Improving practice in radiology: a quality-improvement project examining CT colonography patient dose and scanning technique.

AIM: To audit scanning technique and patient doses for computed tomography (CT) colonography (CTC) examinations in a large UK region and to identify opportunities for quality improvement. MATERIALS AND METHODS: Scanning technique and patient dose data were gathered for both contrast-enhanced and unenhanced CTC examinations from 33 imaging protocols across 27 scanners. Measurements of patient weight and effective diameter were also obtained. Imaging protocols were compared to identify technique differences between similar scanners. Scanner average doses were calculated and combined to generate regional diagnostic reference limits (DRLs) for both examinations. RESULTS: The regional DRLs for contrast-enhanced examinations were volume CT dose index (CTDIvol) of 11 and 5 mGy for the two scan phases (contrast-enhanced and either delayed phase or non-contrast enhanced respectively), and dose-length product (DLP) of 740 mGy·cm. For unenhanced examinations, these were 5 mGy and 450 mGy·cm. These are notably lower than the national DRLs of 11 mGy and 950 mGy·cm. Substantial differences in scan technique and doses on similar scanners were identified as areas for quality-improvement action. CONCLUSION: A regional CTC dose audit has demonstrated compliance with national DRLs but marked variation in practice between sites for the dose delivered to patients, notably when scanners of the same type were compared for the same indication. This study demonstrates that the national DRL is too high for current scanner technology and should be revised.

An economic evaluation of planned immediate versus delayed birth for preterm prelabour rupture of membranes: findings from the PPROMT randomised controlled trial.

OBJECTIVE: This study is an economic evaluation of immediate birth compared with expectant management in women with preterm prelabour rupture of the membranes near term (PPROMT). DESIGN: A cost-effectiveness analysis alongside the PPROMT randomised controlled trial. SETTING: Obstetric departments in 65 hospitals across 11 countries. POPULATION: Women with a singleton pregnancy with ruptured membranes between 34+0 and 36+6 weeks gestation. METHODS: Women were randomly allocated to immediate birth or expectant management. Costs to the health system were identified and valued. National hospital costing data from both the UK and Australia were used. Average cost per recruit in each arm was calculated and 95% confidence intervals were estimated using bootstrap re-sampling. Averages costs during antenatal care, delivery and postnatal care, and by country were estimated. MAIN OUTCOMES MEASURES: Total mean cost difference between immediate birth and expectant management arms of the trial. RESULTS: From 11 countries 923 women were randomised to immediate birth and 912 were randomised to expectant management. Total mean costs per recruit were £8852 for immediate birth and £8740 for expectant delivery resulting in a mean difference in costs of £112 (95% CI: -431 to 662). The expectant management arm had significantly higher antenatal costs, whereas the immediate birth arm had significantly higher delivery and neonatal costs. There was large variation between total mean costs by country. CONCLUSION: This economic evaluation found no evidence that expectant management was more or less costly than immediate birth. Outpatient management may offer opportunities for cost savings for those women with delayed delivery. TWEETABLE ABSTRACT: For women with preterm prelabour rupture of the membranes, the relative benefits and harms of immediate and expectant management should inform counselling as costs are similar.

Child pneumonia - focus on the Western Pacific Region.

Worldwide, pneumonia is the leading cause of death in infants and young children (aged <5 years). We provide an overview of the global pneumonia disease burden, as well as the aetiology and management practices in different parts of the world, with a specific focus on the WHO Western Pacific Region. In 2011, the Western Pacific region had an estimated 0.11 pneumonia episodes per child-year with 61,900 pneumonia-related deaths in children less than 5 years of age. The majority (>75%) of pneumonia deaths occurred in six countries; Cambodia, China, Laos, Papua New Guinea, the Philippines and Viet Nam. Historically Streptococcus pneumoniae and Haemophilus influenzae were the commonest causes of severe pneumonia and pneumonia-related deaths in young children, but this is changing with the introduction of highly effective conjugate vaccines and socio-economic development. The relative contribution of viruses and atypical bacteria appear to be increasing and traditional case management approaches may require revision to accommodate increased uptake of conjugated vaccines in the Western Pacific region. Careful consideration should be given to risk reduction strategies, enhanced vaccination coverage, improved management of hypoxaemia and antibiotic stewardship.

