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.

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.

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.

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.

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.

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.

Decreased prefrontal cortex dopamine activity following adolescent social defeat in male rats: role of dopamine D2 receptors

RATIONALE

Adverse social experience in adolescence causes reduced medial prefrontal cortex (mPFC) dopamine (DA) and associated behavioral deficits in early adulthood.

OBJECTIVE

This study aims to determine whether mPFC DA hypofunction following social stress is specific to adolescent experience and if this results from stress-induced DA D2 receptor activation.

MATERIALS AND METHODS

Male rats exposed to repeated social defeat during adolescence or adulthood had mPFC DA activity sampled 17 days later. Separate experiments used freely moving microdialysis to measure mPFC DA release in response to adolescent defeat exposure. At P40, 49 and 56 mPFC DA turnover was assessed to identify when DA activity decreased in relation to the adolescent defeat experience. Finally, nondefeated adolescent rats received repeated intra-mPFC infusions of the D2 receptor agonist quinpirole, while another adolescent group received intra-mPFC infusions of the D2 antagonist amisulpride before defeat exposure.

RESULTS

Long-term decreases or increases in mPFC DA turnover were observed following adolescent or adult defeat, respectively. Adolescent defeat exposure elicits sustained increases in mPFC DA release, and DA turnover remains elevated beyond the stress experience before declining to levels below normal at P56. Activation of mPFC D2 receptors in nondefeated adolescents decreases DA activity in a similar manner to that caused by adolescent defeat, while defeat-induced reductions in mPFC DA activity are prevented by D2 receptor blockade.

CONCLUSIONS

Both the developing and mature PFC DA systems are vulnerable to social stress, but only adolescent defeat causes DA hypofunction. This appears to result in part from stress-induced activation of mPFC D2 autoreceptors.

Effects of adolescent social defeat on adult amphetamine-induced locomotion and corticoaccumbal dopamine release in male rats

Maturation of mesocorticolimbic dopamine systems occurs during adolescence, and exposure to social stress during this period results in behavioral dysfunction including substance abuse disorders. Adult male rats exposed to repeated social defeat in adolescence exhibit reduced basal dopamine tissue content in the medial prefrontal cortex, altered dopamine tissue content in corticoaccumbal dopamine regions following acute amphetamine, and increased amphetamine conditioned place preference following repeated amphetamine treatment. Such changes may reflect altered amphetamine-induced extracellular dopamine release in the corticoaccumbal regions. Therefore, we used in vivo microdialysis to measure extracellular dopamine simultaneously within the medial prefrontal cortex and nucleus accumbens core of previously defeated rats and controls, in response to either acute or repeated (7 daily injections) of amphetamine (1.0 mg/kg). Locomotion responses to acute/repeated amphetamine were also assessed the day prior to taking dopamine measurements. Adolescent defeat potentiated adult locomotion responses to acute amphetamine, which was negatively correlated with attenuated amphetamine-induced dopamine release in the medial prefrontal cortex, but there was no difference in amphetamine-induced accumbal dopamine release. However, both locomotion and corticoaccumbal dopamine responses to repeated amphetamine were equivalent between previously defeated rats and controls. These data suggest adolescent defeat enhances behavioral responses to initial amphetamine exposure as a function of diminished prefrontal cortex dopamine activity, which may be sufficient to promote subsequently enhanced seeking of drug-associated cues. Interestingly, repeated amphetamine treatment appears to normalize amphetamine-elicited locomotion and cortical dopamine responses observed in adult rats exposed to adolescent social defeat, providing implications for treating stress-induced dopamine dysfunction.

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.

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.

First trimester screening of maternal placental protein 13 for predicting preeclampsia and small for gestational age: in-house study and systematic review

OBJECTIVE

To describe normative levels of PP13 in first trimester of pregnancy and determine the accuracy of PP13 in predicting preeclampsia and small for gestational age (SGA) infants.

METHODS

We measured PP13 in archived first trimester serum samples from an unselected maternal cohort of 2989 women. Associations of PP13 levels and diagnostic accuracy in predicting adverse pregnancy outcomes were assessed using multivariate logistic regression models. Due to inadequate number of cases we then conducted a systematic review and subsequent meta-analysis of predictive accuracy. Structured searches including all languages were completed in electronic databases and supplemented by cross-checking reference lists of relevant publications. Characteristics, data extraction and quality assessment of studies was conducted by independent assessors.

