Previously unreported variant of the rectus femoris muscle.

Although uncommon, variant muscular variations can occur related to the quadriceps femoris. Such variations might be encountered in the clinical setting so these should be documented. Here, we report three additional heads related to the rectus femoris muscle identified during routine dissection of the right thigh. To our knowledge, such a variation has not been previously reported.

Occupational asthma in teachers.

BACKGROUND: Work-related asthma symptoms are common in teachers and teaching assistants, there are few studies evaluating their causes. AIMS: To identify causes of occupational asthma in teachers and teaching assistants referred to the Birmingham Occupational Lung Disease clinic 2000-20 using evaluation of serial Peak Expiratory Flow (PEF) records. METHODS: Teachers and teaching assistants with possible occupational asthma were asked to record PEF 2-hourly at home and work for 4 weeks. Their records were evaluated with the Oasys programme. Those with a positive score for any of the three scores (area between curves (ABC), timepoint and Oasys score from discriminant analysis) were included. Repeat records were made as indicated to help identify the cause and the effects of remedial actions. RESULTS: Thirty-eight teachers or teaching assistants met the inclusion criteria with all three Oasys scores positive in 24, 2/3 scores in nine and 1/3 in five. The building was the likely cause in 17 (in new builds particularly acrylates from carpet adhesives and in old buildings mould and construction dust), bystander exposure to agents in the schools in 12 (cleaning agents, acrylates from photocopiers and chloramines from indoor pools) and materials used in the classroom in 9 (most commonly MDF in design and technology classes). We illustrate how the PEF records helped identify the cause. CONCLUSIONS: Oasys analysis of PEF records is a useful method of evaluating occupational asthma in teachers and identified difficult to confirm causes where successful remediation or redeployment was achieved.

Occupational asthma in office workers.

BACKGROUND: Office work has a relative perception of safety for the worker. Data from surveillance schemes and population-based epidemiological studies suggest that office work carries a low risk of occupational asthma (OA). Office workers are frequently used as comparators in studies of occupational exposure and respiratory disease. AIMS: We aimed to describe and illustrate our tertiary clinical experience of diagnosing OA in office workers. METHODS: We searched the Birmingham NHS Occupational Lung Disease Service clinical database for cases of occupational respiratory disease diagnosed between 2002 and 2020, caused by office work or in office workers. For patients with OA, we gathered existing data on demographics, diagnostic tests including Occupational Asthma SYStem (OASYS) analysis of serial peak expiratory flow and specific inhalational challenge, and employment outcome. We summarised data and displayed them alongside illustrative cases. RESULTS: There were 47 cases of OA (5% of all asthma) confirmed using OASYS analysis of PEFs in the majority. Sixty percent of cases occurred in healthcare, education and government sectors. The most frequently implicated causative exposures or agents were: indoor air (9), printing, copying and laminating (7), cleaning chemicals (4), mould and damp (4), and acrylic flooring and adhesives (4). Exposures were grouped into internal office environment, office ventilation-related and adjacent environment. CONCLUSIONS: Clinicians should be vigilant for exposures associated with OA in office workers who present with work-related symptoms, where respiratory sensitizing agents may be present. A structured approach to assessment of the workplace is recommended.

Occupational asthma caused by peracetic acid-hydrogen peroxide mixture.

BACKGROUND: Healthcare practice in the UK has moved away from using aldehyde disinfectants for the decontamination of endoscopes, in part due to the risk of respiratory sensitization. Peracetic acid (PAA) in combination with hydrogen peroxide (HP) is a commonly used alternative. AIM: We describe a case of occupational asthma (OA) diagnosed at our specialist occupational lung disease clinic and caused by occupational exposure to PAA-HP mixture, used as a disinfectant in an endoscope washer-disinfector machine. CASE REPORT: A 48-year-old man employed as a mycologist and environmental microbiologist at a Birmingham city hospital, UK, presented following an acute exposure to PAA-HP mixture causing lacrimation, burning optic pain and headache. He had also experienced symptoms suggestive of OA for the preceding 10 months, and the diagnosis was confirmed through OASYS analysis of serial peak expiratory flow measurements. He had been exposed to PAA-HP mixture whilst working in the endoscopy department for 12 months prior to the acute episode, and a subsequent specific inhalation challenge test was positive with a late asthmatic response to PAA-HP mixture. CONCLUSION: This case provides evidence for a sensitization mechanism in OA caused by PAA-HP mixture.

