Phthalates impact on the epigenetic factors contributed specifically by the father at fertilization.

BACKGROUND: Preconception exposure to phthalates such as the anti-androgenic dibutyl-phthalate (DBP) impacts both male and female reproduction, yet how this occurs largely remains unknown. Previously we defined a series of RNAs expressly provided by sperm at fertilization and separately, and in parallel, those that responded to high DBP exposure. Utilizing both populations of RNAs, we now begin to unravel the impact of high-DBP exposure on those RNAs specifically delivered by the father. RESULTS: Enrichment of RNAs altered by DBP exposure within the Molecular Signature Database highlighted cellular stress, cell cycle, apoptosis, DNA damage response, and gene regulation pathways. Overlap within each of these five pathways identified those RNAs that were specifically (≥ fivefold enriched) or primarily (≥ twofold enriched) provided as part of the paternal contribution compared to the oocyte at fertilization. Key RNAs consistently altered by DBP, including CAMTA2 and PSME4, were delivered by sperm reflective of these pathways. The majority (64/103) of overlapping enriched gene sets were related to gene regulation. Many of these RNAs (45 RNAs) corresponded to key interconnected CRREWs (Chromatin remodeler cofactors, RNA interactors, Readers, Erasers, and Writers). Modeling suggests that CUL2, PHF10, and SMARCC1 may coordinate and mechanistically modulate the phthalate response. CONCLUSIONS: Mediated through a CRREW regulatory network, the cell responded to exposure presenting stressed-induced changes in the cell cycle-DNA damage-apoptosis. Interestingly, the majority of these DBP-responsive epigenetic mediators' direct acetylation or deacetylation, impacting the sperm's cargo delivered at fertilization and that of the embryo.

Defining a study population using enhanced reporting of Aboriginality and the effects on study outcomes.

INTRODUCTION: The under-reporting of Aboriginal and Torres Strait Islander people on routinely collected health datasets has important implications for understanding the health of this population. By pooling available information on individuals' Aboriginal or Torres Strait Islander status from probabilistically linked datasets, methods have been developed to adjust for this under-reporting. OBJECTIVES: To explore different algorithms that enhance reporting of Aboriginal status in birth data to define a cohort of Aboriginal women, examine any differences between women recorded as Aboriginal and those assigned enhanced Aboriginal status, and assess the effects of using different reported populations to estimate within-group comparisons for Aboriginal people. METHODS: Three algorithms, with different levels of inclusiveness, were used to establish different study populations all of which aimed to include all singleton babies born to Aboriginal or Torres Strait Islander women residing in New South Wales, Australia between 2010 and 2014 and their mothers. The demographics of the four study populations were described and compared using frequencies and percentages. In order to assess the impact on research outcomes and conclusions of using study populations derived from different algorithms, estimates of the associations between smoking during pregnancy and selected perinatal outcomes were compared using rates and relative risks. RESULTS: Women included in the study population through enhanced reporting were older, less disadvantaged and more commonly resided in urban areas than those recorded as Aboriginal in the birth data. Although rates of smoking and some perinatal outcomes differed between the different study populations, the relative risks of each outcome comparing smoking and non-smoking Aboriginal mothers were very similar when estimated from each of the study populations. CONCLUSIONS: This work provides evidence that estimates of within-group relative risks are reliable regardless of the assumptions made for establishing the study population through the enhanced reporting of indigenous peoples.

Perinatal outcomes following bariatric surgery between a first and second pregnancy: a population data linkage study.