RESULTS

Overall, 2678 women were included in the in-house study with 71 (2.7%) preeclampsia cases, 5 (0.2%) early-onset preeclampsia (≤34 weeks) cases; and 191 (7.1%) and 41 (1.5%) infants SGA<10th and <3rd centile. Median (IQR) normative level of PP13 in unaffected pregnancies was 53.5 (37.7-71.8) pg/ml. The area under the receiver operating characteristic curve (AUC) for multivariate models was 0.72 (95%CI 0.66-0.78) for preeclampsia; 0.82 (95%CI 0.63-0.99) for early-onset preeclampsia; 0.73 (95%CI 0.69-0.77) for SGA<10th centile; and 0.83 (95%CI 0.78-0.88) for SGA<3rd centile. Eight studies were included in the systematic review, normative levels of PP13 were assessed in four studies but these were variable; and meta-analysis was performed on seven studies. Sensitivity rates of PP13 based on 5% fixed false positive rates were 24%, 45% and 26% for preeclampsia, for early-onset preeclampsia and SGA, respectively. There was no evidence of between-study heterogeneity.

CONCLUSIONS

First trimester PP13, in combination with maternal characteristics and other serum biomarkers was inadequate for screening purposes and predicting women at risk.

Diet quality and the influence of social and physical factors on food consumption and nutrient intake in materially deprived older people

BACKGROUND/OBJECTIVES

To investigate the influence of social and physical factors on diet quality in materially deprived (low income) older people in the United Kingdom.

SUBJECTS/METHODS

A diet quality index was obtained for 222 men and 440 women aged 65 and over living alone or with other adults of retirement age from the United Kingdom Low Income Diet and Nutrition Survey (2003-2005). The association between diet quality and social and physical factors was investigated by logistic regression analysis.

RESULTS

Analysis revealed several barriers to an adequate diet in the older low-income population. For both men and women, having the best quality diet was inversely associated with usually eating meals on one's lap as opposed to at the table (Adjusted odds ratio (ORs)=0.3, 95% confidence interval: 0.12-0.77 (men), 0.3, 0.17-0.56 (women)). For men, difficulty chewing was inversely associated with the best quality diet (OR=0.4; 0.13-0.99), whereas for women, current smoking and being 75 years or over were inversely associated with the best quality diet (OR=0.2; 0.06-0.42 and 0.5; 0.27-0.87, respectively); P value for all associations was <0.05.

CONCLUSIONS

Results suggest that the social setting is an important determinant of diet quality in this group and future studies should collect details on where and with whom meals are taken to fully investigate the extent of this influence.

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 ≥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.

Elicitation and punishment of intraspecies aggression by the same stimulus

Fighting responses were elicited in pairs of rats by shocks over a period of 46 days. During certain blocks of these days, "punishing" shocks were made contingent on the shock-elicited fights. Fighting frequency was reduced as a direct function of the intensity of the contingent shocks. Fighting frequency recovered completely when contingent shocks were removed.

Incidence and risk factors for pulmonary embolism in the postpartum period

SUMMARY BACKGROUND

Pregnancy and the postpartum period are times of hypercoagulability, increasing the risk of pulmonary embolism. Better quantification of risk factors can help target women who are most likely to benefit from postpartum thromboprophylaxis with heparin.

OBJECTIVES

To determine the incidence rate and timing of postpartum pulmonary embolism, and assess perinatal risk factors predictive of the event.

PATIENTS/METHODS

Antenatal, delivery and postpartum admission records of a cohort of 510 889 pregnancies were analysed. Pulmonary embolism was identified from ICD-10 codes at delivery, transfer or upon readmission at any time in the postpartum period.

RESULTS

Pulmonary embolism occurred in 375 women and was most common postpartum. The rate of postpartum pulmonary embolism without an antecedent thrombotic event was 0.45 per 1000 births. By the end of 4 weeks postpartum, the weekly rate approached the background rate of pulmonary embolism in the population. Although the Caesarean section rate rose significantly throughout the study period, and pulmonary embolism was more common following abdominal birth, the rate of pulmonary embolism following Caesarean birth fell. Regression modelling demonstrated that stillbirth (adjusted odds ratio [aOR] =5.97), lupus (aOR = 8.83) and transfusion of a coagulation product (aOR = 8.84) were most strongly associated with pulmonary embolism postpartum.

