Outcomes of gallstone disease during pregnancy: a population based data linkage study

Background Gallstone disease is a leading indication for non-obstetric abdominal surgery during pregnancy. There are limited whole population data on maternal and neonatal outcomes. This population-based study aims to describe the outcomes of gallstone disease during pregnancy in an Australian setting. Methods Linked hospital, birth and mortality data for all women with singleton pregnancies in New South Wales, Australia, 2001-2012 were analysed. Exposure of interest was gallstone disease (acute biliary pancreatitis, gallstones with/without cholecystitis). Outcomes including preterm birth (spontaneous and planned), readmission, morbidity and mortality (maternal and neonatal) were compared between pregnancies with and without gallstone disease and within disease subtypes. Adjusted risk ratios (aRRs) and 99% confidence intervals were estimated using modified Poisson regression and adjusted for maternal and pregnancy factors. Results Among 1,064,089 pregnancies, 1882 (0.18%) had gallstone disease. Of these, 239 (12.7%) had an antepartum cholecystectomy and 1643 (87.3%) were managed conservatively. Of those managed conservatively, 319 (19.0%) had a postpartum cholecystectomy. Gallstone disease was associated with increased risk of preterm birth (aRR 1.3, 99% CI 1.1, 1.6) particularly planned preterm birth (aRR 1.6, 99% CI 1.2, 2.1), maternal morbidity (aRR 1.6, 99% CI 1.1, 2.3), maternal readmission (aRR 4.7, 99% CI 4.2, 5.3), and neonatal morbidity (aRR 1.4, 99% CI 1.1, 1.7). Surgery was associated with decreased risk of maternal readmission (aRR 0.4, 99% CI 0.2, 0.7). Conclusions Gallstone disease during pregnancy was associated with adverse maternal and neonatal outcomes. Most women with gallstone disease during pregnancy are managed conservatively. Surgical management was associated with decreased risk of readmission.NHMRC, AR

Prevalence of noncaesarean uterine surgical scars in a maternity population

NHMR

Postnatal care utilization by Vietnamese women

Only 70% of Vietnamese attend any postnatal health care and this is primarily for infant immunization.NHMRC, Học Mãi Foundatio

Variation in hospital caesarean section rates for women with at least one previous caesarean section: a population based cohort study

Background: Internationally, repeat caesarean sections (Robson Classification Group 5) make the single largest contribution to overall caesarean section rates and hospital-to-hospital variation has been reported. It is unknown if case-mix and hospital factors explain variation in hospital rates of repeat caesarean sections and whether these rates are associated with maternal and neonatal morbidity. Methods: This population-based record linkage study utilised data from New South Wales, Australia between 2007 and 2011. The study population included all maternities with prior caesarean section that were singleton, cephalic and at term. Multilevel regression models were used with primary outcomes of ‘planned repeat caesarean section’ and ‘intra-partum caesarean section’. The associations between quintiles of risk-adjusted hospital rates of planned and intra-partum repeat caesarean sections and case-mix adjusted maternal and neonatal morbidity rates, postpartum haemorrhage rates and Apgar score below 7 at five minutes rates were also assessed. Results: Of 61894 maternities with a prior caesarean section in 81 hospitals, 82.1% resulted in a repeat caesarean section and 17.9% in vaginal birth. Of the caesarean sections, 72.7% were planned and 9.4% were unplanned intra-partum. Crude hospital rates of planned caesarean sections ranged from 50.7% to 98.4%. Overall 49.0% of between-hospital variation in planned repeat caesarean section rates was explained by patient characteristics (17.3%) and hospital factors (31.7%). Increased odds of planned caesarean section were associated with private hospital status and lower hospital propensity for vaginal birth after caesarean. There were no associations between quintiles of planned repeat caesarean section and adjusted morbidity rates. Crude rates of intra-partum caesarean section ranged from 12.9% to 71.9%. In total, 27.5% of between hospital variation in rates of intra-partum caesarean section was explained by patient (19.5%) and hospital factors (8.0%). The adjusted morbidity rates differed among quintiles of hospital intra-partum caesarean section rates, but were influenced by a few hospitals with outlying rates. 3 Conclusions: About half of the variation in hospital planned repeat caesarean section rates was explained and strategies aimed at modifying these rates should not affect morbidity rates. Intra-partum caesarean sections were associated with morbidity but not in a systematic mannerNHMRC, AR

Methods of classification for women undergoing induction of labour: a systematic review and novel classification system