Risk factors for child pneumonia - focus on the Western Pacific Region.

Pneumonia is a major cause of disease and death in infants and young children (aged <5 years) globally, as it is in the World Health Organization Western Pacific region. A better understanding of the underlying risk factors associated with child pneumonia is important, since pragmatic primary prevention strategies are likely to achieve major reductions in pneumonia-associated morbidity and mortality in children. This review focuses on risk factors with high relevance to the Western Pacific region, including a lack of exclusive breastfeeding, cigarette smoke and air pollution exposure, malnutrition and conditions of poverty, as well as common co-morbidities. Case management and vaccination coverage have been considered elsewhere.

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.

High maternal iron status, dietary iron intake and iron supplement use in pregnancy and risk of gestational diabetes mellitus: a prospective study and systematic review.

AIM: High iron measured using dietary intake and biomarkers is associated with Type 2 diabetes. It is uncertain whether a similar association exists for gestational diabetes mellitus. The aim of this systematic review was to conduct a cohort study examining first trimester body iron stores and subsequent risk of gestational diabetes, and to include these findings in a systematic review of all studies examining the association between maternal iron status, iron intake (dietary and supplemental) and the risk of gestational diabetes. METHODS: Serum samples from women with first trimester screening were linked to birth and hospital records for data on maternal characteristics and gestational diabetes diagnosis. Blood was analysed for ferritin, soluble transferrin receptor and C-reactive protein. Associations between iron biomarkers and gestational diabetes were assessed using multivariate logistic regression. A systematic review and meta-analysis, registered with PROSPERO (CRD42014013663) included studies of all designs published in English from January 1995 to July 2015 that examined the association between iron and gestational diabetes and included an appropriate comparison group. RESULTS: Of 3776 women, 3.4% subsequently developed gestational diabetes. Adjusted analyses found increased odds of gestational diabetes for ferritin (OR 1.41; 95% CI 1.11, 1.78), but not for soluble transferrin receptor (OR 1.00; 95% CI 0.97, 1.03) per unit increase of the biomarker. Two trials of iron supplementation found no association with gestational diabetes. Increased risk of gestational diabetes was associated with higher levels of ferritin and serum iron and dietary haem iron intakes. CONCLUSIONS: Increased risk of gestational diabetes among women with high serum ferritin and iron levels and dietary haem iron intakes warrants further investigation.

Association between interpregnancy interval and future risk of maternal cardiovascular disease-a population-based record linkage study.

OBJECTIVE: To examine the associations between interpregnancy interval and later maternal cardiovascular disease (CVD) risk. DESIGN: Population-based record linkage study. SETTING: New South Wales, Australia, 1994-2011. POPULATION: 216 467 women having first and second liveborn singleton infants, excluding those with an existing or pregnancy-related CVD risk factor. METHODS: We linked birth records of mothers to the mothers' subsequent CVD (coronary heart disease, cerebrovascular events, and chronic heart failure) hospitalisation or death. Multivariable Cox proportional hazard regression was used to estimate adjusted hazard ratios (AHR) [95% confidence interval (CI)], accounting for maternal age, parity, socioeconomic status, and smoking during pregnancy. MAIN OUTCOME MEASURES: The first occurrence of a CVD hospitalisation or death after the second birth. RESULTS: In comparison with mothers with an interpregnancy interval of 18-23 months (reference category), the AHR among mothers with interpregnancy interval of <12 months was 1.56 (95% CI 1.18-2.07) and of 12-17 months was 1.13 (95% CI 0.84-1.51). The AHRs were 1.40 (95% CI 1.07-1.82), 1.87 (95% CI 1.21-2.89), and 3.41 (95% CI 1.07-10.91), corresponding to interpregnancy intervals of 24-59, 60-119, and ≥120 months, respectively. AHRs of specific CVD categories showed a similar pattern. CONCLUSIONS: Interpregnancy interval is associated with the risk of subsequent maternal CVD in a J-shaped fashion. The association is independent of the existing and pregnancy-related CVD risk factors analysed. Both short and long interpregnancy intervals can be used as risk markers to identify women with an elevated CVD risk later in life. TWEETABLE ABSTRACT: Interpregnancy interval is associated with the risk of subsequent maternal cardiovascular disease in a J-shaped fashion.