CONCLUSIONS

Pulmonary embolism most commonly occurs up to 4 weeks postpartum and following abdominal birth. Despite this the absolute event rate is low and a broadly inclusive risk factor approach to the use of pharmacological thromboprophylaxis will require many women to be exposed to heparin to prevent an embolic event.

Perinatal risk factors for early onset of Type 1 diabetes in a 2000-2005 birth cohort

AIMS

To examine perinatal risk factors for the onset of Type 1 diabetes before 6 years of age, in a 2000-2005 Australian birth cohort.

METHODS

Data from longitudinally linked delivery and hospital admission records (until June 2007) were analysed. Diabetes in mothers and children was identified from International Classification of Diseases 10 diagnosis codes in the hospital records.

RESULTS

There were 272 children admitted to hospital with a first diagnosis of diabetes out of 502 040 live births. Incidence for the infants born in 2000 was 16.0 per 100 000 person-years. Maternal Type 1 diabetes was a significant risk factor [crude relative risk (RR) 6.33], but maternal Type 2 diabetes and gestational diabetes were not significantly associated with diabetes in the child. Late preterm birth (34-36 weeks) (RR 1.64) and caesarean section (RR 1.30) increased the risk of a diabetes admission. Size-for-gestational-age was significantly associated with onset of diabetes (small-for-gestational age RR 0.48), but neither birth weight categories nor birth weight as a continuous variable were associated with risk of diabetes. Increasing maternal age was associated with an increased risk of diabetes in the child (RR 1.13 for each additional 5 years of age).

CONCLUSIONS

This study identified risk factors associated with onset of Type 1 diabetes before 6 years of age, in a recent birth cohort. Size-for-gestational-age had a consistent association with risk of early onset of Type 1 diabetes, small size being protective. Size-for-gestational-age measures should be preferred to birth weight thresholds when assessing risk of diabetes.

Removal of heavy metals from acid mine drainage (AMD) using coal fly ash, natural clinker and synthetic zeolites

Acid mine drainage (AMD) is a widespread environmental problem associated with both working and abandoned mining operations, resulting from the microbial oxidation of pyrite in presence of water and air, affording an acidic solution that contains toxic metal ions. The generation of AMD and release of dissolved heavy metals is an important concern facing the mining industry. The present study aimed at evaluating the use of low-cost sorbents like coal fly ash, natural clinker and synthetic zeolites to clean-up AMD generated at the Parys Mountain copper-lead-zinc deposit, Anglesey (North Wales), and to remove heavy metals and ammonium from AMD. pH played a very important role in the sorption/removal of the contaminants and a higher adsorbent ratio in the treatment of AMD promoted the increase of the pH, particularly using natural clinker-based faujasite (7.70-9.43) and the reduction of metal concentration. Na-phillipsite showed a lower efficiency as compared to that of faujasite. Selectivity of faujasite for metal removal was, in decreasing order, Fe>As>Pb>Zn>Cu>Ni>Cr. Based on these results, the use of these materials has the potential to provide improved methods for the treatment of AMD.

Outcomes of pregnancies in women with pre-gestational diabetes mellitus and gestational diabetes mellitus; a population-based study in New South Wales, Australia, 1998-2002

AIM

To determine population-based rates and outcomes of pre-gestational diabetes mellitus (pre-GDM) and gestational diabetes mellitus (GDM) in pregnancy.

METHODS

This was a cross-sectional study, using linked population databases, of all women, and their infants, discharged from hospital following birth in New South Wales (NSW) between 1 July 1998 and 31 December 2002. Women with, and infants exposed to pre-GDM or GDM were compared with those without diabetes mellitus for pregnancy characteristics and outcomes.

RESULTS

Women with a singleton pregnancy (n = 370,703) and their infants were included: 1248 women (0.3%) had pre-GDM and 17,128 (4.5%) had GDM. Of those women with pre-GDM, 57% had Type 1 diabetes, 20% had Type 2 diabetes and for 23% the type of diabetes was unknown. Major maternal morbidity or mortality was more common in women with pre-GDM (7.9%) [odds ratio (OR) 3.2, 95% confidence interval (CI) 2.6, 3.9] and in women with GDM (3.1%) (OR 1.2, 95% CI 1.1, 1.4) when compared with women without diabetes (2.6%). Major infant morbidity or mortality occurred more frequently in infants exposed to pre-GDM compared with no diabetes (13.6% vs. 3.1%) (OR 5.0, 95% CI 4.2, 5.8) and in infants exposed to GDM compared with no diabetes (3.2% vs. 2.3%) (OR 1.4, 95% CI 1.3, 1.5).

