Increased incidence of shoulder dystocia but a declining incidence of obstetric brachial plexus palsy in vaginally delivered infants.

INTRODUCTION: Obstetric brachial plexus palsy (OBPP) is a serious form of neonatal morbidity. The primary aim of this population-based registry study was to examine temporal trends, 1997-2019, of OBPP in infants delivered vaginally in a cephalic presentation. The secondary aim was to examine temporal changes in the incidence of associated risk factors. MATERIAL AND METHODS: This was a population-based registry study including singleton, cephalic, vaginally delivered infants, 1997-2019, in Sweden. To compare changes in the incidence rates of OBPP and associated risk factors over time, univariate logistic regression was used and odds ratios (OR) with 95% confidence intervals (CI) were calculated. RESULTS: The incidence of OBPP in infants delivered vaginally in a cephalic presentation decreased from 3.1 per 1000 births in 1997 to 1.0 per 1000 births in 2019 (OR 0.31, 95% CI 0.24-0.40). Conversely, the incidence of shoulder dystocia increased from 2.0 per 1000 in 1997 to 3.3 per 1000 in 2019 (OR 1.64, 95% CI 1.34-2.01). Over time, the proportion of women with body mass index of 30 kg/m2 or greater increased (14.5% in 2019 compared with 8.0% in year 1997, OR 1.96, 95% CI 1.89-2.03), more women had induction of labor (20.5% in 2019 compared with 8.6% in 1997, OR 2.74, 95% CI 2.66-2.83) and epidural analgesia (41.2% in 2019 compared with 29.0% in 1997, OR 1.72, 95% CI 1.68-1.75). In contrast, there was a decrease in the rate of operative vaginal delivery (6.0% in 2019, compared with 8.1% in 1997, OR 0.72, 95% CI 0.69, 0.75) and in the proportion of infants with a birthweight greater than 4500 g (2.7% in 2019 compared with 3.8% in 1997, OR 0.70, 95% CI 0.66-0.74). The decline in the incidence of these two risk factors explained only a small fraction of the overall decrease in OBPP between 1997-2002 and 2015-219. CONCLUSIONS: The incidence of OBPP in vaginally delivered infants in a cephalic presentation at birth decreased during the period 1997-2019 despite an increase in important risk factors including shoulder dystocia.

Neonatal outcomes associated with mode of subsequent birth after a previous caesarean section in a first pregnancy: a Swedish population-based register study between 1999 and 2015.

OBJECTIVE: To investigate neonatal outcomes within 28 days in the subsequent birth in women who gave birth to their first baby by caesarean section (CS). DESIGN AND SETTING: National retrospective population-based register study. A cohort of 94 451 neonates who were born in Sweden between 1999 and 2015 as a second child to a mother who had her first birth by emergency or planned caesarean. METHODS: Data were retrieved from the national registers held by Statistics Sweden and the National Board of Health and Welfare. Logistic regression was used to calculate unadjusted and adjusted ORs (aOR) with 95% CIs for each outcome. MAIN OUTCOME MEASURES: Neonatal infection, neonatal asphyxia/respiratory distress, neonatal hospital care and neonatal death within 28 days. RESULTS: Emergency CS and instrumental vaginal birth were associated with a doubled risk of neonatal infection (aOR 2.0) and planned CS with a decreased risk (aOR 0.7) compared with spontaneous vaginal birth. Compared with spontaneous vaginal birth, an increased risk of birth asphyxia and/or respiratory distress was identified with all other modes of birth (aOR 2.2-3.2). Emergency CS and instrumental vaginal birth, but not planned CS, were associated with neonatal hospital care (aOR 1.8 and 1.7) and an increased mortality rate during the neonatal period (aOR 2.9 and 3.2), compared with spontaneous vaginal birth. CONCLUSIONS: In childbirth following a previous birth by CS, spontaneous vaginal birth appears to confer better neonatal outcomes within 28 days after birth overall than other modes of birth.

