased steadily in recent years. This article examines the relation between trends in preterm birth, preterm labor induction/cesarean delivery, stillbirth, and infant mortality. The recent rise in preterm birth in the United States and Canada has been mainly due to increases in mild preterm birth (34-36 weeks). Live births at 34 to 36 weeks' gestation have increased largely as a consequence of increases in preterm induction and preterm cesarean delivery among women at high risk for adverse pregnancy outcomes. Increased obstetric intervention at 34 to 36 weeks' gestation appears to have led to larger-than-expected temporal declines in stillbirth rates at this gestation. Infant mortality rates have declined overall and also among live births at 34 to 36 weeks' gestation. Obstetric intervention at preterm gestation, when indicated, can prevent stillbirth and reduce infant morbidity and mortality despite the increasing rates of preterm delivery.

Rising rates of labor induction: present concerns and future strategies

The rate of labor induction nationwide increased gradually from 9.5% to 19.4% between 1990 and 1998. Reasons for this doubling of inductions relate to widespread availability of cervical ripening agents, pressure from patients, conveniences to physicians, and litigious constraints. The increase in medically indicated inductions was slower than the overall increase, suggesting that induction for marginal or elective reasons has risen more rapidly. Data to support or refute the benefits of marginal or elective inductions are limited. Many trials of inductions for marginal indications are either nonexistent or retrospective with small sample sizes, thereby limiting definitive conclusions. Until prospective clinical trials can better validate reasons for the liberal use of labor induction, it would seem prudent to maintain a cautious approach, especially among nulliparous women. Strategies are proposed for developing evidence-based guidelines to reduce the presumed increase in health care costs, risk of cesarean delivery for nulliparas, and overscheduling in labor and delivery.

Trends in labour and birth interventions among low-risk women in New South Wales

OBJECTIVE

To examine recent trends in obstetric intervention rates among women at low-risk of poor pregnancy outcome.

DESIGN

Cross-sectional analytic study

SETTING AND POPULATION

A population of 336,189 women categorised as low-risk of a poor pregnancy outcome who gave birth to a live singleton in NSW from 1 January 1990 to 31 December 1997.

MAIN OUTCOME MEASURES

Obstetric intervention rates including oxytocin induction and augmentation of labour, epidural analgesia, instrumental births, caesarean section and episiotomy

METHODS

Trends over time were assessed by fitting trend-lines to numbers of births or by trends in proportions. Unconditional logistic regression was used to assess the impact of epidural analgesia on instrumental birth over time.

RESULTS

Rates of operative births did not rise despite increases in maternal age and use of epidural analgesia. Instrumental births declined over time from 26% to 22% among primiparas and 5% to 4% among multiparas. There was also a shift to vacuum extraction rather than forceps. Although instrumental birth was strongly associated with epidural analgesia, the strength of the association declined over the study period, for primiparas from an adjusted odds ratio of 7.2 to 5.2 and for multiparas from 13.2 to 10.3.

CONCLUSIONS

Increased use of epidural analgesia for labour has been a feature of the management of birth at term during the 1990s. The decline in the strength of association between epidural analgesia and instrumental birth may reflect improved epidural techniques and management of epidural labour, and recognition of the adverse maternal outcomes associated with forceps and vacuum births.

[New developments in labor induction]

INTRODUCTION

Misoprostol is a prostaglandin E1 analogue. During the last 8 years it has been examined in clinical trials in obstetrics for the induction of labor and cervical ripening.

AIM

To review the current literature concerning its efficacy, safety and dosage for induction of labor.

MATERIALS AND METHODS

This review is based on the results of 33 articles published during the years 1993-2001. Data was gathered by searching the internet at Pubmed, Medline and the list of references in the relevant articles.

RESULTS

Misoprostol is a highly effective medication for the induction of labor in comparison to prostaglandin E1 or oxytocin. It is stable for years and the cost of treatment is low. Its disadvantage is based on its tendency to evoke increased uterine activity such as tachysystole and hyperstimulation and the fear of uterine rupture. These disadvantages can be overcome by safety measures such as decreasing the dose, increasing time intervals between doses and careful selection of patients.

CONCLUSIONS

Misoprostol is an important and efficient medication in obstetrics for cervical ripening and induction of labor. Therefore, we believe it is appropriate to start clinical trials in Israel too.

U.S. national trends in labor induction, 1989-1998

OBJECTIVE

To examine the epidemiology of labor induction in the United States.

STUDY DESIGN

We used U.S. natality data from 1989 to 1998 and examined the rate of labor induction by year, geographic region, maternal characteristics and pregnancy complications.

RESULTS

Between 1990 and 1998, the rate of labor induction increased from 9.5% to 19.4% of all births nationwide. However, the induction rate varied widely by state. White race, higher education and early initiation of prenatal care were associated with a higher rate of induction. For all gestational ages, a significantly increased induction rate occurred during the study period. The increase for clinically indicated induction was significantly slower than the overall increase, suggesting that elective induction has risen much more rapidly.

CONCLUSION

The rate of induction of labor more than doubled in the U.S. nationwide in the decade from 1989 to 1998. The increased use of labor induction may be attributable to both clinically indicated and elective induction.

