Application of the case-specular method to two studies of wire codes and childhood cancers

Occupational Risk Factors and Hypertensive Disorders in Pregnancy: A Systematic Review

Hypertensive disorders in pregnancy (HDP), including gestational hypertension (GH) and preeclampsia (PE), characterize a major cause of maternal and prenatal morbidity and mortality. In this systematic review, we tested the hypothesis that occupational factors would impact the risk for HDP in pregnant workers. MEDLINE, Scopus, and Web of Knowledge databases were searched for studies published between database inception and 1 April 2021. All observational studies enrolling > 10 pregnant workers and published in English were included. Un-experimental, non-occupational human studies were excluded. Evidence was synthesized according to the risk for HDP development in employed women, eventually exposed to chemical, physical, biological and organizational risk factors. The evidence quality was assessed through the Newcastle–Ottawa scale. Out of 745 records identified, 27 were eligible. No definite conclusions could be extrapolated for the majority of the examined risk factors, while more homogenous data supported positive associations between job-strain and HDP risk. Limitations due to the lack of suitable characterizations of workplace exposure (i.e., doses, length, co-exposures) and possible interplay with personal issues should be deeply addressed. This may be helpful to better assess occupational risks for pregnant women and plan adequate measures of control to protect their health and that of their children.

The impact of occupational activities during pregnancy on pregnancy outcomes: a systematic review and metaanalysis

OBJECTIVE

Data: An increasing number of studies suggest that exposure to physically demanding work during pregnancy could be associated with increased risks of adverse pregnancy outcomes, but the results remain conflicted and inconclusive. The purpose of this study was to examine the influence of occupational activities during pregnancy on maternal and fetal health outcomes.

STUDY

Studies of all designs (except case studies and reviews) that contained information on the relevant population (women who engaged in paid work during pregnancy), occupational exposures (heavy lifting, prolonged standing, prolonged walking, prolonged bending, and heavy physical workload), comparator (no exposure to the listed physical work demands), and outcomes (preterm birth, low birthweight, small for gestational age, miscarriage, gestational hypertension, preeclampsia, gestational diabetes mellitus, stillbirth, and intrauterine growth restriction) were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

Five electronic databases and 3 gray literature sources were searched up to March 15, 2019.

RESULTS

Eighty observational studies (N=853,149) were included. Low-to-very low certainty evidence revealed that lifting objects ≥11 kg was associated with an increased odds ratio of miscarriage (odds ratio, 1.31; 95% confidence interval, 1.08-1.58; I²=79%), and preeclampsia (odds ratio, 1.35; 95% confidence interval, 1.07-1.71; I²=0%). Lifting objects for a combined weight of ≥100 kg per day was associated with an increased odds of preterm delivery (odds ratio, 1.31; 95% confidence interval, 1.11-1.56; I²=0%) and having a low birthweight neonate (odds ratio, 2.08; 95% confidence interval, 1.06-4.11; I²=73%). Prolonged standing was associated with increased odds of preterm delivery (odds ratio, 1.11; 95% confidence interval, 1.02-1.22; I²=30%) and having a small-for-gestational-age neonate (odds ratio, 1.17; 95% confidence interval, 1.01-1.35; I²=41%). A heavy physical workload was associated with increased odds of preterm delivery (odds ratio, 1.23; 95% confidence interval, 1.07-1.41; I²=32%) and having a low birthweight neonate (odds ratio, 1.79; 95% confidence interval, 1.11-2.87; I²=87%). All other associations were not statistically significant. Dose-response analysis showed women stand for >2.5 hours per day (vs no standing) had a 10% increase in the odds of having a preterm delivery.

CONCLUSION

Physically demanding work during pregnancy is associated with an increased risk of adverse pregnancy outcomes.

The impact of occupational shift work and working hours during pregnancy on health outcomes: a systematic review and meta-analysis

BACKGROUD

An increasing number of original studies suggest that exposure to shift work and long working hours during pregnancy could be associated with the risk of adverse pregnancy outcomes, but the results remain conflicting and inconclusive.

OBJECTIVE

To examine the influences of shift work and longer working hours during pregnancy on maternal and fetal health outcomes.

DATA SOURCES

Five electronic databases and 3 gray literature sources were searched up to March 15, 2019.