OBJECTIVES: To describe the population of women having bariatric surgery and compare the pregnancy outcomes for women having bariatric surgery with a non-bariatric surgery population having a first and second pregnancy. DESIGN: Population-based record linkage study. SETTING: New South Wales (NSW), Australia. POPULATION: All women aged 15-45 years with a hospital record in NSW (2002-2014) and all women giving birth in NSW (1994-2015; n = 1 606 737 women). METHODS: Pregnancy and birth outcomes were compared between first and second pregnancies using repeated-measures logistic regression and paired Student's t-tests. Bariatric and non-bariatric groups were also compared. MAIN OUTCOME MEASURES: Maternal diabetes, preterm birth (<37 weeks of gestation) and large for gestational age. RESULTS: There was a 13-fold increase in hospitalisations for primary bariatric surgery during 2002-2014. Compared with the general birthing population, women who had bariatric surgery experienced higher rates of hypertension, diabetes, and preterm birth. Among women who had bariatric surgery between a first and second pregnancy, there were reduced rates of hypertension (OR 0.39, 95% CI 0.29-0.53), spontaneous preterm birth (OR 0.37, 95% CI 0.16-0.86), infants that were large for gestational age (OR 0.63, 95% CI 0.44-0.88), and the admission of infants to a special care nursery or neonatal intensive care (OR 0.64, 95% CI 0.46-0.90) in the second pregnancy. Rates for small-for-gestational age and gestational diabetes following surgery were 8.3 and 11.4%, respectively CONCLUSIONS: Bariatric surgery between a first and second pregnancy was associated with reductions in obesity-related adverse pregnancy outcomes. Bariatric surgery performed for the management of obesity in accordance with current clinical criteria is associated with improved pregnancy outcomes in a subsequent pregnancy. TWEETABLE ABSTRACT: Bariatric surgery for obesity may improve pregnancy and birth outcomes in a subsequent pregnancy.

Using spatial metrics and surveys for the assessment of trans-boundary deforestation in protected areas of the Maya Mountain Massif: Belize-Guatemala border.

Understanding the trans-boundary deforestation history and patterns in protected areas along the Belize-Guatemala border is of regional and global importance. To assess deforestation history and patterns in our study area along a section of the Belize-Guatemala border, we incorporated multi-temporal deforestation rate analysis and spatial metrics with survey results. This multi-faceted approach provides spatial analysis with relevant insights from local stakeholders to better understand historic deforestation dynamics, spatial characteristics and human perspectives regarding the underlying causes thereof. During the study period 1991-2014, forest cover declined in Belize's protected areas: Vaca Forest Reserve 97.88%-87.62%, Chiquibul National Park 99.36%-92.12%, Caracol Archeological Reserve 99.47%-78.10% and Colombia River Forest Reserve 89.22%-78.38% respectively. A comparison of deforestation rates and spatial metrics indices indicated that between time periods 1991-1995 and 2012-2014 deforestation and fragmentation increased in protected areas. The major underlying causes, drivers, impacts, and barriers to bi-national collaboration and solutions of deforestation along the Belize-Guatemala border were identified by community leaders and stakeholders. The Mann-Whitney U test identified significant differences between leaders and stakeholders regarding the ranking of challenges faced by management organizations in the Maya Mountain Massif, except for the lack of assessment and quantification of deforestation (LD, SH: 18.67, 23.25, U = 148, p > 0.05). The survey results indicated that failure to integrate buffer communities, coordinate among managing organizations and establish strong bi-national collaboration has resulted in continued ecological and environmental degradation. The information provided by this research should aid managing organizations in their continued aim to implement effective deforestation mitigation strategies.

Association between interpregnancy interval and the risk of recurrent loss after a midtrimester loss.