A step towards better audit: The Robson Ten Group classification system for outcomes other than cesarean section.

INTRODUCTION: The Robson Ten Group Classification System is widely used for the audit of cesarean section (CS) rates. However, CS rate alone is a poor quality indicator and should be balanced with other obstetric endpoints. The aim of this study was to evaluate whether Swedish national data on obstetric outcomes other than CS, stratified by the Robson classification, could be analyzed in a useful way. MATERIAL AND METHODS: All births in Sweden from 2017 through 2020 recorded in the nationwide Swedish Pregnancy Register were categorized using the Robson classification with subdivision of some groups. Five outcomes were explored: CS, operative vaginal delivery, postpartum hemorrhage, obstetric anal sphincter injury (OASIS) and Apgar score <7 at 5 minuteutes. Rates of each outcome and contribution of each group to the total outcome rate were calculated. RESULTS: The largest Robson groups were nulliparous and multiparous women with single-term cephalic pregnancies, unscarred uterus and spontaneous labor. Intrapartum CS rates were highest for multiple pregnancies, women with induced labor after previous CS, and nulliparous women with induced labor. Nulliparous women and multiparous women with a previous CS with attempted vaginal birth had the highest operative vaginal delivery and OASIS rates. The postpartum hemorrhage rate was highest for multiple pregnancies and transverse lie, followed by prelabor CS in nulliparous and multiparous women with single-term cephalic pregnancies and unscarred uterus. The highest rates of Apgar score <7 at 5 minute were observed in preterm deliveries, multiple pregnancies, transverse lie and breech presentation. The largest contribution to the total CS rate was made by women with previous CS delivered by prelabor CS, and nulliparous women with induced or spontaneous labor. The largest contribution to all other outcomes was made by nulliparous women with spontaneous or induced labor and, notably, multiparous women with spontaneous labor and unscarred uterus. CONCLUSIONS: The Robson classification provides a useful framework for analyzing CS rates along with rates of operative vaginal delivery, OASIS, postpartum hemorrhage and low Apgar score. Parallel interpretation of several outcomes allows a systematic and multidimensional audit, helpful for families and healthcare professionals, and can be used for comparisons, assessment of trends and subpopulations.

Implementation of a revised classification for intrapartum fetal heart rate monitoring and association to birth outcome: A national cohort study.

INTRODUCTION: A revised intrapartum cardiotocography (CTG) classification was introduced in Sweden in 2017. The aims of the revision were to adapt to the international guideline published in 2015 and to adjust the classification of CTG patterns to current evidence regarding intrapartum fetal physiology. This study aimed to investigate adverse neonatal outcomes before and after implementation of the revised CTG classification. MATERIAL AND METHODS: A before-and-after design was used. Cohort I (n = 160 210) included births from June 1, 2014 through May 31, 2016 using the former CTG classification, and cohort II (n = 166 558) included births from June 1, 2018 through May 31, 2020 with the revised classification. Data were collected from the Swedish Pregnancy and Neonatal Registers. The primary outcome was moderate to severe neonatal hypoxic ischemic encephalopathy (HIE 2-3). Secondary outcomes were birth acidemia (umbilical artery pH <7.05 and base excess < -12 mmol/L or pH <7.00), A-criteria for neonatal hypothermia treatment, 5-min Apgar scores <4 and <7, neonatal seizures, meconium aspiration, neonatal mortality and delivery mode. Logistic regression was used (period II vs period I), and results are presented as adjusted odds ratios (aORs) with 95% confidence intervals (95% CIs). RESULTS: There were no statistically significant differences in HIE 2-3 (aOR 1.27; 95% CI 0.97-1.66), proportion of neonates meeting A-criteria for hypothermia treatment (aOR 0.96; 95% CI 0.89-1.04) or neonatal mortality (aOR 0.68; 95% CI 0.39-1.18) between the cohorts. Birth acidemia (aOR 1.36; 95% CI 1.25-1.48), 5-min Apgar scores <7 (aOR 1.27; 95% CI 1.18-1.36) and <4 (aOR 1.40; 95% CI 1.17-1.66) occurred more often in cohort II. The absolute risk difference for HIE 2-3 was 0.02% (95% CI 0.00-0.04). Operative delivery (vacuum or cesarean) rates were lower in cohort II (aOR 0.82; 95% CI 0.80-0.85 and aOR 0.94; 95% CI 0.91-0.97, respectively). CONCLUSIONS: Although not statistically significant, a small increase in the incidence of HIE 2-3 after implementation of the revised CTG classification cannot be excluded. Operative deliveries were fewer but incidences of acidemia and low Apgar scores were higher in the latter cohort. This warrants further in-depth analyses before a full re-evaluation of the revised classification can be made.