Background: The lack of reproducible methods for classifying women having an induction of labour (IOL) has led to controversies regarding the association of IOL and health outcomes for mother and baby. Objectives: To identify research papers that describe a methodology for classifying women having an IOL, and to evaluate the utility of these methods of classification for clinical, research and surveillance purposes. Search strategy: We conducted electronic searches in CINAHL, EMBASE and WEB of KNOWLEDGE from database inception until Oct 2013 and searched reference lists. Selection criteria: Two reviewers independently assessed eligibility. Studies had to describe a method for classifying women with an IOL using a minimum of two categories, regardless of whether or not this was the main purpose of the study. Data collection: Data were extracted on study characteristics, quality and results. Pre-specified criteria were used to evaluate the utility of these methods of classification for IOL. Main results: Seven studies met the inclusion criteria. All studies categorised women according to the presence or absence of a medical indication for IOL. Uncertainties and/or deficiencies were identified across all methods of classification related to the criteria of total inclusivity, reproducibility, clinical utility, implementability and data availability limiting their usefulness. Conclusion: Current methods of classifying women with an IOL are inadequate for clinical, research and surveillance purposes. Limitations with classification systems based on medical indications suggest that an alternative method of classification is required for women having IOL

Variation in and factors associated with timing of low risk, pre-labour repeat caesarean sections in NSW, 2008-2011

In April 2007, the New South Wales (NSW) Ministry of Health released an evidence-based policy directive requiring that ‘where there are no compelling medical indications, elective or pre-labour caesarean section does not occur prior to 39 completed week’s gestation’. This study describes variation in and factors associated with hospital rates of early (37-38 weeks gestation), low risk pre-labour repeat caesarean section at term. Linked birth and hospital data for low-risk, pre-labour repeat caesarean sections in NSW in 2008-2011 were analysed using multi-level regression modelling. Rates were adjusted for casemix and hospital factors. In 2008-2011, there were 15,163 pre-labour repeat caesarean sections among low risk women in NSW. Overall, 34.7% of low risk pre-labour repeat caesarean sections occurred before 39 weeks gestation. Casemix and hospital factor adjusted NSW public hospital rates of early (37-38 weeks gestation), low risk, pre-labour repeat caesarean section at term varied widely (16.3%-67.5%). Smoking, private health care, assisted reproductive technology, higher parity, a non-caesarean uterine scar and delivering in a hospital with CPAP facilities were associated with higher odds of early delivery. Hospitals with higher rates of low risk deliveries and higher propensity for vaginal birth after caesarean rates had lower odds of early delivery. The findings suggest poor uptake of the policy for pre-labour caesarean from 39 weeks. Large between-hospital variation persisted following adjustment, suggesting that non-medical factors are related to timing of low risk, pre-labour caesarean section. Further strategies are needed to enhance adherence to evidence-based policy.ARC, NHMR

Prelabor cesarean delivery for twin pregnancies close to term is associated with reduced mortality

Objectives: To examine short and longer term outcomes for twins born at or near term, comparing prelabor cesarean delivery (CD) to birth after trial of labor. Methods: A retrospective cohort of twin pregnancies delivered ≥ 36 weeks gestation from 2000 to 2009. Pregnancies with an antenatal death, lethal anomaly, birthweight discordance ≥25% or birthweight 4000 grams were excluded. Outcomes included severe hypoxia, stillbirth and neonatal death, and hospital admissions or death during the first 5 years of life. Results: 45.3% of 7099 twin pregnancies were delivered by prelabor CD. Compared to delivery after labor, prelabor CD was associated with significantly reduced risks of adverse infant outcomes including severe birth hypoxia (0.08% vs. 0.75%, RR 0.10, 95% CI 0.04-0.26), neonatal death (0.00% vs. 0.15%, RR 0.05, 95% CI 0.00-0.82), and death up to 5 years of age (0.16% vs. 0.40%, RR 0.41, 95% CI 0.20-0.85). Whereas total mortality for first twins was similar after labor (0.15%) compared to prelabor CD (0.16%), total mortality was four times more common in second twins born after labor (0.64%) compared to second twins born after prelabor CD (0.16%). Conclusions: Twin pregnancies at and beyond 36 weeks who are delivered after labor have increased risks for birth outcomes associated with hypoxia. These risks do not result in increased mortality in the first twin, but second twins have significantly increased mortality up to 5 years of age. However, the absolute mortality rate for relatively uncomplicated twin pregnancies born at or near term is low.The New South Wales (NSW) Ministry of Health provided access to the population health data and the NSW Centre for Health Record Linkage linked the data sets. This work was supported by an Australian National Health and Medical Research Council (NHMRC) Centre for Research Excellence Grant (1001066). CLR is supported by a NHMRC Senior Research Fellowship (#APP1021025)

Variation in hospital caesarean rates among nulliparae at term is unexplained and unrelated to maternal or neonatal outcome: a population based cohort study