STUDY QUESTION: After an initial midtrimester loss, is the interval to the next conception associated with the risk of a recurrent loss? SUMMARY ANSWER: Among women who had a pregnancy loss at 14-19 weeks gestation, conception at least 3 months after this initial loss was associated with a reduced risk of a recurrent loss. WHAT IS KNOWN ALREADY: A short interpregnancy interval (IPI) has been thought to increase risk but recent studies of pregnancy after a loss have found no effect; however, these studies have been based almost entirely on an initial first trimester (<14 weeks) loss. STUDY DESIGN, SIZE, DURATION: A retrospective cohort study drawing on over 997 000 linked birth and hospital records from New South Wales, Australia for 2003-2011. Index pregnancies were those of women who had a first recorded pregnancy loss of 14-23 weeks gestation (miscarriage, termination and perinatal death). The study population was 4290 women who conceived again within 2 years. PARTICIPANTS/MATERIALS, SETTING, METHODS: The index loss was categorized by subgroups: 14-19 weeks gestation versus 20-23 weeks, and by whether spontaneous or a termination. The primary outcome was any loss or perinatal death before 24 weeks in the subsequent pregnancy. MAIN RESULTS AND THE ROLE OF CHANCE: After a 14-19 weeks index loss, an IPI of ≤3 months had an increased rate of recurrent loss compared with an IPI of >9-12 months: 21.9% versus 11.3% (adjusted relative risk (aRR) = 2.02, 95% CI 1.44-2.83). For women who had a spontaneous index loss of 20-23 weeks, there was no evidence that a short IPI increased or decreased the risk of recurrent loss. For any gestational age group of index losses, an IPI of >18-24 months increased the risk of a recurrent loss; the risk was highest after a 20-23 weeks index loss (aRR = 2.15, 95% CI 1.18-3.91). LIMITATIONS, REASONS FOR CAUTION: We do not know how many cycles were required to achieve conception. Pregnancies resulting in early first trimester losses are unlikely to have resulted in hospitalization so would not have been identified. WIDER IMPLICATIONS OF THE FINDINGS: The risk of recurrent loss after an initial midtrimester loss may differ from the risk after an initial first trimester loss. STUDY FUNDING/COMPETING INTERESTS: This work was supported by an Australian National Health and Medical Research Council (NHMRC) Centre for Research Excellence Grant (1001066). C.L.R. is supported by an NHMRC Senior Research Fellowship (#APP1021025). J.B.F. is supported by an ARC Future Fellowship (#120100069). The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Prosthetic heart valves in pregnancy, outcomes for women and their babies: a systematic review and meta-analysis.

BACKGROUND: Historically, pregnancies among women with prosthetic heart valves have been associated with an increased incidence of adverse outcomes. OBJECTIVES: Systematic review to assess risk of adverse pregnancy outcomes among women with a prosthetic heart valve(s) over the last 20 years. SEARCH STRATEGY: Electronic literature search of Medline, The Cochrane Library, Cumulative Index to Nursing and Allied Health Literature and Embase to find recent studies. SELECTION CRITERIA: Studies of pregnant women with heart valve prostheses including trials, cohort studies and unselected case series. DATA COLLECTION AND ANALYSIS: Primary analysis calculated absolute risks and 95% confidence intervals (CI) for pregnancy outcomes using a random effects model. The Freeman-Tukey transformation was utilised in secondary analysis due to the large number of individual study outcomes with zero events. MAIN RESULTS: Eleven studies capturing 499 pregnancies among women with heart valve prostheses, including 256 mechanical and 59 bioprosthetic, were eligible for inclusion. Pooled estimate of maternal mortality was 1.2/100 pregnancies (95% CI 0.5-2.2), for mechanical valves subgroup 1.8/100 (95% CI 0.5-3.7) and bioprosthetic subgroup 0.7/100 (95% CI 0.1-4.5), overall pregnancy loss 20.8/100 pregnancies (95% CI 9.5-35.1), perinatal mortality 5.0/100 births (95%CI 1.8-9.8) and thromboembolism 9.3/100 pregnancies (95% CI 4.0-16.5). CONCLUSIONS: Women with heart valve prostheses experienced higher rates of adverse outcomes than expected in a general obstetric population; however, lower than previously reported. Women with bioprostheses had significantly fewer thromboembolic events compared to women with mechanical valves. Women should be counselled pre-pregnancy about risk of maternal death and pregnancy loss. Vigilant surveillance by a multidisciplinary team throughout the perinatal period remains warranted for these women and their infants. TWEETABLE ABSTRACT: Metaanalysis suggests improvement in #pregnancy outcomes among women with #heartvalveprostheses.