Inflammatory bowel disease in pregnancy: a population-based study of prevalence and pregnancy outcomes.

OBJECTIVE: To determine the prevalence of the inflammatory bowel diseases (IBD), ulcerative colitis (UC) and Crohn's disease (CD), in pregnant women and determine pregnancy and fetal/neonatal outcomes. DESIGN: Population-based cohort study. SETTING: New South Wales, Australia, 2001-11. POPULATION: A total of 630 742 women who delivered at ≥20 weeks of gestation. METHODS: Descriptive and multivariate regression analyses of perinatal data linked to hospital admission data. We compared birth outcomes of women with and without a documented diagnosis of IBD. MAIN OUTCOME MEASURES: Caesarean section, severe maternal morbidity, preterm birth <37 weeks of gestation, planned preterm birth, small-for-gestational-age (birthweight <10th centile), perinatal mortality (stillbirth/neonatal death ≤28 days). RESULTS: In all, 1960 women (0.31%) with IBD, who had 2781 births (1183 UC, 1287 CD and 311 IBD-indeterminate). Women with IBD were more likely than women without IBD to have a caesarean section [41.5 versus 28.2%, adjusted risk ratio (aRR) 1.38, 95% CI 1.31-1.45], severe maternal morbidity (2.6 versus 1.6%, aRR 1.54, 95% CI 1.17-2.03), preterm birth (9.7 versus 6.6%, aRR 1.47, 95% CI 1.30-1.66), planned preterm birth (5.3 versus 2.9%, aRR 1.74, 95% CI 1.47-2.07), and their infants to be small-for-gestational-age (9.7 versus 9.5%, aRR 1.19, 95% CI 1.04-1.36). There was no evidence of a difference in perinatal mortality. CONCLUSION: Pregnancy-associated IBD is more common than previously reported. Pregnancies complicated by IBD at or near the time of birth have significantly higher rates of adverse pregnancy outcomes than pregnancies of women without IBD. TWEETABLE ABSTRACT: Increased rates preterm birth and caesarean section in women with inflammatory bowel disease.

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.

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.

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.

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.

Change in smoking status during two consecutive pregnancies: a population-based cohort study.