Fetal scalp blood sampling during second stage of labor - analyzing lactate or pH? A secondary analysis of a randomized controlled trial.

BACKGROUND: Cardiotocography (CTG) is a widely used method for assessing fetal wellbeing during labor. It is well-known that CTG has high sensitivity but low specificity. To avoid unnecessary operative interventions, adjunctive methods such as fetal blood sampling (FBS) are used. Few studies have looked into whether FBS can be used during second stage of labor, and in that case, which of the methods (lactate or pH) are preferred. OBJECTIVE: To evaluate clinical effectiveness of measuring lactate versus pH in preventing birth acidemia when FBS was performed during second stage of labor. METHODS: Secondary analysis of a randomized controlled trial . Thousand three hundred and thirty-eight women with a singleton pregnancy, cephalic presentation, gestational age ≥34 weeks, and indication for FBS during second stage of labor were included. MAIN OUTCOME MEASURES: Metabolic acidemia (pH <7.05 and base deficit >12 mmol/l) or pH < 7.00 in cord arterial blood at birth. SECONDARY OUTCOMES: A composite outcome (metabolic acidemia, pH <7 or Apgar score <4), and rates of operative deliveries. RESULTS: Metabolic acidemia occurred in 4.1% in the lactate versus 5.1% in the pH group (relative risk (RR): 0.80; 95% confidence interval (CI): 0.48-1.35) and pH <7 in 1.4% versus 2.8% (RR: 0.51, 95% CI: 0.23-1.13). Composite outcome was found in 3.8 versus 4.9%, respectively (RR: 0.76; 95% CI: 0.46-1.26). No difference in total operative interventions was found. More cesarean deliveries were performed in the lactate group (16.5 vs. 12.4%; RR: 1.33; 95% CI: 1.02-1.74). CONCLUSION: When analyzing lactate or pH in fetal scalp blood during second stage of labor neonatal outcomes were comparable. The frequency of total operative interventions was similar but more cesarean deliveries were performed in the lactate group.

Induction of labour at 41 weeks of gestation versus expectant management and induction of labour at 42 weeks of gestation: A cost-effectiveness analysis.