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

BACKGROUND: A lack of reproducible methods for classifying women having an induction of labour (IOL) has led to controversies regarding IOL and related maternal and perinatal health outcomes. OBJECTIVES: To evaluate articles that classify IOL and to develop a novel IOL classification system. SEARCH STRATEGY: Electronic searches using CINAHL, EMBASE, WEB of KNOWLEDGE, and reference lists. SELECTION CRITERIA: Two reviewers independently assessed studies that classified women having an IOL. DATA COLLECTION AND ANALYSIS: For the systematic review, data were extracted on study characteristics, quality, and results. Pre-specified criteria were used for evaluation. A multidisciplinary collaboration developed a new classification system using a clinically logical model and stakeholder feedback, demonstrating applicability in a population cohort of 909 702 maternities in New South Wales, Australia, over the period 2002-2011. MAIN RESULTS: All seven studies included in the systematic review categorised women according to the presence or absence of varying medical indications for IOL. Evaluation identified uncertainties or deficiencies across all studies, related to the criteria of total inclusivity, reproducibility, clinical utility, implementability, and data availability. A classification system of ten groups was developed based on parity, previous caesarean, gestational age, number, and presentation of the fetus. Nulliparous and parous women at full term were the largest groups (21.2 and 24.5%, respectively), and accounted for the highest proportion of all IOL (20.7 and 21.5%, respectively). AUTHOR'S CONCLUSIONS: Current methods of classifying women undertaking IOL based on medical indications are inadequate. We propose a classification system that has the attributes of simplicity and clarity, uses information that is readily and reliably collected, and enables the standard characterisation of populations of women having an IOL across and within jurisdictions.

Variation in hospital caesarean section rates and obstetric outcomes among nulliparae at term: a population-based cohort study.

OBJECTIVE: To explore the variation in hospital caesarean section (CS) rates for nulliparous women, to determine whether different case-mix, labour and delivery, and hospital factors can explain this variation and to examine the association between hospital CS 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 effect multilevel logistic regression models using linked hospital discharge and birth data. MAIN OUTCOME MEASURES: Prelabour and intrapartum CS rates following spontaneous labour or labour induction; maternal and neonatal severe morbidity rates. RESULTS: Of 67 239 nulliparous women, 4902 (7.3%) had a prelabour CS, 39 049 (58.1%) laboured spontaneously, and 23 288 (34.6%) had labour induced. Overall, there were 18 875 (28.1%) CSs, with labour inductions twice as likely to result in an intrapartum CS compared with women with a spontaneous onset of labour (34.0% versus 15.5%). After adjusting for differences in case-mix, labour and delivery, and hospital factors, the overall variation in CS rates decreased by 78% for prelabour CSs, 52% for intrapartum CSs following spontaneous labour and 9% following labour induction. Adjusting for labour and delivery practices increased the unexplained variation in intrapartum CSs. The adjusted rates of severe maternal and neonatal morbidity were not significantly different across CS rate quintile groups, except for women in spontaneous labour, where the hospitals in the lowest CS quintile had the lowest neonatal morbidity rate. CONCLUSIONS: Differences in clinical practice were substantial contributors to variation in intrapartum CS rates. Our findings suggest that CS rates in some hospitals could be lowered without adversely affect pregnancy outcomes.

What factors contribute to hospital variation in obstetric transfusion rates?

BACKGROUND AND OBJECTIVES: To explore variation in red blood cell transfusion rates between hospitals, and the extent to which this can be explained. A secondary objective was to assess whether hospital transfusion rates are associated with maternal morbidity. MATERIALS AND METHODS: Linked hospital discharge and birth data were used to identify births (n = 279 145) in hospitals with at least 10 deliveries per annum between 2008 and 2010 in New South Wales, Australia. To investigate transfusion rates, a series of random-effects multilevel logistic regression models were fitted, progressively adjusting for maternal, obstetric and hospital factors. Correlations between hospital transfusion and maternal, neonatal morbidity and readmission rates were assessed. RESULTS: Overall, the transfusion rate was 1.4% (hospital range 0.6-2.9) across 89 hospitals. Adjusting for maternal casemix reduced the variation between hospitals by 26%. Adjustment for obstetric interventions further reduced variation by 8% and a further 39% after adjustment for hospital type (range 1.1-2.0%). At a hospital level, high transfusion rates were moderately correlated with maternal morbidity (0.59, P = 0.01), but not with low Apgar scores (0.39, P = 0.08), or readmission rates (0.18, P = 0.29). CONCLUSION: Both casemix and practice differences contributed to the variation in transfusion rates between hospitals. The relationship between outcomes and transfusion rates was variable; however, low transfusion rates were not associated with worse outcomes.