METHODS OF STUDY SELECTION

Studies of all designs (except case studies and reviews) were included, which contained information on the relevant population (women who engaged in paid work during pregnancy); exposure (rotating shift work [shifts change according to a set schedule], fixed night shift [typical working period is between 11:00 pm and 11:00 am] or longer working hours [>40 hours per week]);comparator (fixed day shift [typical working period is between 8:00 am and 6:00 pm] or standard working hours [≤40 hours per week]); and outcomes (preterm delivery, low birthweight [birthweight <2500 g], small for gestational age, miscarriage, gestational hypertension, preeclampsia, intrauterine growth restriction, stillbirth, and gestational diabetes mellitus).

TABULATION, INTEGRATION, AND RESULTS

From 3305 unique citations, 62 observational studies (196,989 women) were included. "Low" to "very low" certainty evidence from these studies revealed that working rotating shifts was associated with an increased odds of preterm delivery (odds ratio, 1.13; 95% confidence interval, 1.00-1.28, I² = 31%), an infant small for gestational age (odds ratio, 1.18, 95% confidence interval, 1.01-1.38, I² = 0%), preeclampsia (odds ratio, 1.75, 95% confidence interval, 1.01-3.01, I² = 75%), and gestational hypertension (odds ratio, 1.19, 95% confidence interval, 1.10-1.29, I² = 0%), compared to those who worked a fixed day shift. Working fixed night shifts was associated with an increased odds of preterm delivery (odds ratio, 1.21; 95% confidence interval, 1.03-1.42; I² = 36%) and miscarriage (odds ratio, 1.23; 95% confidence interval, 1.03-1.47; I² = 37%). Compared with standard hours, working longer hours was associated with an increased odds of miscarriage (odds ratio, 1.38; 95% confidence interval, 1.08-1.77; I² = 73%), preterm delivery (odds ratio, 1.21; 95% confidence interval, 1.11-1.33; I² = 30%), an infant of low birthweight (odds ratio, 1.43; 95% confidence interval, 1.11-1.84; I² = 0%), or an infant small for gestational age (odds ratio, 1.16, 95% confidence interval, 1.00-1.36, I² = 57%). Dose-response analysis showed that women working more than 55.5 hours (vs 40 hours) per week had a 10% increase in the odds of having a preterm delivery.

CONCLUSION

Pregnant women who work rotating shifts, fixed night shifts, or longer hours have an increased risk of adverse pregnancy outcomes.

Relation of outbursts of anger and the acute risk of placental abruption: A case-crossover study

BACKGROUND

Roughly, a fourth of all placental abruption cases have an acute aetiologic underpinning, but the causes of acute abruption are poorly understood. Studies indicate that symptoms of stress, depression, and anxiety during pregnancy may be associated with a higher risk of abruption.

OBJECTIVE

We examined the rate of abruption in the 2 hours immediately following outbursts of anger.

METHODS

In a multicentre case-crossover study, we interviewed 663 women diagnosed with placental abruption admitted to one of the seven Peruvian hospitals between January 2013 and August 2015. We asked women about outbursts of anger before symptom onset and compared this with their usual frequency of anger during the week before abruption.

RESULTS

The rate of abruption was 2.83-fold (95% confidence interval [CI] 1.85, 4.33) higher in the 2 hours following an outburst of anger compared with other times. The rate ratio (RR) was lower for women who completed technical school or university (RR 1.38, 95% CI 0.52, 3.69) compared to women with secondary school education or less (RR 3.73, 95% CI 2.32, 5.99, P-homogeneity = .07). There was no evidence that the association between anger episodes and abruption varied by hypertensive disorders of pregnancy (ie preeclampsia/ eclampsia) or antepartum depressive symptoms.

CONCLUSION

There was a higher rate of abruption in the 2 hours following outbursts of anger compared with other times, providing potential clues to the aetiologic mechanisms of abruption of acute onset.

Effect of Self-care Before and During Pregnancy to Prevention and Control Preeclampsia in High-risk Women

Our aims to examine the factors influencing self-care for the prevention and control of preeclampsia in high-risk women. The current study is a review where the researcher browsed the available databases such as PubMed, Cochrane, Medline, Google Scholar, Medscape, and relevant research published between 1980 and 2016 were studied. To search for articles, relevant Medical Subject Heading keywords were first determined (Self-care, preeclampsia, prevention.) A total of 350 related articles were first selected, and the findings of 70 were used to compile the present article. The results of the study were classified under two general categories, including (1). Counseling and screening strategies and (2) self-care strategies for the prevention and control of preeclampsia in high-risk women. Screening women at risk for preeclampsia include measures such as measuring their blood pressure, checking for signs of depression, testing for thrombosis, taking a history of preeclampsia, providing preconception counseling about the appropriate age, time of pregnancy, and encouraging weight loss in obese women. This review showed a positive relationship between knowledge about self-care for preeclampsia and its control. The factors influencing preeclampsia self-care include making lifestyle changes, having a healthy diet, learning stress management, performing exercise and physical activities, taking antioxidants, dietary supplements, and calcium and adherence to aspirin and heparin regimens. There is a positive relationship between preconception counseling, screening women at risk for preeclampsia, self-care for the prevention, and control of preeclampsia.