OBJECTIVE: To assess the cost-effectiveness of induction of labour (IOL) at 41 weeks of gestation compared with expectant management until 42 weeks of gestation. DESIGN: A cost-effectiveness analysis alongside the Swedish Post-term Induction Study (SWEPIS), a multicentre, randomised controlled superiority trial. SETTING: Fourteen Swedish hospitals during 2016-2018. POPULATION: Women with an uncomplicated singleton pregnancy with a fetus in cephalic position were randomised at 41 weeks of gestation to IOL or to expectant management and induction at 42 weeks of gestation. METHODS: Health benefits were measured in life years and quality-adjusted life years (QALYs) for mother and child. Total cost per birth was calculated, including healthcare costs from randomisation to discharge after delivery, for mother and child. Incremental cost-effectiveness ratios (ICERs) were calculated by dividing the difference in mean cost between the trial arms by the difference in life years and QALYs, respectively. Sampling uncertainty was evaluated using non-parametric bootstrapping. MAIN OUTCOME MEASURES: The cost per gained life year and per gained QALY. RESULTS: The differences in life years and QALYs gained were driven by the difference in perinatal mortality alone. The absolute risk reduction in mortality was 0.004 (from 6/1373 to 0/1373). Based on Swedish life tables, this gives a mean gain in discounted life years and QALYs of 0.14 and 0.12 per birth, respectively. The mean cost per birth was €4108 in the IOL group (n = 1373) and €4037 in the expectant management group (n = 1373), with a mean difference of €71 (95% CI -€232 to €379). The ICER for IOL compared with expectant management was €545 per life year gained and €623 per QALY gained. Confidence intervals were relatively wide and included the possibility that IOL had both lower costs and better health outcomes. CONCLUSIONS: Induction of labour at 41 weeks of gestation results in a better health outcome and no significant difference in costs. IOL is cost-effective compared with expectant management until 42 weeks of gestation using standard threshold values for acceptable cost per life year/QALY. TWEETABLE ABSTRACT: Induction of labour at 41 weeks of gestation is cost-effective compared with expectant management until 42 weeks of gestation.

Efficacy and safety of oral misoprostol vs transvaginal balloon catheter for labor induction: An observational study within the SWEdish Postterm Induction Study (SWEPIS).

INTRODUCTION: Induction of labor is increasing. A common indication for induction of labor is late term and postterm pregnancy at 41 weeks or more. We aimed to evaluate if there are any differences regarding efficacy, safety, and women's childbirth experience between oral misoprostol and transvaginal balloon catheter for cervical ripening in women with a low-risk singleton pregnancy and induction of labor at 41+0 to 42+0 to 1 weeks of gestation. MATERIAL AND METHODS: In this observational study, based on data from the Swedish Postterm Induction Study (SWEPIS), a multicenter randomized controlled trial, a total of 1213 women with a low-risk singleton pregnancy at 41 to 42 weeks of gestation were induced with oral misoprostol (n = 744) or transvaginal balloon catheter (n = 469) at 15 Swedish delivery hospitals. The primary efficacy outcome was vaginal delivery within 24 h and primary safety outcomes were neonatal and maternal composite adverse outcomes. Secondary outcomes included time to vaginal delivery and mode of delivery. Women's childbirth experience was assessed with the Childbirth Experience Questionnaire (CEQ 2.0) and visual analog scale. We present crude and adjusted mean differences and relative risks (RR) with 95% CI. Adjustment was performed for a propensity score based on delivery hospital and baseline characteristics including Bishop score. RESULTS: Vaginal delivery within 24 h was significantly lower in the misoprostol group compared with the balloon catheter group (46.5% [346/744] vs 62.7% [294/469]; adjusted RR 0.76 95% CI 0.640.89]). Primary neonatal and maternal safety outcomes did not differ between groups (neonatal composite 3.5% [36/744] vs 3.2% [15/469]; adjusted RR 0.77 [95% CI 0.31-1.89]; maternal composite 2.3% [17/744] vs 1.9% [9/469]; adjusted RR 1.70 [95% CI 0.58-4.97]). Adjusted mean time to vaginal delivery was increased by 3.8 h (95% CI 1.3-6.2 h) in the misoprostol group. Non-operative vaginal delivery and cesarean delivery rates did not differ. Women's childbirth experience was positive overall and similar in both groups. CONCLUSIONS: Induction of labor with oral misoprostol compared with a transvaginal balloon catheter was associated with a lower probability of vaginal delivery within 24 h and a longer time to vaginal delivery. However, primary safety outcomes, non-operative vaginal delivery, and women's childbirth experience were similar in both groups. Therefore, both methods can be recommended in women with low-risk postdate pregnancies.

Induction of labour at 41 weeks versus expectant management and induction of labour at 42 weeks (SWEdish Post-term Induction Study, SWEPIS): multicentre, open label, randomised, superiority trial.

