Obstetric interventions, trends, and drivers of change: A 20-year population-based study from Iceland

Normal birth rates before and after the merging of mixed-risk and low-risk maternity wards in Iceland: A retrospective cohort study on the impact of inter-professional preventative measures

BACKGROUND

In 2014, the National University Hospital of Iceland (NUHI) merged a mixed-risk birth unit and a midwifery-led low-risk unit into one mixed-risk unit. Interprofessional preventative and mitigating measures were implemented since there was a known threat of cultural contamination between mixed-risk and low-risk birth environments. The aim of the study was to assess whether the NUHI's goal of protecting the rates of birth without intervention had been achieved and to support further development of labor services.

METHODS

A retrospective cohort study of all women who had singleton births at NUHI birth units in two 2-year periods, 2012-2013 and 2015-2016. The primary outcome variables, birth without intervention, with or without artificial rupture of membranes (AROM), were adjusted for confounding variables using logistic regression analysis. Secondary outcome variables (individual interventions and maternal and neonatal complications) were analyzed using descriptive statistics, t test, and Chi-square test.

RESULTS

The rate of births without interventions, both with and without AROM, increased significantly after the unit merger and accompanying preventative measures. The rates of AROM, oxytocin augmentation, episiotomies, and epidural analgesia decreased significantly. The rate of induction increased significantly. There were no significant differences in maternal or neonatal complication rates.

CONCLUSIONS

Interprofessional preventative measures, implemented alongside a mixed-risk and low-risk birth unit merger, can increase rates of births without interventions in a mixed-risk hospital setting. However, it is necessary to maintain awareness of the possible effects of a mixed-risk birth environment on the use of childbirth interventions and examine the long-term effects of preventative measures.

Twin birth rates and obstetric interventions in Iceland: A nationwide study from 1997 to 2018

OBJECTIVE

Twin pregnancies are associated with increased antepartum and intrapartum risks. Limited multiple embryo transfers are associated with decreased twin birth rates. We aimed to study the effect of 2009 Icelandic regulations on twin birth rates and examine obstetric intervention rates for twin births during the study period.

METHODS

The study included all births (N = 94 028) in Iceland during 1997-2018. Twin birth rates and obstetric intervention rates were compared over birth year periods using modified Poisson regression adjusted for confounders.

RESULTS

An observed decrease in the twin birth rate trend was most notable from 2006 until 2009. Twin birth decreased in 2009-2013 (prevalence ratio [PR] 0.74, 95% confidence interval [CI] 0.64-0.86) and in 2014-2018 (PR 0.74, 95% CI 0.64-0.86) compared with 1997-2002. This decrease was only evident for women aged 30+ years in stratified analysis. Induction of labor rates increased from 26% in 1997-2002 to 44% in 2014-2018 (adjusted rate ratio [ARR] 2.10, 95% CI 1.72-2.57) whereas elective cesarean section (ARR 0.80, 95% CI 0.59-1.07) and urgent cesarean section (ARR 0.79, 95% CI 0.63-1.00) rates appeared to decline.

CONCLUSION

Twin births decreased during the study period. International guidelines published before the Icelandic regulations may have affected twin birth rates in Iceland. Induction of labor rates for twins increased while cesarean section rates decreased.

Respectful maternity care and women's autonomy in decision making in Iceland: Application of scale instruments in a cross-sectional survey

OBJECTIVE

To explore how maternal factors are associated with women's experiences of respect and autonomy in Icelandic maternity care.

DESIGN

An online survey was developed including two measures assessing the quality of perinatal care: the Mothers on Respect Index and the Mothers' Autonomy in Decision Making Scale. Median and interquartile ranges were calculated for both scales. Logistic regression was used to calculate adjusted odds ratios and 95% confidence intervals to investigate the relationship between maternal factors and perceived low levels of respectful care and perceived low levels of autonomy in decision making.

PARTICIPANTS AND SETTING

A total of 1,402 women participated. Requirements were: Age ≥ 18 years; antenatal care and childbirth in Iceland 2015-2021; and fluency in Icelandic, English or Polish.

MEASUREMENTS AND FINDINGS

Perceived lower levels of respect were reported by migrant women [aOR 2.16 (1.55-3.00)], women with at least one social complication [aOR 2.52 (1.92-3.31)], primiparous women [aOR 1.72 (1.26-2.36)], women with at least one pregnancy complication [aOR 1.63 (1.22-2.18)] and those who gave birth by caesarean section [aOR 1.75 (1.25-2.45)]. Perceived lower levels of autonomy were reported by migrant women [aOR 1.42 (1.02-1.97)], women who had at least one social complication [aOR 2.12 (1.63-2.74)] and those who gave birth in a hospital setting [aOR 1.62 (1.03-2.55)].