CONCLUSIONS

Pre-GDM and GDM continue to be associated with an increased risk of adverse maternal and neonatal outcomes; however, women with GDM have adverse outcomes less frequently. Rates of GDM and pre-GDM appear to be increasing over time. Clinicians should consider the potential for adverse outcomes, and arrange referral to appropriate services.

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.

Evaluation of a decision aid for women with breech presentation at term: a randomised controlled trial [ISRCTN14570598]

OBJECTIVES

To evaluate the effectiveness of a decision aid for women with a breech presentation compared with usual care.

DESIGN

Randomised controlled trial.

SETTING

Tertiary obstetric hospitals offering external cephalic version (ECV).

POPULATION

Women with a singleton pregnancy were diagnosed antenatally with a breech presentation at term, and were clinically eligible for ECV.

METHODS

Women were randomised to either receive a decision aid about the management options for breech presentation in addition to usual care or to receive usual care only with standard counselling from their usual pregnancy care provider. The decision aid comprised a 24-page booklet supplemented by a 30-minute audio-CD and worksheet that was designed for women to take home and review with a partner.

MAIN OUTCOME MEASURES

Decisional conflict (uncertainty), knowledge, anxiety and satisfaction with decision making, and were assessed using self-administered questionnaires.

RESULTS

Compared with usual care, women reviewing the decision aid experienced significantly lower decisional conflict (mean difference -8.92; 95% CI -13.18, -4.66) and increased knowledge (mean difference 8.40; 95% CI 3.10, 13.71), were more likely to feel that they had enough information to make a decision (RR 1.30; 95% CI 1.14, 1.47), had no increase in anxiety and reported greater satisfaction with decision making and overall experience of pregnancy and childbirth. In contrast, 19% of women in the usual care group reported they would have made a different decision about their care.

CONCLUSIONS

A decision aid is an effective and acceptable tool for pregnant women that provides an important adjunct to standard counselling for the management of breech presentation.

Test characteristics of placental location screening by transabdominal ultrasound at 18-20 weeks

OBJECTIVES

To determine the test characteristics of a second-trimester transabdominal fetal anomaly scan in screening for placenta previa.

PATIENTS AND METHODS

This was a case-control study carried out at a tertiary obstetric hospital involving 54 women (0.5% of the total number booked for antenatal care and delivery at the center) with clinically significant placenta previa at the time of delivery, and 168 randomly selected controls who attended for antenatal care and delivery in 2000-2003. Sensitivity, specificity and false positive rate of the placenta-os measurement in the second-trimester transabdominal fetal anomaly scan for identification of clinically significant placenta previa were assessed.

RESULTS

Women with placenta previa at delivery had significantly different second-trimester placenta-os measurements from those of controls (P < 0.0001). For women with placenta previa, the mean (standard deviation) placenta-os measurement was -0.96 cm (1.95) vs. 4.15 cm (1.77) for controls (P < 0.0001). Using the anomaly scan as a screening test for placenta previa with a placenta-os measurement cut-off point of < or = 2 cm, all cases of placenta previa should be identified, but 11.1% (95% CI, 7.1-14.8) of women without placenta previa would have false positive results. At cut-off points of 3 cm and 1.5 cm the false positive rates were 25.7% (95% CI, 18.8-30.2%) and 6.6% (95% CI, 3.8-9.6%), respectively, but at 1.5 cm 3.8% of cases would be missed.

CONCLUSIONS

The second-trimester transabdominal fetal anomaly scan is a useful screening test for placenta previa. However, because of false positives among the much larger population of women without placenta previa, we estimate that with a cut-off point of < or =2 cm, 23 women would have to be followed up to confirm one true placenta previa.

Discontinuation of epidural analgesia late in labour for reducing the adverse delivery outcomes associated with epidural analgesia

BACKGROUND

Although epidural analgesia provides the most effective labour analgesia, it is associated with some adverse obstetric consequences, including an increased risk of instrumental delivery. Many centres discontinue epidural analgesia late in labour to improve a woman's ability to push and reduce the rate of instrumental delivery.

OBJECTIVES

To assess the impact of discontinuing epidural analgesia late in labour on: i) rates of instrumental deliveries and other delivery outcomes; and ii) analgesia and satisfaction with labour care.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (1 September 2003).