OBJECTIVE: To investigate changes in tobacco smoking in two consecutive pregnancies and factors associated with the change. DESIGN: Population-based cohort study. SETTING: New South Wales, Australia, 2000-10. POPULATION: A total of 183,385 women having first and second singleton pregnancies. METHODS: Descriptive and multivariable logistic regression analyses of perinatal data linked to hospital admission data. MAIN OUTCOME MEASURES: Proportion of women smoking during their first pregnancy who quit by their second, and of women not smoking in their first pregnancy who did smoke during their second. RESULTS: Among 22,761 smokers in the first pregnancy, 33.5% had quit by their second. Among 160,624 non-smokers in their first pregnancy, 3.6% smoked during their second. Women who were aged ≥25 years, were married, born in a non-English speaking country, used private obstetric care, and lived in a socio-economically advantaged area were more likely to quit or less likely to start smoking in the second pregnancy. Smokers who had gestational hypertension (adjusted odds ratio [OR] 1.36, 95% confidence interval [95% CI] 1.23-1.51), a large-for-gestational-age infant (OR 1.66, 95% CI, 1.46-1.89), and a stillbirth (OR 1.44, 95% CI 1.06-1.94) were more likely to quit, whereas smokers whose infant was small-for-gestational-age (OR 0.65, 95% CI 0.60-0.70) or admitted to special care nursery (OR 0.87, 95% CI 0.81-0.94) were less likely to quit. Among non-smokers in the first pregnancy, the risk of smoking in the second pregnancy increased with late antenatal attendance (e.g. ≥26 weeks, OR 1.30, 95% CI 1.14-1.48), gestational diabetes (OR 1.25, 95% CI 1.07-1.45), preterm birth (e.g. spontaneous, OR 1.25, 95% CI 1.10-1.43), caesarean section (e.g. prelabour, OR 1.13, 95% CI 1.01-1.26), and infant small-for-gestational-age (OR 1.37, 95% CI 1.26-1.48) or required special care nursery (OR 1.14, 95% CI 1.06-1.23). Inter-pregnancy interval of ≥3 years was associated with either change in smoking status. CONCLUSIONS: Most smokers continue to smoke in their next pregnancy, even among those who experienced poor outcomes. Intensive interventions should be explored and offered to women at the highest risk.

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.

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.

Incidence and outcomes of pregnancy-associated cancer in Australia, 1994-2008: a population-based linkage study.

OBJECTIVE: To determine trends in pregnancy-associated cancer and associations between maternal cancer and pregnancy outcomes. DESIGN: Population-based cohort study. SETTING: New South Wales, Australia, 1994-2008. POPULATION: A total of 781 907 women and their 1 309 501 maternities. METHODS: Cancer and maternal information were obtained from linked cancer registry, birth and hospital records for the entire population. Generalised estimating equations with a logit link were used to examine associations between cancer risk factors and pregnancy outcomes. MAIN OUTCOME MEASURES: Incidence of pregnancy-associated cancer (diagnosis during pregnancy or within 12 months of delivery), maternal morbidities, preterm birth, and small- and large-for-gestational-age (LGA). RESULTS: A total of 1798 new cancer diagnoses were identified, including 499 during pregnancy and 1299 postpartum. From 1994 to 2007, the crude incidence rate of pregnancy-associated cancer increased from 112.3 to 191.5 per 100 000 maternities (P < 0.001), and only 14% of the increase was explained by increasing maternal age. Cancer diagnosis was more common than expected in women aged 15-44 years (observed-to-expected ratio 1.49; 95% CI 1.42-1.56). Cancers were predominantly melanoma (33.3%) and breast cancer (21.0%). Women with cancer diagnosed during pregnancy had high rates of labour induction (28.5%), caesarean section (40.0%) and planned preterm birth (19.7%). Novel findings included a cancer association with multiple pregnancies (adjusted odds ratio 1.52, 95% CI 1.13-2.05) and LGA (aOR 1.47, 95% CI 1.14-1.89). CONCLUSIONS: Pregnancy-associated cancers have increased, and this increase is only partially explained by increasing maternal age. Pregnancy increases women's interaction with health services and the possibility for diagnosis, but may also influence tumour growth.

Effectiveness of nifedipine tocolysis to facilitate external cephalic version: a systematic review.