Altered mental status and end organ damage associated with the use of gacyclidine: a case series.

INTRODUCTION: Over the past decade, there has been a sharp increase in the number of newly identified synthetic drugs. These new drugs are often derivatives of previously abused substances but have unpredictable toxicity. One of these drugs is gacyclidine, a derivative of phencyclidine (PCP). Gacyclidine has been studied as a neuroprotective agent in trauma and as a therapy of soman toxicity. There are no previous reports of its use as a drug of abuse. CASE REPORTS: During a two-month period in the summer of 2013, a series of patients with severe agitation and end-organ injury were identified in an urban academic Emergency Department (ED). A urine drug of abuse screen was performed on all patients, and serum samples were sent for comprehensive toxicology analysis. A total of five patients were identified as having agitation, rhabdomyolysis, and elevated troponin (Table 1). Three of the five patients reported use of methamphetamine, and all five patients had urine drug screens positive for amphetamine. Comprehensive serum analysis identified methamphetamine in three cases, cocaine metabolites in one case, and a potential untargeted match for gacyclidine in all five cases. No other drugs of abuse were identified. DISCUSSION: This is the first series of cases describing possible gacyclidine intoxication. The possible source of the gacyclidine is unknown but it may have been an adulterant in methamphetamine as all patients who were questioned reported methamphetamine use. These cases highlight the importance of screening for new drugs of abuse when patients present with atypical or severe symptoms. Gacyclidine has the potential to become a drug of abuse both by itself and in conjunction with other agents and toxicity from gacyclidine can be severe. It is the role of the medical toxicology field to identify new agents such as gacyclidine early and to attempt to educate the community on the dangers of these new drugs of abuse.

An 11-year review of bupropion insufflation exposures in adults reported to the California Poison Control System.

BACKGROUND: Seizures of both immediate and delayed onset after ingestion of bupropion SR and bupropion XL formulations are well documented, but are less well characterized after insufflation. Bupropion is crushed and insufflated to experience a high similar to that from amphetamines and cocaine. We sought to characterize the abuse of bupropion via insufflation in cases reported to the California Poison Control System (CPCS) and the incidence of seizures. METHODS: An 11-year (2002-2012) retrospective observational case series of insufflated bupropion exposures evaluated in a health care facility (HCF) were reviewed after searching our database for all bupropion insufflation exposures. Patients with coingestants, multiple exposure routes, or age less than 18 were excluded. Data included age, gender, estimated bupropion dose, occurrence of pre-HCF seizures, symptoms and vital signs reported to the CPCS, treatments, and adverse events that occurred until time of discharge. RESULTS: 74 cases were identified (1 excluded due to age, 5 excluded due to additional oral ingestion of bupropion, and 1 excluded due to being unable to follow). A total of 67 cases met inclusion criteria. The median age was 36 (range, 18-65) years. The total dose of bupropion insufflated was reported in 52 pts; median dose of 1500 (range, 100-9000) mg. Eighteen cases (27%) involved staggered or chronic exposures. Of the 67 patients, 20 (30%) experienced a seizure prior to arrival at the HCF. Of these, 19 patients (95%) presented with tachycardia. None of these patients had a second seizure in the emergency department. There were no major medical outcomes and no deaths. Of the 67 patients, 9 patients received benzodiazepines and 6 patients received single-dose activated charcoal. CONCLUSION: The abuse of bupropion by crushing and insufflating through the nose is uncommon (67/2270 or 3.0%) compared with that by oral bupropion exposures reported to CPCS. Seizures are common but are self-limited. Delayed seizures (more than 8 h after exposure) appear to be rare. Tachycardia is present in almost all patients who have seizures.