SELECTION CRITERIA

Randomised controlled trials of epidurals discontinued late in labour compared with continuation of the same epidural protocol until birth, in women who receive an epidural for analgesia in the first stage of labour.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed study eligibility and quality and extracted the data. We analysed categorical data using relative risk (RR), and continuous data using weighted mean difference.

MAIN RESULTS

We identified six studies, of which five were included (462 participants). Three of these were high quality studies whilst the other two were judged to be of lower quality because placebo was not used and the method of randomisation not described. All studies used different epidural analgesia protocols (type of drug, dosage or method of administration). Overall, the reduction in instrumental delivery rate was not statistically significant (23% versus 28%, RR 0.84, 95% confidence interval (CI) 0.61 to 1.15) nor was there any statistically significant difference in rates of other delivery outcomes. The only statistically significant result was an increase in inadequate pain relief when the epidural was stopped (22% versus 6%, RR 3.68, 95% CI 1.99 to 6.80).

REVIEWERS' CONCLUSIONS

There is insufficient evidence to support the hypothesis that discontinuing epidural analgesia late in labour reduces the rate of instrumental delivery. There is evidence that it increases the rate of inadequate pain relief in the second stage of labour. The practice of discontinuing epidurals is widespread and the size of the reduction in instrumental delivery rate could be clinically important; therefore, we recommend a larger study than those included in this review be undertaken to determine whether this effect is real or has occurred by chance, and to provide stronger evidence about the safety aspects.

Trends in place of birth for preterm infants in New South Wales, 1992-2001

OBJECTIVE

To examine trends in preterm births, especially those less than 33 weeks gestation, occurring in perinatal centres in New South Wales (NSW) from 1992 to 2001.

METHODS

Population data were obtained from the NSW Midwives' Data Collection. Trends in the proportion of births in perinatal centres by gestation and by type of preterm birth (spontaneous or elective), and in Apgar scores and neonatal mortality were determined.

RESULTS

The preterm birth rate increased from 6.1% in 1992 to 6.7% in 2001. Factors contributing to the increase in preterm births were multiple births and elective preterm deliveries. Births less than 33 weeks gestation in perinatal centres increased from 76% to 83% and for multiple births from 77% to 87%. This coincided with a decrease in 1-minute Apgar scores less than 4 but no significant change in 5-minute Apgar scores or neonatal mortality.

CONCLUSIONS

Progress has been made towards the National Health and Medical Research Council guideline that births less than 33 weeks gestation occur in perinatal centres. Preterm births are increasing, creating greater demands for neonatal intensive care unit care and ventilation services.

Antibiotics for ureaplasma in the vagina in pregnancy

BACKGROUND

Preterm birth is a significant obstetric problem in high-income countries. Genital infection including ureaplasmas are suspected of playing a role in preterm birth and preterm rupture of the membranes. Antibiotics are used to treat women with preterm prelabour rupture of the membranes and results in prolongation of pregnancy and lowers the risks of maternal and neonatal infection. However, antibiotics may be beneficial earlier in pregnancy to eradicate potentially causative agents.

OBJECTIVES

The objective of this review is to assess whether antibiotic treatment of pregnant women with ureaplasma in the vagina reduces the incidence of preterm birth and other adverse pregnancy outcomes.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (April 2003).

SELECTION CRITERIA

All randomised controlled trials that compared any antibiotic regimen with placebo or no treatment in pregnant women with ureaplasma detected in the vagina.

DATA COLLECTION AND ANALYSIS

Three reviewers independently assessed eligibility and trial quality and extracted data.

MAIN RESULTS

One trial involving 1071 women was included. Of these, 644 randomly received antibiotic treatment (174 erythromycin estolate, 224 erythromycin sterate, and 246 clindamycin hydrochloride) and 427 received placebo. This trial did not report data on preterm birth. Incidence of low birthweight less than 2500 grams was only evaluated for erythromycin (combined) (n = 398 ) compared to placebo (n = 427) and there was no statistically significant difference between those treated and those not treated (relative risk (RR) 0.70, 95% confidence interval (CI) 0.46 to 1.07). In regards to side-effects sufficient to stop treatment, data were available for all women, and there were no statistically significant differences between any antibiotic (combined) and the placebo group (RR 1.25, 95% CI 0.85 to 1.85).