OBJECTIVE: To evaluate if induction of labour at 41 weeks improves perinatal and maternal outcomes in women with a low risk pregnancy compared with expectant management and induction of labour at 42 weeks. DESIGN: Multicentre, open label, randomised controlled superiority trial. SETTING: 14 hospitals in Sweden, 2016-18. PARTICIPANTS: 2760 women with a low risk uncomplicated singleton pregnancy randomised (1:1) by the Swedish Pregnancy Register. 1381 women were assigned to the induction group and 1379 were assigned to the expectant management group. INTERVENTIONS: Induction of labour at 41 weeks and expectant management and induction of labour at 42 weeks. MAIN OUTCOME MEASURES: The primary outcome was a composite perinatal outcome including one or more of stillbirth, neonatal mortality, Apgar score less than 7 at five minutes, pH less than 7.00 or metabolic acidosis (pH <7.05 and base deficit >12 mmol/L) in the umbilical artery, hypoxic ischaemic encephalopathy, intracranial haemorrhage, convulsions, meconium aspiration syndrome, mechanical ventilation within 72 hours, or obstetric brachial plexus injury. Primary analysis was by intention to treat. RESULTS: The study was stopped early owing to a significantly higher rate of perinatal mortality in the expectant management group. The composite primary perinatal outcome did not differ between the groups: 2.4% (33/1381) in the induction group and 2.2% (31/1379) in the expectant management group (relative risk 1.06, 95% confidence interval 0.65 to 1.73; P=0.90). No perinatal deaths occurred in the induction group but six (five stillbirths and one early neonatal death) occurred in the expectant management group (P=0.03). The proportion of caesarean delivery, instrumental vaginal delivery, or any major maternal morbidity did not differ between the groups. CONCLUSIONS: This study comparing induction of labour at 41 weeks with expectant management and induction at 42 weeks does not show any significant difference in the primary composite adverse perinatal outcome. However, a reduction of the secondary outcome perinatal mortality is observed without increasing adverse maternal outcomes. Although these results should be interpreted cautiously, induction of labour ought to be offered to women no later than at 41 weeks and could be one (of few) interventions that reduces the rate of stillbirths. TRIAL REGISTRATION: Current Controlled Trials ISRCTN26113652.

Inter-hospital variations in health outcomes in childbirth care in Sweden: a register-based study.

OBJECTIVE: The objective of this study was to estimate case mix adjusted variations in central indicators of health outcomes in childbirth care and to assess whether hospitals who perform well on one indicator also perform well on others. DESIGN: Register-based study using regional administrative data, linked to clinical data and population data. SETTING: Twenty-one hospitals in seven Swedish regions covering 67% of deliveries in Sweden. PARTICIPANTS: The study included 139 756 women who gave birth in 2011 and 2012. INTERVENTION(S): N/A. MAIN OUTCOME MEASURE(S): Four indicators of health outcomes were studied: obstetric anal sphincter injuries (OASIS), haemorrhage >1000 ml, postpartum infection and Apgar <4 at 5 min. Variations between hospitals were estimated using fixed effects logistic regression, adjusted for numerous sociodemographic and clinical characteristics. RESULTS: Significant variations after case mix adjustment were observed for all four indicators. If all hospitals had performed as the average of the top five hospitals for each indicator, a total of 890 OASIS, 2700 haemorrhages, 1500 postpartum infections and 180 instances of low Apgar would have been avoided. A certain degree of correlation was observed between different indicators of outcomes. However, no hospital had a statistically significant higher or lower rate across all four indicators of health outcomes. CONCLUSIONS: The significant variations in all four indicators demonstrate a potential for improvement in performance at all studied hospitals. Hospital performance was not consistent across different indicators of outcomes and all hospitals have potential for improvement in certain aspects of labour management.

Symptomatic recovery and pharmacological management in a clinical cohort with peripartum cardiomyopathy.