Occurrence and recurrence of diabetes in pregnancy.

AIMS: To determine occurrence and recurrence rates of gestational diabetes among women having at least two consecutive pregnancies. Risk factors for recurrence of gestational diabetes and rates of second/third pregnancy pre-existing diabetes mellitus were also assessed. METHODS: Population-based study using longitudinally linked hospital discharge and birth records (2001-2009) in NSW, Australia. Participants included women without a pre-existing diagnosis of Type 1 or Type 2 diabetes at time of first pregnancy and with at least a first and second birth. Factors associated with recurrence of gestational diabetes were examined using multivariate log-binomial models to adjust for correlation within mothers and estimate relative risks and 95% confidence intervals. RESULTS: First occurrence of gestational diabetes was 3.7% (5315/142 843) in the first pregnancy and 2.7% (3689/137 528) in the second pregnancy. The recurrence rate of gestational diabetes in a second consecutive pregnancy was 41.2%. Risk of pre-existing diabetes in a pregnancy subsequent to one with first occurrence of gestational diabetes was 2.2% and 2.0% in the second or third pregnancy, respectively. Among women with a diagnosis of gestational diabetes in the first pregnancy, independent predictors of gestational diabetes recurrence were maternal age ≥ 35 years, ethnicity (Middle East/North Africa and Asia), pregnancy hypertension, large for gestational age infant and preterm birth in the first pregnancy, longer inter-pregnancy birth interval and pregnancy hypertension and multiple pregnancy in the second pregnancy. CONCLUSIONS: Gestational diabetes in a previous pregnancy is a strong indicator of future risk and a useful clinical marker for identifying women at elevated risk in a subsequent pregnancy.

Blood leak alarm interference by hydoxocobalamin is hemodialysis machine dependent.

CONTEXT: Hydroxocobalamin has been reported to interfere with the blood leak alarm on hemodialysis machines making it difficult to use this treatment modality after hydroxocobalamin infusion. OBJECTIVE: The objective was to determine if this interference with hydroxocobalamin occurs across hemodialysis machines by different manufacturers. Additionally, we aimed to see if this represented a colorimetric interference alone or if it is the optical properties of hydroxocobalamin. MATERIALS AND METHODS: Hydroxocobalamin was reconstituted per package insert. Food coloring was added to 0.9% saline to create the colors of the visual spectrum. Optical properties of absorbance and transmittance were measured. Hydroxocobalamin and the saline solutions were infused into the Fresenius 2008K™ and the Gambro Phoenix X36™ machines. Times were recorded from the start of the machine until the solution finished or the alarm triggered. RESULTS: When evaluating the Gambro Phoenix X36™ machine and dialysis circuit; the alarm did not trigger. In contrast, the blood leak alarm on the Fresenius 2008K™ machine was tripped by both the red solution and hydoxocobalamin infused per the package insert. The alarm stopped the machine between 128 and 132 seconds for the red solution and between 30 and 35 seconds with the hydroxocobalamin. Membranes of the circuits where the alarm tripped were examined and remained intact without blood. Results were validated on different machines with new circuits. DISCUSSION: Hydroxocobalamin infusion per package insert and the red saline solution prepared with Red Dye 40 both triggered the blood leak alarm and stopped the Fresenius 2008K™ machine. However, this was not true for the Gambro Phoenix X36™ machine as the alarm never triggered. The interference with the Fresenius 2008K™ appears colorimetric due to normal saline with Red Dye 40 triggering the alarm. CONCLUSION: We alert physicians to become familiar with the properties of individual dialysis machines prior to use of hydroxocobalamin. When facing difficulties with hemodialysis after the administration of hydroxocobalamin, consider attempting with a different manufactures machine or model if available or contact the manufacturer directly.

Motor vehicle accidents during pregnancy: a population-based study.