Cleaning agent occupational asthma in the West Midlands, UK: 2000-16.

BACKGROUND: Cleaning agents are now a common cause of occupational asthma (OA) worldwide. Irritant airway and sensitization mechanisms are implicated for a variety of old and new agents. AIMS: To describe the exposures responsible for cleaning agent OA diagnosed within a UK specialist occupational lung disease service between 2000 and 2016. METHODS: The Birmingham NHS Occupational Lung Disease Service clinical database was searched for cases of OA caused by cleaning agents, and data were gathered on age, gender, atopic status, smoking history, symptom onset, diagnostic investigations (including Occupational Asthma SYStem analysis of workplace serial peak expiratory flow measurements and specific inhalational challenge), proposed mechanism, industry, occupation and causative agent. RESULTS: Eighty patients with cleaning agent OA (77% female, 76% arising de novo) were identified. The median annual number of cases was 4 (interquartile range = 2-7). The commonest cleaning agents causing OA were chloramines (31%), glutaraldehyde (26%) and quaternary ammonium compounds (11%) and frequently implicated industries were healthcare (55%), education (18%) and leisure (8%). CONCLUSIONS: Certain cleaning agents in common usage, such as chlorine-releasing agents, quaternary ammonium compounds and aldehydes, are associated with sensitization and asthma. Their use alters over time, and this is particularly evident in UK healthcare where cleaning and decontamination practice and policy have changed. Vigilance for OA in workplaces such as hospitals, nursing homes, leisure centres and swimming pools, where these cleaning agents are regularly used, is therefore essential.

Emotional labour and aboriginal maternal infant care workers: The invisible load.

BACKGROUND: The term 'emotional labour' has been used to describe the competing demands on midwives to empathize with clients whilst maintaining a level of professional detachment. Previous research indicates that when individuals experience difficulty managing these emotions, burnout may result. Aboriginal health care workers often have roles with large emotional demands, as they are relied upon heavily to engage clients in care. However, the concept of emotional labour has received little attention in relation to this group. AIM: To explore potential sources of emotional labour for Aboriginal Maternal Infant Care workers in a maternity care program for Aboriginal women in South Australia. The program involves these workers providing care for women in partnership with midwives. METHODS: We employed a phenomenological approach. Thirty in-depth interviews were conducted with staff and clients of the program. Recorded interviews were transcribed and coded and emerging themes identified. FINDINGS: This workforce undertakes extensive emotional labour. Key sources include the cultural and family obligations they have to clients, complex social needs of many clients, and potential for community backlash when poor perinatal outcomes occur. A lack of respect for the role within the workplace further contributes to these experiences. CONCLUSION: This study found that the responsibilities inherent to the role as both cultural broker and carer create significant emotional labour for workers. Recommendations to address this and enhance the sustainability of this workforce include: recognition and valuing of emotional work by management and other staff, enhancing cultural awareness training, and building stress-relieving activities into the workplace.

Assisted reproductive technologies: a hierarchy of risks for conception, pregnancy outcomes and treatment decisions.