KEY CONCLUSION

The results shed light on inequity in Icelandic maternity care and suggest that data from such surveys can provide valuable information on the changes that must be made in maternity health care services to ensure equity.

IMPLICATIONS FOR PRACTICE

Action must be taken to increase provision of respectful, woman-centred maternity care with an emphasis on informed decision making. Strategies to improve services for groups that have been socially marginalized, such as migrant women and women affected by social determinants of health, should be implemented and monitored.

Trends in labor induction indications: A 20-year population-based study

INTRODUCTION

Use of labor induction has increased rapidly in most middle- and high-income countries over the past decade. The reasons for the stark rise in labor induction are largely unknown. We aimed to assess the extent to which the rising rate of labor induction is explained by changes in rates of underlying indications over time.

MATERIAL AND METHODS

The study was based on nationwide data from the Icelandic Medical Birth Register on 85 620 singleton births from 1997 to 2018. The rate of labor induction and indications for induction was calculated for all singleton births in 1997-2018. Change over time was expressed as relative risk (RR), using Poisson regression with 95% confidence intervals (CI) adjusted for maternal characteristics and indications for labor induction.

RESULTS

The crude rate of labor induction rose from 12.5% in 1997-2001 to 23.9% in 2014-2018 (crude RR = 1.91, 95% CI 1.81-2.01). While adjusting for maternal characteristics had little impact, adjusting additionally for labor induction indications lowered the RR to 1.43 (95% CI 1.35-1.51). Induction was increasingly indicated from 1997-2001 to 2014-2018 by gestational diabetes (2.4%-16.5%), hypertensive disorders (7.0%-11.1%), prolonged pregnancy (16.2%-23.7%), concerns for maternal wellbeing (3.2%-6.9%) and maternal age (0.5%-1.2%). No indication was registered for 9.2% of inductions in 2014-2018 compared with 16.3% in 1997-2001.

CONCLUSIONS

Our results show that the increase in labor induction over the study period is largely explained by an increase in various underlying conditions indicating labor induction. However, indications for 9.2% of labor inductions remain unexplained and warrant further investigation.

Cesarean birth, obstetric emergencies, and adverse neonatal outcomes in Iceland during a period of increasing labor induction

BACKGROUND

The rate of labor induction has risen steeply throughout the world. This project aimed to estimate changes in the rates of adverse maternal and neonatal outcomes in Iceland between 1997 and 2018, and to assess whether the changes can be explained by an increased rate of labor induction.

METHODS

Singleton live births, occurring between 1997 and 2018, that did not start by prelabor cesarean, were identified from the Icelandic Medical Birth Register (n = 85 971). Rates of intrapartum cesarean birth (CB), obstetric emergencies, and neonatal outcomes were calculated, and adjusted risk ratios (aRRs) and 95% confidence intervals (CIs) were estimated with log-binomial regression (reference: 1997-2001). Adjustments were made for: (a) maternal characteristics, and (b) labor induction and gestational age.

RESULTS

The rate of labor induction increased from 13.6% in the period 1997-2001 to 28.1% in the period 2014-2018. The rate of intrapartum CB decreased between the periods of 1997-2001 and 2014-2018 for both primiparous (aRR 0.76, 95% CI: 0.69 to 0.84) and multiparous women (aRR 0.55, 95% CI: 0.49 to 0.63). The rate of obstetric emergencies and adverse neonatal outcomes also decreased between these time periods. Adjusting for labor induction did not attenuate these associations.

CONCLUSIONS

The rates of adverse maternal outcomes and adverse neonatal outcomes decreased over the study period. However, there was no evidence that this decrease could be explained by the increased rate of labor induction.

Comparison of stillbirth trends over two decades in Wales, United Kingdom and Western Australia: An international retrospective cohort study

BACKGROUND

Stillbirth is a critical public health issue worldwide. While the rates in high-income countries are relatively low, there are persistent between-country disparities.

OBJECTIVES

To compare stillbirth rates and trends in Wales and the State of Western Australia (WA), Australia, and provide insights into any differences.