This population-based cohort study of more than 600,000 Australian women describes the incidence of motor vehicle accidents (MVA) during pregnancy and the immediate and subsequent pregnancy outcomes. In this study, 3.5 women per 1000 maternities were admitted to hospital following an MVA. Immediate delivery was uncommon: 0.4% at <20 weeks of gestation and 3.5% at ≥ 20 weeks of gestation. Outcomes for those giving birth immediately were poor, with increased risk of antepartum haemorrhage, preterm birth, caesarean section and perinatal death. In contrast, women who remained undelivered following an MVA (96%) had similar pregnancy outcomes to women not involved in MVAs, and can be reassured.

Recurrence of breech presentation in consecutive pregnancies.

OBJECTIVE: To investigate the recurrence risk of breech presentation at term, and to assess the risk factors that contribute to its recurrence. DESIGN: Cohort study. SETTING: New South Wales, Australia. POPULATION: Women with their first two (n = 113 854) and first three (n = 21 690) consecutive singleton term pregnancies, in the period 1994-2002. METHODS: Descriptive statistics including rates, relative risks and adjusted relative risks, as determined from logistic regression and Poisson analyses. MAIN OUTCOME MEASURES: Rates and risks of occurrence and recurrence of breech presentation at birth in each pregnancy, and maternal and infant risk factors associated with breech recurrence. RESULTS: First-time breech presentation at term occurred in 4.2% of first pregnancy deliveries, 2.2% of second pregnancies and 1.9% of third pregnancies. The rate of breech recurrence in a second consecutive pregnancy was 9.9%, and in a third consecutive pregnancy (after two prior breech deliveries) was 27.5%. The relative risk of breech recurrence in a second pregnancy was 3.2 (95% CI 2.8-3.6), and in a third consecutive breech pregnancy was 13.9 (95% CI 8.8-22.1). First pregnancy factors associated with recurrence included placenta praevia [adjusted relative risk (aRR) 2.2; 95% CI 1.3-3.7], maternal diabetes (aRR 1.4; 95% CI 1.0-2.1) and a maternal age of > or =35 years (aRR 1.2; 95% CI 0.9-1.6). Second pregnancy factors included birth defects (aRR 2.5; 95% CI 1.4-4.2), placenta praevia (aRR 2.5; 95% CI 1.5-4.1) and a female infant (aRR 1.2; 95% CI 1.0-1.5). CONCLUSIONS: The increased recurrence risk of breech presentations suggests that women with a history of breech delivery should be closely monitored in the latter stages of pregnancy.

Trends in induction of labour, 1998-2007: a population-based study.

BACKGROUND: Increasing rates of induction have been reported in the UK, the USA, Canada and Australia since the early 1990s; however, there is a lack of population-based studies on trends and pharmacological management of induction of labour. AIMS: To determine population trends in induction of labour and predictors of failed induction (in caesarean section, specifically for failure to progress with cervix dilation < or =3 cm). METHODS: Trends in induction were determined for women in NSW who laboured at > or = 32 weeks from 1998 to 2007 (N = 739 904). To determine the predictors of failed induction, 92 359 deliveries of live singletons for whom linked birth and hospital data were available (2001-2005) were examined using logistic regression analysis. RESULTS: The rate of induction increased over the decade from 25.3 to 29.1%; however, among those induced with prostaglandin alone, it decreased from 33.5 to 23.8%. Oxytocin alone was the most commonly used labour induction agent overall (51%) and in most population subgroups. The predictors of failed induction in both nullipara and multipara included increasing maternal age, pre-term and post-term birth and the use of prostaglandin or mechanical methods of induction (neither oxytocin nor prostaglandin). CONCLUSIONS: The pharmacological agents used for induction of labour have changed over the past decade. An important area for future research is to investigate how the dosage of oxytocin and prostaglandin affects pregnancy outcomes.

The accuracy of reporting of general anaesthesia for childbirth: a validation study.