The use of assisted reproductive technologies (ART) for the treatment of infertility has grown exponentially over the last 20 years, and now accounts for 4% of all births in Australia, and over 1 m births annually around the globe. There is consistent reporting of increased risk of adverse perinatal outcomes and birth defects following infertility treatment. However, change in practice has been stymied by critical knowledge gaps with regards to (a) the relative contribution of patient and treatment factors to adverse outcomes, (b) the independent contribution of specific contemporary treatments and treatment combinations to outcomes, (c) the impact of innovations in laboratory and clinical practice on treatment success and observed risk and (d) changes over time in patient characteristics. Here we summarize key findings from the South Australian Birth Cohort, which is a whole-of-population cohort of over 300,000 births from 1986 to 2002. Relative to spontaneous conceptions, singletons from assisted conception were more likely to be stillborn [odds ratio (OR)=1.82; 95% confidence interval (CI) 1.34-2.48], while survivors as a group were comprehensively disadvantaged at birth, including lower birth weight (OR=2109 g; 95% CI 2129-289), very low birth weight (OR=2.74; 95% CI 2.19-3.43), very preterm birth (OR=2.30; 95% CI 1.82-2.90) and neonatal death (OR=2.04; 95% CI 1.27-3.26). Major birth defects, including cardiac, urogenital and musculoskeletal defects are doubled after fresh ICSI cycles, which is a particular concern as ICSI now accounts for 70% of all treatment cycles globally. Future study is needed to provide contemporary, precise evidence to inform patient and clinic decision making, and generate knowledge for future innovation in ART laboratory methods and clinical practice, thereby optimizing treatment and health outcomes while reducing adverse events.

Occupational asthma caused by acrylic compounds from SHIELD surveillance (1989-2014).

BACKGROUND: Acrylic monomers (acrylates), methacrylates and cyanoacrylates all cause asthma by respiratory sensitization. Occupational inhalation exposures occur across a variety of industries including health care and dental work, beauty, laboratory science, assembly and plastic moulding. AIMS: To examine notifications of occupational asthma caused by acrylic compounds from a UK-based regional surveillance scheme, in order to highlight prevalent exposures and trends in presentation. METHODS: Retrospective review of all cases reported to the SHIELD surveillance scheme for occupational asthma, West Midlands, UK between 1989 and 2014. Patient data were gathered on demographics, employment, asthma symptoms and diagnostic investigations including serum immunological testing, serial peak flow analysis and specific inhalation challenge tests. Descriptive statistics were used to illustrate worker characteristics and evidence for sensitization to acrylic compounds. RESULTS: There were 20 affected patients out of 1790 total cases of occupational asthma (1%); all cases were confirmed by OASYS (Occupational Asthma SYStem) analysis of serial peak flow measurements, with three additional positive specific inhalation challenge tests. Three out of 20 (15%) patients were current smokers and 11/20 (55%) were atopic. A variety of exposures and industries were implicated including: manufacturing, health care, beauty and printing and a novel presentation seen in teachers exposed to floor adhesives. CONCLUSIONS: This is the largest reported series of occupational asthma caused by acrylic compounds, which remain an important aetiological factor in this disease. Exposure occurs in a variety of industries, particularly in manufacturing and is seen with other, perhaps better recognized sensitizing agents such as isocyanates and epoxy resins.

Maternal factors and the risk of birth defects after IVF and ICSI: a whole of population cohort study.

OBJECTIVE: To assess the contribution of maternal factors to major birth defects after in vitro fertilisation (IVF), intracytoplasmic sperm injection (ICSI), and natural conception. DESIGN: Retrospective cohort study in South Australia for the period January 1986 to December 2002. SETTING: A whole of population study. POPULATION: A census of all IVF and ICSI linked to registries for births, pregnancy terminations, and birth defects (diagnosed before a child's fifth birthday). METHODS: Odds ratios (ORs) for birth defects were calculated among IVF, ICSI, and natural conceptions for maternal age, parity, pre-pregnancy BMI, smoking, pre-existing diseases, and conditions in pregnancy, with adjustment for confounding factors. MAIN OUTCOME MEASURES: Birth defects classified by International Classification of Diseases (ninth revision) and British Paediatric Association (ICD9-BPA) codes. RESULTS: There were 2211 IVF, 1399 ICSI, and 301 060 naturally conceived births. The unadjusted prevalence of any birth defect was 7.1, 9.9, and 5.7% in the IVF, ICSI, and natural conception groups, respectively. As expected, the risk of birth defects increased with maternal age among the natural conceptions. In contrast, for IVF and ICSI combined, relative to natural conceptions, births to women aged ≤29 years had a higher risk (adjusted odds ratio, aOR 1.42; 95% confidence interval, 95% CI 1.04-1.94), births to women aged 35-39 years had no difference in risk (aOR 1.01; 95% CI 0.74-1.37), and births to women aged ≥40 years had a lower risk of defects (aOR 0.45; 95% CI 0.22-0.92). Defects were also elevated for nulliparity, anaemia, and urinary tract infection in births after ICSI, but not after IVF. CONCLUSIONS: The usual age-birth defect relationship is reversed in births after IVF and ICSI, and the associations for other maternal factors and defects vary between IVF and ICSI. TWEETABLE ABSTRACT: Risk of birth defects in women over 40 years is lower after infertility treatment than for natural conceptions.