BACKGROUND: The success rates of external cephalic version (ECV) are improved with the use of betamimetic tocolytics, but these drugs are associated with maternal side effects. OBJECTIVES: To critically evaluate the effectiveness and advantages, if any, of nifedipine as a tocolytic for ECV. SEARCH STRATEGY: We searched PubMed, OVID [Medline, all evidence-based medicine (EBM) reviews], Embase, the Cochrane clinical trials register and references therein. SELECTION CRITERIA: Randomised trials comparing nifedipine with placebo or another tocolytic agent among women with a singleton, term breech or transverse presentation. DATA COLLECTION AND ANALYSIS: Two reviewers evaluated search results and extracted data from eligible studies using a standard data extraction form. Primary outcomes were success rates of ECV and cephalic presentation at delivery. Pooled relative risks and 95% confidence intervals were calculated for comparable studies, and where similar outcomes were assessed. MAIN RESULTS: Three trials met the inclusion criteria. Two trials (n = 176) compared nifedipine with terbutaline and found lower rates of successful ECV among women receiving nifedipine, pooled risk ratio = 0.67 (95% CI 0.48-0.93, P = 0.016). One trial (n = 320) comparing nifedipine with placebo did not find any significant difference in ECV success rates (41.6% nifedipine versus 37.2% placebo, P = 0.43). Although minor side effects were slightly higher with nifedipine compared with placebo, there was no significant difference in the rate of adverse maternal or neonatal outcomes or maternal satisfaction between the nifedipine and terbutaline groups, and women in both groups showed a similar preference for oral administration (62% nifedipine and 71% terbutaline). AUTHORS' CONCLUSIONS: This review found no evidence to support the use of nifedipine for tocolysis to facilitate external cephalic version.

Trends in obstetric practices and meconium aspiration syndrome: a population-based study.

OBJECTIVE: To determine trends in the incidence of meconium aspiration syndrome (MAS), and maternal factors and obstetric practices associated with any decline. DESIGN: Population-based cohort study. SETTING: New South Wales (NSW), Australia. POPULATION: All 877 037 liveborn, singleton, term infants (≥ 37 weeks of gestation) in the period 1997-2007. METHODS: Data were obtained from birth records linked to the neonatal hospital discharge records. The birth data provided information on maternal and obstetric factors, whereas the outcome of interest, MAS, was obtained from hospital data on the neonates. Multivariable logistic regression was used to estimate the risk of MAS while simultaneously adjusting for the explanatory variables. MAIN OUTCOME MEASURES: The incidence of MAS per 1000 births, and odds ratios and 95% confidence intervals for maternal and obstetric factors for the development of MAS. RESULTS: The incidence of MAS declined significantly by 11.3% per annum (95% CI 10.1-12.6; P < 0.001) from 4.1 per 1000 births in 1997 to 1.3 per 1000 births in 2007. This was associated with a statistically significant decline in risk factors: maternal smoking (from 20 to 12%), gestational age (from 57 to 47% ≥ 40 weeks of gestation), delivery at small hospitals (from 15 to 9%) and infants with birthweight below the third percentile (from 3.3 to 2.4%). There were simultaneous statistically significant increases in practices that reduce the risk of MAS: labour inductions (from 22 to 27%) and birth by caesarean section, both elective, prior to 40 weeks of gestation (from 7.3 to 13.8%), and emergency (from 3.0 to 5.3% prior to 40 weeks of gestation, and from 5.1 to 6.7% at 40 weeks of gestation or later). CONCLUSIONS: The rate of MAS is declining, and this decline is associated with a reduction in maternal and pregnancy risk factors, and an increase in protective obstetric practices.

Amniotic fluid embolism in an Australian population-based cohort.

We utilised linked birth, hospital and death data for the entire population to determine the incidence of amniotic fluid embolism (AFE) and its mortality and morbidity. AFE diagnoses were identified from International Classification of Diseases, 10th Revision (ICD10)-coded hospital and/or death records with additional case definition criteria imposed. The AFE incidence was 3.3 per 100,000 (95% CI, 1.9-4.7), maternal fatality rate 35% (95% CI, 15-59) and perinatal mortality rate 32% (95% CI, 12-56). Newly identified risk factors included induction with vaginal prostaglandin and manual removal of the placenta, and survivors were at increased risk of cerebral infarction. Although two-thirds of women and infants survived, AFE also caused severe morbidity.

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.