AIM: We aimed to characterize the clinical course with focus on pharmacological management of peripartum cardiomyopathy (PPCM) in Sweden. METHODS: Twenty-four consecutive patients were retrospectively identified among women presenting with PPCM in Western Sweden. Of these, 14 had concomitant preeclampsia. There was only one fatality. The mean (standard deviation) left ventricular ejection fraction (LVEF) at diagnosis was 35.0 ± 9.9%. Ten women, 47.6%, required intensive care unit (ICU) admission. All patients received ß-blockers (BB) and angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers (ACE-I/ARB), which were tapered off over a mean/median period of 3.3/2.5 years with only one case of worsening heart failure. The mean follow-up for medication was 7.9 ± 2.6 years. Early and late/non-recovery was defined as New York Heart Association (NYHA) functional class I and NYHA II-IV at one year, respectively. Late recovery was associated with larger LVEDD at diagnosis (56.8 versus 62.4 mm) was associated with late recovery, p = .02. RESULTS AND CONCLUSIONS: PPCM had an overall good prognosis in this cohort. Left ventricular dilation at presentation was a predictor of worse prognosis. Concurrent preeclampsia was common, but was associated with better prognosis. Medication was safely discontinued in 75% of patients.

Perinatal complications in patients with unisutural craniosynostosis: An international multicentre retrospective cohort study.

PURPOSE: Craniosynostosis may lead to hampered fetal head molding and birth complications. To study the interaction between single suture craniosynostosis and delivery complications, an international, multicentre, retrospective cohort study was performed. MATERIALS AND METHODS: All infants born between 2006 and 2012 in the Netherlands and Sweden with sagittal or metopic suture synostosis were included. All births were included as a reference population. The primary outcome measure was rate of medically assisted labor. The secondary outcomes included method of conception, term of birth and fetal position. RESULTS: We included 152 trigonocephaly patients, 272 scaphocephaly patients and 1.954.141 controls. A higher rate of assisted reproductive technology (ART) was found in patients with trigonocephaly (13%) and scaphocephaly (7%) compared to controls (3%, p < 0.001). Scaphocephaly resulted in more postterm births (8% vs 4%, p < 0.001). Trigonocephaly patients showed more preterm births (11% vs 6%, p < 0.001), breech position was more frequent (10% vs 4%, p = 0.003) and labor was more often induced. Rate of assisted delivery, including cesarean section, was significantly higher in both patient groups. CONCLUSIONS: Scaphocephaly leads to more postterm births and an increased rate of cesarean sections. Trigonocephaly is related to ART, and in addition higher rates of breech position and cesarean section are found. Prenatal detection of single suture craniosynostosis could improve perinatal care.

Case mix adjusted variation in cesarean section rate in Sweden.

INTRODUCTION: Cesarean section (CS) rate is a well-established indicator of performance in maternity care and is also related to resource use. Case mix adjustment of CS rates when performing comparisons between hospitals is important. The objective of this study was to estimate case mix adjusted variation in CS rate between hospitals in Sweden. MATERIAL AND METHODS: In total, 139 756 deliveries in 2011 and 2012 were identified in administrative systems in seven regions covering 67% of all deliveries in Sweden. Data were linked to the Medical birth register and population data. Twenty-three different sociodemographic and clinical characteristics were used for adjustment. Analyses were performed for the entire study population as well as for two subgroups. Logistic regression was used to analyze differences between hospitals. RESULTS: The overall CS rate was 16.9% (hospital minimum-maximum 12.1-22.6%). Significant variations in CS rate between hospitals were observed after case mix adjustment: hospital odds ratios for CS varied from 0.62 (95% CI 0.53-0.73) to 1.45 (95% CI 1.37-1.52). In nulliparous, cephalic, full-term, singletons the overall CS rate was 14.3% (hospital minimum-maximum: 9.0-19.0%), whereas it was 4.7% for multiparous, cephalic, full-term, singletons with no previous CS (hospital minimum-maximum: 3.2-6.7%). In both subgroups significant variations were observed in case mix adjusted CS rates. CONCLUSIONS: Significant differences in CS rate between Swedish hospitals were found after adjusting for differences in case mix. This indicates a potential for fewer interventions and lower resource use in Swedish childbirth care. Best practice sharing and continuous monitoring are important tools for improving childbirth care.