METHODS

In this international retrospective cohort study, we pooled population-based data collections of all births ≥24 weeks' gestation (excluding terminations for congenital anomalies) between 1993 and 2015, divided into six time periods. The stillbirth rate per 1000 births was estimated for each cohort in each time period. Multivariable Poisson regression analyses, adjusted for appropriateness of growth, socio-economic status, maternal age, and multiple birth, were performed to evaluate the interaction between cohort and time period. Relative risk (RR) and 95% confidence interval (CI) for each time period and cohort were calculated.

RESULTS

There were 767 731 births (3725 stillbirths) in Wales and 648 373 (2431 stillbirths) in WA. The overall stillbirth rate declined by 15.9% over the study period in Wales (from 5.3 in 1993-96 to 4.5 per 1000 births in 2013-15; P_trend  < .01) but by 40.4% in WA (from 4.9 to 2.9 per 1000 births in WA; P_trend  < .01). Using 1993-96 in WA as the reference group, the adjusted RRs for stillbirths at 37-38 weeks' gestation in the most recent study period (2013-15) were 0.85 (95% CI 0.64, 1.13) in Wales and 0.51 (95% CI 0.36, 0.73) in WA.

CONCLUSIONS

The stillbirth rates between Wales and WA have widened in the last two decades (especially among late-term births), although the absolute rates for both are distinctly higher than the best-performing nations. While the differences may be partly explained by timing of birth and maternal life style behaviours such as smoking, it is important to identify and ameliorate the associated risk factors to support a reduction in preventable stillbirths.

The provision of epidural analgesia during labor according to maternal birthplace: a Norwegian register study

BACKGROUND

The provision of epidural analgesia during labor is ideally a shared decision between the woman and her health care provider. However, immigrant characteristics such as maternal birthplace could affect decision-making and thus access to pain relief. We aimed to assess disparities in the provision of epidural analgesia in planned vaginal birth according to maternal region of birth.

METHODS

We performed a nation-wide register study of 842,496 live-born singleton deliveries in Norway between 2000 and 2015. Maternal birthplace was categorized according to the Global Burden of Disease framework. The provision of epidural analgesia was compared in regression models stratified by parity and mode of delivery.

RESULTS

Compared to native-born women, primiparous women from Latin America/Caribbean countries with an instrumental vaginal delivery were most likely to be provided epidural analgesia (OR 2.12, 95%CI 1.69-2.66), whilst multiparous women from Sub-Saharan Africa with a spontaneous vaginal delivery were least likely to be provided epidural analgesia (OR 0.42, 95% C 0.39-0.44). Longer residence time was associated with a higher likelihood of being provided analgesia, whereas effects of maternal education varied by Global Burden of Disease group.

CONCLUSIONS

Disparities in the likelihood of being provided epidural analgesia were observed by maternal birthplace. Further studies are needed to consider whether the identified disparities represent women's own preferences or if they are the result of heterogeneous access to analgesia during labor.

Preterm births in Iceland 1997-2016: Preterm birth rates by gestational age groups and type of preterm birth

BACKGROUND

The frequency of preterm births has been increasing globally, mainly due to a rise in iatrogenic late preterm births. The aim of this study was to assess the prevalence of preterm births in Iceland during 1997-2016 by type of preterm birth.

METHODS

This study included all live births in Iceland during 1997-2016 identified from the Icelandic Medical Birth Registry. Risk of preterm birth by time period was assessed with Poisson regression models adjusted for demographic variables and indications for iatrogenic births.

RESULTS

The study population included 87 076 infants, of which 4986 (5.7%) were preterm. The preterm birth rate increased from 5.3% to 6.1% (adjusted rate ratio [ARR] = 1.16, confidence interval [CI] = 1.07-1.26) between 1997-2001 and 2012-2016 overall. The increase was only evident in multiples (ARR 1.41, 95% CI 1.21-1.65), not singletons (1.07, 0.97-1.19). The rate of late preterm births (34-36 weeks) increased significantly (1.24, 1.14-1.40), and the rate of iatrogenic preterm births more than doubled during this period even after adjustment for identified medical indications (2.40, 2.00-2.88). The rate of spontaneous preterm births decreased during the study period (0.63, 0.55-0.73), and the rate of PPROM increased (1.31, 1.09-1.57). The most common contributing indications for iatrogenic births were fetal distress (26.2%), hypertensive disorders (18.2%), and severe preeclampsia (16.9%).

CONCLUSIONS

Preterm birth rates increased in multiples in Iceland between 1997 and 2016, and late and iatrogenic preterm births increased overall. The increase in iatrogenic preterm births remained significant after adjusting for medical indications, suggesting that other factors might be affecting the rise.