REVIEWER'S CONCLUSIONS

There is insufficient evidence to show whether giving antibiotics to women with ureaplasma in the vagina will prevent preterm birth.

Trends in twin births in New South Wales, Australia, 1990-1999

OBJECTIVE

To examine trends in gestational age and the mode of delivery of twins.

METHOD

All twin births in New South Wales, Australia from 1990 through 1999 were analyzed.

RESULTS

Twin births increased from 1922 (2.2%) in 1990 to 2522 (2.9%) in 1999. Twins born preterm (<37 weeks) increased from 40.8 to 48.8%. The increase in preterm twin births was associated with increases in induction of labor and cesareans before labor at 32-36 weeks. The rate of fetal deaths decreased by 49% and Apgar scores <4 at 5 min by 28%.

CONCLUSIONS

A greater than expected increase in preterm twins was largely explained by an increase in elective deliveries at 35-36 weeks' gestation. Increasing maternal age does not appear to have contributed to the increase in preterm twin births. Lower rates of fetal death and low Apgar scores were achieved seemingly at the price of delivering more infants before term.

Underreporting of Lyme disease by Connecticut physicians, 1992

To determine the magnitude of underreporting of Lyme disease, a random sample of Connecticut physicians was surveyed in 1993. The magnitude of underreporting was assessed by comparing physician estimates of Lyme disease diagnoses with reports of Lyme disease sent by physicians to the Connecticut Lyme disease surveillance system. Complete questionnaires were returned by 59 percent (412/698) of those surveyed. Of the 224 respondents who indicated that they had made a diagnosis of Lyme disease in 1992, only 56 (25 percent) reported a case of Lyme disease that year. Survey results suggested that, at best, only 16 percent of Lyme disease cases were reported in 1992. Physician underreporting of Lyme disease underestimates the public health impact of Lyme disease.

Differences and trends in obstetric interventions at term among urban and rural women in New South Wales: 1990-1997

The aim of this study was to compare the management of term births among rural and urban women, including the effect of indigenous status and out-of-area-birth for rural women. Data were obtained from the NSW Midwives Data Collection (MDC), on 619,298 women who gave birth to a live, singleton infant at term (37-45 weeks gestation) from 1 January 1990 to 31 December 1997. Compared with urban non-indigenous women, rural women and indigenous women had lower rates of obstetric interventions both before birth (induction of labour, planned Caesarean section and epidural) and at the time of birth (Caesarean after labour, instrumental delivery and episiotomy). This was especially true for rural women giving birth in the their local area. The differing pregnancy risk profile of rural women did not explain the differences in intervention rates but differences were partly explained by higher rates of epidural anaesthesia in urban areas.

Antenatal transfer of rural women to perinatal centres. High Risk Obstetric and Perinatal Advisory Working Group

The aim of this study was to describe antenatal transfers of rural women to perinatal centres, and among transferred women, to assess the use of selected evidence-based therapies and determine the predictors of preterm and imminent births. The clinical records of rural women antenatally transferred to perinatal centres in NSW and the ACT during 1997-1998 were reviewed. Of 453 rural antenatal transfers, 408 (90%) were emergency transfers. Increasing remoteness was associated with increased rates of antenatal transfer but not with a lower probability of giving birth. Of all transferred women, 64% delivered; 58% of preterm transfers delivered preterm and of those delivering preterm, 76% delivered within 7 days. Although the main reason for antenatal transfer was the possibility of preterm birth, women presenting with preterm contractions only were less likely to deliver preterm (OR = 0.2, 95% CI 0.1-0.4) or < or = 7 days (OR = 0.3, 95% CI 0.2-0.5) than women with any other presenting symptoms. The overall usage of effective interventions (antenatal steroids, antibiotics for PPROM and beta-mimetic tocolysis to delay birth) among antenatally transferred rural women was high, but there is room for increased uptake prior to transfer.

Rates for obstetric intervention among private and public patients in Australia: population based descriptive study

OBJECTIVE

To compare the risk profile of women receiving public and private obstetric care and to compare the rates of obstetric intervention among women at low risk in these groups.

DESIGN

Population based descriptive study.

SETTING

New South Wales, Australia.

SUBJECTS

All 171,157 women having a live baby during 1996 and 1997.

INTERVENTIONS

Epidural, augmentation or induction of labour, episiotomy, and births by forceps, vacuum, or caesarean section.