Administrative population health data, such as hospital discharge data, are a potentially valuable resource for determining anaesthesia and analgesia use in childbirth at a population level. However the reliability of general anaesthesia reporting is unknown. This study aimed to determine the accuracy of the reporting of peripartum general anaesthesia in single and linked population health data. Data from a statewide validation study of 1200 women provided the gold standard for delivery and postpartum general anaesthesia use. The validation data were merged with both the hospital discharge and birth databases. As both of these datasets collect information on general anaesthesia, it could be reported in one, both or neither database. Among the 1184 records available for review, 7.7% of women had a general anaesthetic during the birth admission, of which 6.2% were for delivery and 1.5% were for a postpartum procedure. Reporting sensitivities ranged from 26% to 97% and specificities 94% to 100%. Identifying general anaesthesia from either the birth or hospital data improved general anaesthesia ascertainment. Limiting analysis to caesarean sections resulted in very accurate identification of general anaesthesia for delivery (sensitivity 97.0%, specificity 99.8%) while limiting to vaginal births was moderately accurate for identifying postpartum general anaesthesia (sensitivity 73.2%, specificity 99.8%). General anaesthesia for delivery is reported with a high level of accuracy in birth and linked birth-hospital data, but not in hospital discharge data alone. Population health data are a reliable source for examining general anaesthesia for delivery.

Increased postpartum hemorrhage rates in Australia.

OBJECTIVE: To determine whether changes in risk factors for postpartum hemorrhage (PPH) over time are associated with a rise in postpartum hemorrhage rates. METHODS: Population-based study using linked hospital discharge and birth records from New South Wales, Australia for 752,374 women giving birth, 1994-2002. Analyses include a description of trends and regression analysis of risk factors for postpartum hemorrhage and comparison of predicted and observed rates of postpartum hemorrhage over time. RESULTS: Increasing proportions of women aged 35 years or older, born overseas, nulliparous, having cesarean births, having inductions and/or epidurals, postterm deliveries and large babies were evident. Observed postpartum hemorrhage rates increased from 4.7 to 6.0 per 100 births (P<0.001) while expected rates, adjusted for covariates, remained steady (P=0.28). CONCLUSION: Increases in postpartum hemorrhage are not explained by the changing risk profile of women. It may be that changes in management and/or reporting of postpartum hemorrhage have resulted in higher postpartum hemorrhage rates.

Comparison of selected reasons for hospitalization of children among children's/tertiary hospitals, Australia, 1996-97 and 1997-98.

OBJECTIVES: To describe the major characteristics of admissions to children's/tertiary hospitals (compared to other hospitals) and to compare characteristics of local and non-local admissions to specialist children's hospitals. METHODS: A cross-sectional analysis of a routinely collected data set of hospitalizations in Australia in 1996-97 and 1997-98. RESULTS: Hospital-specific proportions of asthma and bronchitis, tonsillectomy and/or adenoidectomy and gastroenteritis varied considerably. Multivariate analysis comparing the characteristics of admitted patients by locality showed that non-local admissions of patients with asthma and bronchitis and gastroenteritis to selected children's hospitals were significantly more likely to be Indigenous children and/or children who had been transferred from another hospital. Non-local admissions of tonsillectomy and/or adenoidectomy patients to selected hospitals were significantly more likely to be public patients. CONCLUSIONS: Differences in the characteristics of admitted patients to children's hospitals by locality raise issues about equality of access and availability of appropriate services for these children and their families.

Mutagenicity testing of nine herbicides and pesticides currently used in agriculture.

Nine herbicides and pesticides were tested for their mutagenicity using the Drosophila sex-linked recessive lethal mutation assay. These are Ambush, Treflan, Blazer, Roundup, 2,4-D Amine, Crossbow, Galecron, Pramitol, and Pondmaster. All of these are in wide use at present. Unlike adult feeding and injection assays, the larvae were allowed to grow in medium with the test chemical, thereby providing long and chronic exposure to the sensitive and dividing diploid cells, i.e., mitotically active spermatogonia and sensitive spermatocytes. All chemicals induced significant numbers of mutations in at least one of the cell types tested. Some of these compounds were found to be negative in earlier studies. An explanation for the difference in results is provided. It is probable that different germ cell stages and treatment regimens are suitable for different types of chemicals. larval treatment may still be valuable and can complement adult treatment in environmental mutagen testing.