Recent trends in fetal and infant outcomes following post-term pregnancies

All births and infant deaths in 1985 87 and 1992 94 in Canada, except in Ontario and Newfoundland, were analyzed to assess the potential impact of the recent increased use of elective labour induction for post-term pregnancies. Probabilistic linkage was carried out of infant death records (Canadian Mortality Database) and respective birth registrations (Canadian Birth Database) for the periods 1985 87 and 1992 94. The combined fetal and infant mortality declined by 20 30% between 1985 87 and 1992 94 at each gestational week beginning at 37 weeks, with no increased reduction among post-term pregnancies. Asphyxia-related fetal and infant deaths, the most likely cause of death being preventable by labour induction for post-term pregnancies, did not decrease among post-term pregnancies. In contrary, a substantial decrease of asphyxia-related deaths was observed at 37 and 38 weeks over the same periods of time. Because fetal and infant deaths are rare events and because the number of pregnancies passing 42 weeks of gestation decreased dramatically during 1992 94, statistically unstable results may be inevitable in the comparison of mortality in this group of pregnancies.

Temporal changes in rates and reasons for medical induction of term labor, 1980-1996

OBJECTIVE

This study was undertaken to assess temporal changes in rates and reasons for medical induction of term labor.

STUDY DESIGN

A retrospective medical record review was conducted on a population-based cohort of 1293 women with term deliveries.

RESULTS

The rate of medical labor induction increased from 12.9% in 1980 to 25.8% in 1995. Stated indications also changed, with a 2-fold increase in induction for postdate gestation, a 23-fold increase in induction for macrosomia, a 15-fold increase in elective induction, and a 22-fold decline in induction for premature rupture of membranes. The average gestational age at delivery of postdate pregnancies declined from 41.9 weeks in 1980 to 41.0 weeks in 1995. By 1995, the average maternal length of stay and the percentage of cesarean deliveries were higher among women with induced labor at term than among those with spontaneous labor at term.

CONCLUSION

Induction of term labor has almost doubled in prevalence during the past 15 years. The most common indications are elective induction and postdate pregnancy, often applied to gestations of 40 to 41 weeks' duration.

Trends in births at and beyond term: evidence of a change?

OBJECTIVE

To examine trends in the distribution of births at and beyond term in New South Wales and in particular, to determine whether any changes are associated with changes in the obstetric practices of induction and elective caesarean section.

DESIGN

Cross-sectional analytic study.

SETTING

New South Wales, Australia.

POPULATION

All 540,162 women delivering a singleton cephalic-presenting infant of gestational age > or = 37 weeks from 1 January 1990 to 31 December 1996.

METHODS

Data were obtained from the New South Wales midwives data collection, a population-based surveillance system covering all births in New South Wales. The data were analysed to examine changes over time and associations between gestational age, maternal factors and onset of labour.

MAIN OUTCOME MEASURES

Induction of labour and elective caesarean section rates.

RESULTS

From 1990 to 1996 there was a significant decrease in births reported as 40 weeks of gestation, from 35,670 (46.3%) to 30,651 (40.3%). These declines were offset by significant increases in births at 38 and 39 weeks. Births > or = 42 weeks declined from 3321 (4.6%) to 2132 (2.8%). The decline in prolonged pregnancies was associated with increasing induction rates at 41 weeks. The re-distribution of some births from 40 to 38-39 weeks was associated with increasing rates of elective caesarean sections and induction at 38 and 39 weeks, and increasing maternal age.

CONCLUSIONS

Clinicians appear to be implementing the recommendations of randomised controlled trials to offer induction after 41 weeks of gestation. However the trend of performing elective caesarean sections at earlier gestational ages may be unnecessarily putting some infants at increased risk of respiratory morbidity.

[National survey on the use of induced labor by obstetricians. Study Group on Induced Labor]

INTRODUCTION

A strong rise in the use of induced labor has been observed in France. The aim of this work was to analyze the different methods used for achieving induction of labor and their implications.

METHODS

One out of four French obstetricians were randomly selected to answer a questionnaire on their practice for achieving induction of labor. Four hundred of the 997 obstetricians answered the questionnaire. Univariate and multivariate analysis was applied.

RESULTS

A high rate of induced labor was correlated with some areas of the country and with private practice. Certain methods were used in spite of opposing advice by experts in the field: elective induction of labor with unfavorable cervix, use of prostaglandins in elective induction of labor, induction of labor in cases of scarred uterus or breech presentation, use of misoprostol. Some methods were still used in spite of their poor efficacy: intravenous oxytocin used with unfavorable cervix, use of intravensou PGE2.

CONCLUSION

This study would show that theory and practice are often distinctly different. Induction of labor is currently used on a far wider scale than ever before. We obviously need studies for careful assessment of the circumstances in which induction of labor is used in order to improve methods and indications of such a clinical practice.

Breast stimulation to augment labor: history, mystery, and culture

This paper describes the development of a researchable project, arising from the clinical observation of a physiologic phenomenon during labor. Augmentation of labor by breast stimulation has been used in a variety of cultures for centuries. The process of developing a clinical study of augmentation in the modern obstetric environment is discussed, with reference to cultural attitudes of patients and health care workers.

Fetal growth retardation: a limit for the further reduction of preterm births

Fetal growth retardation is at present the major obstacle for further reduction in preterm births. After 25 years of continuous decline in the preterm birth rate in France from 6.9% in 1972 to 4.4% in 1981 and 3.8% in 1989, there has been an increase to 4.5% in 1995. The major new fact is the progressive increase of medically induced preterm births, mostly related to fetal growth retardation. Spontaneous preterm births have continued to decrease throughout all these years.