Spontaneous loss of a co-twin and the risk of birth defects after assisted conception.

The study of very early pregnancy loss is impractical in the general population, but possible amongst infertility patients receiving carefully monitored treatments. We examined the association between fetal loss and the risk of birth defects in the surviving co-twin in a retrospective cohort study of infertility patients within an infertility clinic in South Australia from January 1986 to December 2002, linked to population registries for births, terminations and birth defects. The study population consisted of a total of 5683 births. Births from singleton pregnancies without loss were compared with survivors from (1) pregnancies with an empty fetal sac at 6-8 weeks after embryo transfer, (2) fetal loss subsequent to 8-week ultrasound and (3) multiple pregnancy continuing to birth. Odds ratios (OR) for birth defects were calculated with adjustment for confounders. Amongst infertility patients, the prevalence of birth defects was 7.9% for all twin pregnancies without fetal loss compared with 14.6% in pregnancies in which there had been an empty sac at ultrasound, and 11.6% for pregnancies with fetal loss after 6-8 weeks. Compared with singleton pregnancies without loss, the presence of an empty sac was associated with an increased risk of any defect (OR=1.90, 95% confidence intervals (CI)=1.09-3.30) and with multiple defects (OR=2.87, 95% CI=1.31-6.28). Twin pregnancies continuing to birth without loss were not associated with an overall increased prevalence of defects. We conclude that the observed loss of a co-twin by 6-8 weeks of pregnancy is related to the risk of major birth defects in the survivor.

Core food intakes of Australian children aged 9-10 years: nutrients, daily servings and diet quality in a community cross-sectional sample.

BACKGROUND: The present study aimed to evaluate core food intakes in 9-10-year-old Australian children by considering adequacy of nutrient intakes, comparing servings of core food groups with Australian recommendations and scoring overall diet quality. METHODS: Children from an established community-based cohort study completed a semi-quantitative food frequency questionnaire. Daily intakes of energy, macronutrients, micronutrients, servings of core (i.e. nutrient-rich) foods and a diet quality index were calculated and compared with appropriate standards. Sex and socio-economic differences were examined. RESULTS: The 436 children participating were from low to high socio-economic status families. As a group, over half of the children met estimated average requirements for key macro- and micronutrients, with the exception of fibre (inadequate in 41% of boys and 24% of girls). Children obtained 55% of their daily energy from core foods. Most children had fewer than the recommended servings of vegetables (91%) and meat/alternatives (99.8%), whereas boys generally ate fewer servings of grains and cereals than recommended (87%), and girls ate fewer servings of dairy (83%). Diet quality scores indicated room for improvement (median score of 26 for boys and 25 for girls, out of a maximum of 73 points). CONCLUSIONS: As a group, a large proportion of children were able to meet their daily nutrient requirements. However, achieving this through noncore foods meant that diets were high in salt, saturated fat and sugar; more servings of core foods and greater dietary diversity would be preferable. These results suggest that families need more support to optimise dietary patterns of children in this age group.

Growth trajectories in early childhood, their relationship with antenatal and postnatal factors, and development of obesity by age 9 years: results from an Australian birth cohort study.