OBJECTIVE To explore variation in hospital caesarean rates for nulliparous women; determine whether casemix, labour and delivery, and hospital factors explain the variation and examine the association between hospital caesarean rates and outcomes. DESIGN Population-based cohort study. SETTING New South Wales, 2009-2010. POPULATION Nulliparous women with singleton cephalic live births at term. METHODS Random effects multilevel logistic regression models using linked hospital discharge and birth data. MAIN OUTCOME MEASURES Prelabour, and intrapartum caesarean rates following spontaneous labour or labour induction; maternal and neonatal severe morbidity rates. RESULTS Of 67,239 nulliparous women, 4,902 (7.3%) had prelabour caesareans, 39,049 (58.1%) had spontaneous labour and 23,288 (34.6%) had induction of labour. Overall, there were 18,875 (28.1%) caesareans, with labour inductions twice as likely to end in an intrapartum caesarean than spontaneous labour (34.0% versus 15.5%). Variation in caesarean rates for term nulliparae 3 After adjusting for casemix, labour and delivery, and hospital factors, the overall variation in caesarean rates decreased by 78% for prelabour caesareans; for intrapartum caesarean by 52% following spontaneous labour and by 9% following labour induction. However, adjusting for labour and delivery practices increased the unexplained variation in intrapartum caesareans. The rates of severe maternal and neonatal morbidity were not significantly different across caesarean rate quintile groups, except for women in spontaneous labour, where the hospitals in the lowest caesarean quintile had the lowest neonatal morbidity rate. CONCLUSIONS Differences in clinical practice were substantial contributors to variations in intrapartum caesarean rates. Strategies aiming at lowering the caesarean rate should not adversely affect maternal or neonatal outcome.National Health and Medical Research Council Centre for Research Excellence Grant (1001066) and the New South Wales Population Health and Health Services Research Support Program. NHMRC Senior Research Fellowship (APP1021025)

Variation in hospital rates of induction of labour: a population-based record linkage study

BACKGROUND: Understanding the extent of hospital heterogeneity in induction of labour (IOL) practices to identify areas of practice improvement may result in improved maternity outcomes. We examined inter-hospital variation in rates of IOL to identify potential targets to reduce high rates of practice variation. METHODS: Population-based record linkage study of all births of ≥24 weeks gestation in 72 hospitals in New South Wales, Australia, 2010-2011. Births were categorized into 10 mutually exclusive groups, derived from the Robson caesarean section (CS) classification. These groups were categorised by parity, plurality, fetal presentation, prior CS and gestational age. Multilevel logistic regression was used to examine variation in hospital IOL rates by the groups, adjusted for differences in casemix. RESULTS: The overall IOL rate was 26.7% (46,922 of 175,444 maternities were induced), ranging from 9.7%- 41.2% (interquartile range 21.8%- 29.8%) between hospitals. Nulliparous and multiparous women at 39-40 weeks gestation with a singleton cephalic birth were the greatest contributors to the overall IOL rate (23.5% and 20.2% of all IOL respectively), and had persisting high unexplained variation after adjustment for casemix (adjusted hospital IOL rates ranging from 11.8%- 44.9% and 7.1%- 40.5% respectively). In contrast, there was little variation in inter-hospital IOL rates among multiparous women with a singleton cephalic birth at ≥41 weeks gestation, women with singleton non-cephalic pregnancies, and women with multifetal pregnancies. CONCLUSION: Seven of the 10 groups showed high or moderate unexplained variation in inter-hospital IOL rates, most pronounced for women at 39-40 weeks gestation with a singleton cephalic birth. Outcomes associated with divergent practice require determination, which may guide strategies to reduce practice variation.NHMRC, AR

Heart valve prostheses in pregnancy: Outcomes for women and their babies

Background: As the prognosis of women with prosthetic heart valves improves more of these individuals are contemplating and undertaking pregnancy. Accurate knowledge of perinatal outcomes is essential, assisting counselling and guiding care. The aim of this study was to assess outcomes in a contemporary population of women with heart valve prostheses undertaking pregnancy, and to compare outcomes for women with mechanical and bioprosthetic prostheses. Method and results: Longitudinally-linked population health datasets containing birth and hospital admissions data were obtained for all women giving birth in New South Wales, Australia, 2000-2011. This included information identifying presence of maternal prosthetic heart valve. Cardiovascular and birth outcomes were evaluated. Among 1 144 156 pregnancies, 136 involved women with a heart valve prosthesis (1 in 10 000). No maternal mortality was seen among these women, although the relative risk for an adverse event was higher than the general population, including severe maternal morbidity (13.9% v. 1.4%, RR=9.96, 95% CI 6.32-15.7), major maternal cardiovascular event (4.4% v. 0.1%, RR 34.6, 95% CI 14.6-81.6), preterm birth (18.3% v. 6.6%, RR=2.77, 95% CI 1.88-4.07) and small-for-gestational-age infants (19.3% v. 9.5%, RR=2.12, 95% CI 1.47-3.06). There was a trend towards increased maternal and perinatal morbidity in women with a mechanical valve compared to bioprosthetic. Conclusions: Pregnancies in women with a prosthetic heart valve demonstrate an increased risk of an adverse outcome, for both mothers and babies, compared with pregnancies in the absence of heart valve prostheses. In this contemporary population, the risk was lower than previously reported.NHMRC 1001066, NHMRC 1021025, NHMRC 1062262, ARC FT120100069, Australian Heart Foundatio