Heart Failure in Late Pregnancy and Postpartum: Incidence and Long-Term Mortality in Sweden From 1997 to 2010.

BACKGROUND: Heart failure (HF) in late pregnancy and postpartum (HFPP), of which peripartum cardiomyopathy (PPCM) constitutes the larger part, is still a rare occurrence in Sweden. Population-based data are scarce. Our aim was to characterize HFPP and determine the incidence and mortality in a Swedish cohort. METHODS AND RESULTS: Through merging data from the National Inpatient, Cause of Death, and Medical Birth Registries, we identified ICD-10 codes for HF and cardiomyopathy within 3 months before delivery to 6 months postpartum. Each case was assigned 5 age-matched control subjects from the Medical Birth Registry. From 1997 to 2010, 241 unique HFPP case subjects and 1063 matched control subjects were identified. Mean incidence was 1 in 5719 deliveries. HFPP was strongly associated with preeclampsia (odds ratio [OR] 11.91, 95% confidence interval [CI] 7.86-18.06), obesity (OR 2.5, 95% CI 1.7-3.7), low- and middle-income country (LMIC) of origin (OR 1.73, 95% CI 1.14-2.63), and twin deliveries (OR 4.39 CI 95% 2.24-8.58). By the end of the study period deaths among cases were >35-fold those of controls: 9 cases (3.7 %) and 1 control (0.1 %; P < .0001). Among control subjects, 17.9% of mortalities occurred within 3 years, of diagnosis compared with 100% among cases. CONCLUSIONS: The mean incidence and mortality among women with HFPP in Sweden from 1997 to 2010 was low but carried a marked excess risk of death compared with control subjects and was strongly linked to preeclampsia, obesity, multifetal births, and LMIC origin of the mother.

Case mix adjustment of health outcomes, resource use and process indicators in childbirth care: a register-based study.

BACKGROUND: Unwarranted variation in care practice and outcomes has gained attention and inter-hospital comparisons are increasingly being used to highlight and understand differences between hospitals. Adjustment for case mix is a prerequisite for meaningful comparisons between hospitals with different patient populations. The objective of this study was to identify and quantify maternal characteristics that impact a set of important indicators of health outcomes, resource use and care process and which could be used for case mix adjustment of comparisons between hospitals. METHODS: In this register-based study, 139 756 deliveries in 2011 and 2012 were identified in regional administrative systems from seven Swedish regions, which together cover 67 % of all deliveries in Sweden. Data were linked to the Medical birth register and Statistics Sweden's population data. A number of important indicators in childbirth care were studied: Caesarean section (CS), induction of labour, length of stay, perineal tears, haemorrhage > 1000 ml and post-partum infections. Sociodemographic and clinical characteristics deemed relevant for case mix adjustment of outcomes and resource use were identified based on previous literature and based on clinical expertise. Adjustment using logistic and ordinary least squares regression analysis was performed to quantify the impact of these characteristics on the studied indicators. RESULTS: Almost all case mix factors analysed had an impact on CS rate, induction rate and length of stay and the effect was highly statistically significant for most factors. Maternal age, parity, fetal presentation and multiple birth were strong predictors of all these indicators but a number of additional factors such as born outside the EU, body mass index (BMI) and several complications during pregnancy were also important risk factors. A number of maternal characteristics had a noticeable impact on risk of perineal tears, while the impact of case mix factors was less pronounced for risk of haemorrhage > 1000 ml and post-partum infections. CONCLUSIONS: Maternal characteristics have a large impact on care process, resource use and outcomes in childbirth care. For meaningful comparisons between hospitals and benchmarking, a broad spectrum of sociodemographic and clinical maternal characteristics should be accounted for.