BACKGROUND: In an era where around one in four children in the United Kingdom, the United States, and Australia are overweight or obese, the development of obesity in early life needs to be better understood. We aimed to identify groups of children with distinct trajectories of growth in infancy and early childhood, to examine any association between these trajectories and body size at age 9, and to assess the relative influence of antenatal and postnatal exposures on growth trajectories. DESIGN: Prospective Australian birth cohort study. SUBJECTS AND METHODS: In total, 557 children with serial height and weight measurements from birth to 9 years were included in the study. Latent class growth models were used to derive distinct groups of growth trajectories from birth to age 3½ years. Multivariable logistic regression models were used to explore antenatal and postnatal predictors of growth trajectory groups, and multivariable linear and logistic regression models were used to examine the relationships between growth trajectory groups and body size at age 9 years. RESULTS: We identified four discrete growth trajectories from birth to age 3½ years, characterised as low, intermediate, high, or accelerating growth. Relative to the intermediate growth group, the low group had reduced z-body mass index (BMI) (-0.75 s.d.; 95% confidence interval (CI) -1.02, -0.47), and the high and accelerating groups were associated with increased body size at age 9 years (high: z-BMI 0.70 s.d.; 95% CI 0.49, 0.62; accelerating: z-BMI 1.64 s.d.; 95% CI 1.16, 2.11). Of the antenatal and postnatal exposures considered, the most important differentiating factor was maternal obesity in early pregnancy, associated with a near quadrupling of risk of membership of the accelerating growth trajectory group compared with the intermediate growth group (odds ratio (OR) 3.72; 95% CI 1.15, 12.05). CONCLUSIONS: Efforts to prevent childhood obesity may need to be embedded within population-wide strategies that also pay attention to healthy weight for women in their reproductive years.

Can serial PEF measurements separate occupational asthma from allergic alveolitis?

BACKGROUND: Occupational asthma commonly results in work-related changes in serial peak expiratory flow (PEF) measurements. Whether alveolitis can result in similar changes is unknown. AIMS: To identify differences and similarities of serial PEF between workers with occupational alveolitis and asthma seen during an outbreak investigation in a factory with metal-working fluid exposure. METHODS: Workers with respiratory symptoms and rest-day improvement were identified by questionnaire. Each was asked to measure PEF 8 times daily for 4 weeks at home and work. Alveolitis was subsequently diagnosed from a validated scoring system including radiological changes, carbon monoxide diffusing capacity, bronchoalveolar lavage and biopsy results. Occupational asthma was confirmed with a positive Oasys score >2.5 and a mean rest-work PEF >16 l/min from serial 2-hourly PEF measurements. The Oasys PEF plotter calculated differences between rest and workdays for mean PEF, diurnal variation and the scores were used to confirm an occupational effect (Oasys, area between curve and time point). Records were compared between the alveolitis group and the group with occupational asthma without alveolitis. RESULTS: Forty workers with occupational asthma and 16 with alveolitis had indistinguishable PEF changes on workdays in terms of magnitude (median reduction 18.5 and 16.1 l/min, respectively) and diurnal variation. Immediate reactions were more common with occupational asthma and late reactions more common with alveolitis. CONCLUSIONS: PEF responses to metal-working fluid aerosols do not distinguish occupational asthma from alveolitis except in timing. They can be used to identify the workplace as the cause of asthma and also alveolitis.

Twenty years of SHIELD: decreasing incidence of occupational asthma in the West Midlands, UK?