MAIN OUTCOME MEASURES

Risk profile of public and private patients, intervention rates, and the accumulation of interventions by both patient and hospital classification (public or private).

RESULTS

Overall, the frequency of women classified as low risk was similar (48%) among those choosing private obstetric care and those receiving standard care in a public hospital. Among low risk women, rates of obstetric intervention were highest in private patients in private hospitals, lowest in public patients, and generally intermediate for private patients in public hospitals. Among primiparas at low risk, 34% of private patients in private hospitals had a forceps or vacuum delivery compared with 17% of public patients. For multiparas the rates were 8% and 3% respectively. Private patients were significantly more likely to have interventions before birth (epidural, induction or augmentation) but this alone did not account for the increased interventions at birth, particularly the high rates of instrumental births.

CONCLUSIONS

Public patients have a lower chance of an instrumental delivery. Women should have equal access to quality maternity services, but information on the outcomes associated with the various models of care may influence their choices.

Early discharge and postnatal depression: a prospective cohort study

OBJECTIVES

To determine whether women discharged from hospital < or = 72 hours after childbirth (early discharge) were at greater risk of developing symptoms of postnatal depression during the following six months than those discharged later (late discharge), their reasons for early discharge and their level of postnatal support.

DESIGN AND SETTING

Population-based, prospective cohort study with questionnaires at Day 4, and at 8, 16 and 24 weeks postpartum, conducted at all birth sites in the Australian Capital Territory (ACT).

PARTICIPANTS

Women resident in the ACT giving birth to a live baby from March to October 1997.

MAIN OUTCOME MEASURE

A score > 12 on the Edinburgh Postnatal Depression Scale (EPDS).

RESULTS

1295 (70%) women consented to participate; 1193 (92%) were retained in the study to 24 weeks and, of these, 1182 returned all four questionnaires. Of the 1266 women for whom length-of-stay data were available, 467 (37%) were discharged early and 799 (63%) were discharged late. There were no significant differences between the proportion of women discharged early who ever scored > 12 on the EPDS during the six postpartum months and those discharged late (17% v. 20%), even after controlling for other risk factors (adjusted OR, 0.67; 95% CI, 0.44-1.01). Of women discharged early, 93% had at least one postnatal visit at home from a midwife and 81% were "very satisfied" with the care provided. Most women (96%) reported they had someone to help in practical ways.

CONCLUSIONS

Women discharged early after childbirth do not have an increased risk of developing symptoms of postnatal depression during the following six months.

The urban and rural divide for women giving birth in NSW, 1990-1997

OBJECTIVE

To examine trends in the pregnancy profile and outcomes of urban and rural women.

METHODS

Data were obtained from the NSW Midwives Data Collection on births in NSW, 1990-1997. Associations between place of residence (urban/rural) and maternal factors and pregnancy outcomes were examined, including changes over time.

RESULTS

From 1990 to 1997 there were 685,631 confinements in NSW and these mothers resided as follows: 76% metropolitan, 5% large rural centres, 8% small rural centres, 11% other rural areas and 1% remote areas. Rural mothers were more likely to be teenagers, multiparous, without a married or de facto partner, public patients and smokers. Births in rural areas declined, particularly among women aged 20-34 years. Infants born to mothers in remote communities were at increased odds of stillbirth and low Apgar scores (all women) and small-for-gestational- age (SGA) (Indigenous women only).

CONCLUSIONS

The profile of pregnant women in rural NSW is different from their urban counterparts and is consistent with relative socioeconomic disadvantage and possibly suboptimal maternity services in some areas. While increased risk of SGA is associated with environmental factors such as smoking and nutrition, the reasons the increased risk of stillbirth are unclear. Although there does not appear to be an increase d risk of preterm birth for rural women this may be masked by transfer of high risk pregnancies interstate.

IMPLICATIONS

Maternity services need to be available and accessible to all rural women with targeting of interventions known to reduce low birthweight and perinatal death.