Study protocol of SWEPIS a Swedish multicentre register based randomised controlled trial to compare induction of labour at 41 completed gestational weeks versus expectant management and induction at 42 completed gestational weeks.

BACKGROUND: Observational data shows that postterm pregnancy (≥42 gestational weeks, GW) and late term pregnancy (≥41 GW), as compared to term pregnancy, is associated with an increased risk for adverse outcome for the mother and infant. Standard care in many countries is induction of labour at 42 GW. There is insufficient scientific support that induction of labour at 41 GW, as compared with expectant management and induction at 42 GW will reduce perinatal mortality and morbidity without an increase in operative deliveries, negative delivery experiences or higher costs. Large randomised studies are needed since important outcomes; such as perinatal mortality and hypoxic ischaemic encephalopathy are rare events. METHODS/DESIGN: A total of 10 038 healthy women ≥18 years old with a normal live singleton pregnancy in cephalic presentation at 41 GW estimated with a first or second trimester ultrasound, who is able to understand oral and written information will be randomised to labour induction at 41 GW (early induction) or expectant management and induction at 42 GW (late induction). Women will be recruited at university clinics and county hospitals in Sweden comprising more than 65 000 deliveries per year. Primary outcome will be a composite of stillbirth, neonatal mortality and severe neonatal morbidity. Secondary outcomes will be other adverse neonatal and maternal outcomes, mode of delivery, women's experience, cost effectiveness and infant morbidity up to 3 months of age. Data on background variables, obstetric and neonatal outcomes will be obtained from the Swedish Pregnancy Register and the Swedish Neonatal Quality Register. Data on women's experiences will be collected by questionnaires after randomisation and 3 months after delivery. Primary analysis will be intention to treat. The statistician will be blinded to group and intervention. DISCUSSION: It is important to investigate if an intervention at 41 GW is superior to standard care in order to reduce death and lifelong disability for the children. The pregnant population, >41 GW, constitutes 15-20% of all pregnancies and the results of the study will thus have a great impact. The use of registries for randomisation and collection of outcome data represents a unique and new study design. TRIAL REGISTRATION: The study was registered in Current Controlled Trials, ISRCTN26113652 the 30(th) of March 2015 (DOI 10.1186/ISRCTN26113652 ).

Transvaginal sonographic evaluation of cervical length in the second trimester of asymptomatic singleton pregnancies, and the risk of preterm delivery.

OBJECTIVE: To evaluate cervical length in asymptomatic women with singleton pregnancies in the second trimester by means of transvaginal ultrasonography, and to examine the relation between cervical length and spontaneous preterm delivery. DESIGN: Observational, prospective study. SETTING: A university hospital and a county hospital in Western Sweden. POPULATION: A total of 2122 asymptomatic women with live singleton pregnancies without fetal anomalies. METHODS: Cervical length was measured at between 16 and 23 weeks of gestation by means of transvaginal ultrasonography. Data were analysed using logistic regression analysis. MAIN OUTCOME MEASURES: Cervical length in relation to spontaneous preterm delivery <34 weeks (primary outcome) and <37 weeks of gestation (secondary outcome). RESULTS: Eleven women had a cervical length of ≤25 mm (0.5%) and 73 women had a cervical length of ≤30 mm (3.4%). Spontaneous preterm delivery at <34 weeks occurred in 22/2061 women (1.1%) and at <37 weeks in 87/2061 women (4.2%). There was a significant association between cervical length and spontaneous preterm delivery at <34 weeks (odds ratio 1.78; 95% confidence interval 1.19-2.65 for a decrease of cervical length by 5 mm) but no significant association at <37 weeks. CONCLUSIONS: The rate of short cervical length of ≤25 mm was lower than expected. The study confirmed the increased risk of spontaneous preterm delivery in women with a short cervix, although the analysis was based on only a few cases. In Sweden, a larger study is needed to evaluate the prevalence of short cervical length and the possible association with preterm delivery before universal screening can be recommended.