INTRODUCTION: Since 2000 a decline in the incidence of occupational asthma (OA) has been reported in the UK and Europe. We aimed to describe and account for trends in the incidence of OA in the West Midlands, UK using annual notification data from the SHIELD voluntary surveillance scheme over the period 1991-2011. METHODS: All notifications to the SHIELD database between January 1991 and December 2011 were identified, along with patients' demographic data, occupations, causative agents and confirmatory tests. Annual notifications were scaled to give an annual count per million workers, giving a measure of incidence, and also standardised against those of bakers' asthma. Non-parametric analyses were undertaken between annual incidence and time (years) for common causative agents using (1) a negative binomial regression univariate model and (2) a logistic regression model calculating annual reporting ORs. A step-change analysis was used to examine time points at which there were marked reductions in incidence. RESULTS: A decrease in annual incidence of OA was observed over the study period (incident rate ratio=0.945; 95% CI 0.933 to 0.957; p<0.0001), an effect that was lost after standardising for bakers' asthma. Decreases in incidence were seen for most common causative agents, with only cleaning product-related OA increasing over 21 years. Marked fall in incidence was seen in 2004 for isocyanates, and in 1995 for latex. Most notifications came from a regional specialist occupational lung disease unit, with notifications from other sites falling from 16 cases/million workers/annum in 1995 to 0 in 2004. CONCLUSIONS: Reporter fatigue and increasing under-recognition of OA are both factors which contribute to the apparent fall in incidence of OA in the West Midlands. There is a future need for interventions that enable health professionals to identify potential cases of OA in the workplace and in healthcare settings.

Maternal body size prior to pregnancy, gestational diabetes and weight gain: associations with insulin resistance in children at 9-10 years.

AIMS: To investigate whether maternal body size pre-pregnancy, gestational diabetes and weight gain are independently associated with subsequent insulin resistance in children; and to examine the potential mediating role of child's body size in any associations. METHODS: At 9-10 years, 443 children took part in a follow-up of a prospective cohort. Of those, 163 children elected to provide a fasting blood sample and child insulin resistance was estimated by homeostasis model assessment. Generalized linear models with log link function and Gaussian family were used to assess associations with antenatal exposures. Potential confounders were considered as well as the role of the child's size. RESULTS: Prior to pregnancy, 23% of mothers were overweight and another 17% obese. All women were screened for gestational diabetes, with 6% diagnosed. On average, women gained an estimated 14 kg during pregnancy. Gestational diabetes was positively associated with child insulin resistance. In addition, maternal pre-pregnancy body mass index (BMI) was associated with child insulin resistance in a non-linear manner: a positive, progressive association was observed until BMI of 30 kg/m² was reached, but not thereafter. Estimated gestational weight gain was not associated with child insulin resistance. These findings were not accounted for by size of the child at birth or at 9-10 years. CONCLUSIONS: Maternal body size prior to pregnancy is positively associated with increases in child insulin resistance, at least until the 'obese' category is reached. This is independent of gestational diabetes and not mediated by body size of the child, suggesting genetic and/or developmental programming origins.

Sleep disturbances in a community-based sample of women with polycystic ovary syndrome.

STUDY QUESTION: Is there an excess of sleep disturbances in women with polycystic ovary syndrome (PCOS) in a community-based sample? STUDY ANSWER: Sleep disturbances are almost twice as common in women with PCOS compared with women of similar age without PCOS, with the association slightly accounted for by body weight and, to a greater extent, by depressive symptoms. WHAT IS KNOWN ALREADY: There is an excess of sleep-disordered breathing in clinical samples of women with PCOS, after accounting for their profile of body weight. Poor sleep patterns increase insulin resistance and thus may exacerbate PCOS symptoms and longer-term risk of metabolic disease. STUDY DESIGN, SIZE, DURATION: A cross-sectional study of 724 women, comprising 74% of a cohort study established retrospectively when women were around age 30 years. PARTICIPANTS/MATERIALS, SETTING, METHODS: Comparisons were made between 87 women with PCOS, diagnosed using the Rotterdam criteria, and 637 women without this diagnosis in Adelaide, South Australia. Differences in sleep disturbances, assessed using a modified version of the Jenkins questionnaire, were investigated using ordered logistic regression. MAIN RESULTS AND THE ROLE OF CHANCE: Sleep disturbances were twice as common in women with PCOS compared with those without. Specifically, PCOS was associated with increasing occurrence of difficulty falling asleep (odds ratio (OR) 1.94, 95% confidence interval (CI) 1.28-2.95); this association was attenuated but still statistically significant after accounting for BMI and depressive symptoms. Increasing occurrence of difficulty maintaining sleep (OR 1.92 95% CI 1.12-3.31) was mediated by obesity and depressive symptoms, together. Other factors did not change these findings. LIMITATIONS, REASONS FOR CAUTION: The cross-sectional nature of the study means that the direction of associations between PCOS and sleep disturbances is unclear, although bi-directionality for the mediators is likely based on data in the wider literature. WIDER IMPLICATIONS OF THE FINDINGS: Our results indicate that assessment and management of both sleep and mental health problems in women with PCOS should be undertaken. Longitudinal data would be valuable to see how poor sleep affects longer-term health profiles.