Term breech birth in New South Wales, 1990-1997

Data on 636,708 women delivering a singleton infant of gestational age > or =37 weeks in NSW from 1 January 1990 to 31 December 1997 were used to examine trends in breech births at term and the mode of delivery. From 1990 to 1997, although the crude rate of breech births at term remained stable at 3.4%, the adjusted odds ratio for breech birth compared with cephalic birth decreased over time. Among live breech births, the crude rate of vaginal breech birth declined from 29.4% to 19.7%, with an attendant increase in elective Caesarean sections from 49.1% to 58.4%. Most of this increase was at 38 and 39 weeks gestation. There was no change in the perinatal mortality rate among breech births during the study period. Despite increasing maternal age, the adjusted odds of a breech birth at term decreased over time. This could be due to offsetting factors, such as increased use of external cephalic version. If the decrease in vaginal breech birth continues, it may lead to the skills for this procedure being lost.

Small fetal size: a risk factor for breech birth at term

OBJECTIVE

To examine fetal size as a risk factor for breech birth at term.

METHODS

Singleton breech or cephalic births of gestational age > or = 37 weeks in New South Wales (NSW), Australia from 1990 to 1996 were analyzed. Birthweight percentile was used as a measure of fetal size at the time of birth. Factors associated with breech birth at term were analyzed using logistic regression.

RESULTS

There were 18914 singleton breech and 540164 cephalic births in the study period. The important independent predictors of breech birth at term were advancing maternal age, primiparity, female sex and small size for gestational age. Infants < 10th percentile had an adjusted odds ratio of 1.33 (95% CI 1.28-1.38) for breech birth at term compared with 25th-75th percentile infants.

CONCLUSIONS

Breech birth at term was associated with smaller fetal size for gestational age. This was shown directly through an association with birthweight-for-gestational-age percentiles and indirectly through association with female sex, primiparous birth and congenital anomalies.

Trends in births at and beyond term: evidence of a change?

OBJECTIVE

To examine trends in the distribution of births at and beyond term in New South Wales and in particular, to determine whether any changes are associated with changes in the obstetric practices of induction and elective caesarean section.

DESIGN

Cross-sectional analytic study.

SETTING

New South Wales, Australia.

POPULATION

All 540,162 women delivering a singleton cephalic-presenting infant of gestational age > or = 37 weeks from 1 January 1990 to 31 December 1996.

METHODS

Data were obtained from the New South Wales midwives data collection, a population-based surveillance system covering all births in New South Wales. The data were analysed to examine changes over time and associations between gestational age, maternal factors and onset of labour.

MAIN OUTCOME MEASURES

Induction of labour and elective caesarean section rates.

RESULTS

From 1990 to 1996 there was a significant decrease in births reported as 40 weeks of gestation, from 35,670 (46.3%) to 30,651 (40.3%). These declines were offset by significant increases in births at 38 and 39 weeks. Births > or = 42 weeks declined from 3321 (4.6%) to 2132 (2.8%). The decline in prolonged pregnancies was associated with increasing induction rates at 41 weeks. The re-distribution of some births from 40 to 38-39 weeks was associated with increasing rates of elective caesarean sections and induction at 38 and 39 weeks, and increasing maternal age.

CONCLUSIONS

Clinicians appear to be implementing the recommendations of randomised controlled trials to offer induction after 41 weeks of gestation. However the trend of performing elective caesarean sections at earlier gestational ages may be unnecessarily putting some infants at increased risk of respiratory morbidity.

Listeria awareness among new mothers in Western Australia

OBJECTIVE

To assess awareness, knowledge and behaviour relating to Listeria among recent mothers (12 weeks post-partum) in Western Australia and determine the usefulness of a Listeria information pamphlet.

METHOD

A postal survey of a random 10% sample of Western Australian mothers whose babies were born between 1 January and 13 April 1997.

RESULTS

Of the 680 women surveyed, 509 (75%) responded and 451 (89%) respondents had heard of Listeria. The 11% who had not heard of Listeria had higher odds of living in a rural area, speaking a foreign language at home, having less formal education, being younger, having had an unplanned pregnancy, and having not taken folic acid supplements. Respondents who had seen the Listeria pamphlet had greater odds of correctly identifying foods at risk of Listeria. Of the women who had heard of Listeria, 90% had avoided certain foods during their pregnancy. Risk factors for not changing eating behaviour were similar to those for not having heard of Listeria.

CONCLUSIONS

Factors associated with not having heard of Listeria, not having seen the pamphlet and not having changed behaviour were similar, suggesting that there may be a group of women who are less likely to be aware of Listeria or other health issues and/or may be resistant to health-related behaviour changes.

IMPLICATIONS

The Listeria pamphlet is an effective medium for educating pregnant women about Listeria. Rural, young, single and non-English speaking background women may require a different or supplementary approach.