Cobalt asthma in metalworkers from an automotive engine valve manufacturer.

BACKGROUND: Cobalt asthma has previously been described in cobalt production workers, diamond polishers and glassware manufacturers. AIMS: To describe a case series of occupational asthma (OA) due to cobalt, identified at the Birmingham Heartlands Occupational Lung Disease Unit, West Midlands, UK. METHODS: Cases of cobalt asthma from a West Midlands' manufacturer of automotive engine valves, diagnosed between 1996 and 2005, were identified from the SHIELD database of OA. Case note data on demographics, employment status, asthma symptoms and diagnostic tests, including spirometry, peak expiratory flow (PEF) measurements, skin prick testing (SPT) and specific inhalational challenge (SIC) tests to cobalt chloride, were gathered, and descriptive statistics used to illustrate the data. RESULTS: The natural history of presentations has been described in detail, as well as a case study of one of the affected workers. Fourteen metalworkers (86% male; mean age 44.9 years) were diagnosed with cobalt asthma between 1996 and 2005. Workers were principally stellite grinders, stellite welders or machine setter-operators. All workers had positive Occupational Asthma SYStem analyses of serial PEF measurements, and sensitization to cobalt chloride was demonstrated in nine workers, by SPT or SIC. CONCLUSIONS: We have described a series of 14 workers with cobalt asthma from the automotive manufacturing industry, with objective evidence for sensitization. Health care workers should remain vigilant for cobalt asthma in the automotive manufacturing industry.

Is precarious employment associated with women remaining childless until age 35 years? Results from an Australian birth cohort study.

STUDY QUESTION: Does time in casual employment (while not studying full time) affect the likelihood of a woman having a child by age 35? SUMMARY ANSWER: Duration of time spent in casual employment is associated with an increased likelihood of childlessness at age 35 years, irrespective of socio-economic background as indicated by educational level. WHAT IS KNOWN ALREADY: Precarious employment conditions have become increasingly prevalent in recent decades in Western countries. The relationship between precarious employment conditions and age at first childbirth has been examined in several European countries with varying results. STUDY DESIGN, SIZE, DURATION: A retrospective cross-sectional component (n = 663) was added to an existing study based on a cohort of women born during 1973-1975. An event history calendar instrument was used to obtain data regarding a range of life domains over a 20-year period. PARTICIPANTS/MATERIALS, SETTING, METHODS: Using data from the Life Journeys of Young Women Project carried out in Adelaide, South Australia, Cox proportional hazards models were applied to investigate the research questions. MAIN RESULTS AND THE ROLE OF CHANCE: The likelihood of childbirth by around age 35 was reduced for every year spent in casual employment, irrespective of socioeconomic status, partner's education and parents' birthplace. The likelihood was reduced by 8, 23 and 35% for 1, 3 and 5 years spent in casual employment, respectively. LIMITATIONS, REASONS FOR CAUTION: Women with longer employment histories (and greater age at first birth) had more opportunities for errors in recall, but it is unlikely that such errors were systematic and led to bias in the results. While we included variables reflecting partner's education and length of time with a live-in partner, partner's employment histories were not taken into account. WIDER IMPLICATIONS OF THE FINDINGS: Duration of time spent in casual employment is associated with an increased likelihood of childlessness at age 35 years, and this association is present across the spectrum of socioeconomic status. We suggest that upstream labour market reforms could be considered in order to reduce barriers to childbearing.