(1) Tweetable abstract self-care in high-risk women is strongly associated with prevention and control of preeclampsia.

Relationships among stress coping styles and pregnancy complications among women exposed to Hurricane Katrina

OBJECTIVE

To examine the relationship between maternal stress exposure, stress coping styles, and pregnancy complications.

DESIGN

Quantitative, cross-sectional, and prospective study.

SETTING

Tulane-Lakeside Hospital, New Orleans, LA and Women's Hospital, Baton Rouge, LA.

PARTICIPANTS

The study included 146 women (122 from New Orleans and 24 from Baton Rouge), who were pregnant during or immediately after Hurricane Katrina.

METHODS

Participants were interviewed regarding their hurricane experiences and perceived stress, and coping styles were assessed using the Brief COPE. Medical charts were also reviewed to obtain information about pregnancy outcomes. Logistic regression was performed to determine possible associations.

RESULTS

Hurricane exposure was significantly associated with induction of labor (adjusted odds ratio [aOR] = 1.39; 95% confidence interval [CI] [1.03, 1.86], P = .03) and current perceived stress (aOR = 1.50, CI [1.34, 1.99], P < .01). Stress perception significantly predisposed to pregnancy-induced hypertension (aOR = 1.16, CI [1.05, 1.30], P < .01) and gestational diabetes (aOR = 1.13, CI [1.02, 1.25], P = .03). Use of planning, acceptance, humor, instrumental support, and venting coping styles were associated with a significantly reduced occurrence of pregnancy complications (P < .05). Higher rates for gestational diabetes was found among women using the denial coping style (aOR = 2.25, CI [1.14, 4.45], P = .02).

CONCLUSION

Exposure to disaster-related stress may complicate pregnancy, whereas some coping styles may mitigate its effects. Further research should explore how coping styles may mitigate or exacerbate the effect of major stressors and how positive coping styles can be encouraged or augmented.

Physical activity, sedentary behavior and risk of hypertensive disorders of pregnancy in Hispanic women

OBJECTIVE

Prior studies of the association between physical activity and hypertensive disorders of pregnancy have been conflicting; the majority focused on leisure-time activity only, did not use physical activity questionnaires validated for pregnancy, and were conducted in primarily non-Hispanic white populations.

METHODS

We prospectively evaluated this association among 1240 Hispanic women in Proyecto Buena Salud. The Pregnancy Physical Activity Questionnaire, validated for use in pregnancy, was used to assess pre- and early pregnancy sports/exercise, household/caregiving, occupational and transportation activity. Diagnoses of hypertensive disorders of pregnancy were based on medical record abstraction and confirmed by the study obstetrician.

RESULTS

A total of 49 women (4.0%) were diagnosed with a hypertensive disorder of pregnancy, including 32 women (2.6%) with pre-eclampsia. In age-adjusted analyses, high levels of early pregnancy household/caregiving activity were associated with reduced risk of total hypertensive disorders (OR = 0.4, 95% CI 0.1-0.9) and pre-eclampsia (OR = 0.3, 95% CI 0.1-0.9) relative to low levels; however, these findings were no longer statistically significant in multivariable models. Pre-pregnancy activity and pattern of activity from pre- to early-pregnancy were not significantly associated with risk. Finally, sedentary behavior was not significantly associated with hypertensive disorders.

CONCLUSION

Findings from this prospective study of Hispanic women were consistent with those of prior prospective cohorts indicating that physical activity prior to and during early pregnancy does not significantly reduce risk of hypertensive disorders of pregnancy.

Loss of a close family member the year before or during pregnancy and the risk of placental abruption: a cohort study from Denmark and Sweden

BACKGROUND

Maternal stress during pregnancy is associated with a modestly increased risk of fetal growth restriction and pre-eclampsia. Since placental abruption shares similar pathophysiological mechanisms and risk factors with fetal growth restriction and pre-eclampsia, we hypothesized that maternal stress may be implicated in abruption risk. We investigated the association between maternal bereavement during pregnancy and placental abruption.

METHOD

We studied singleton births in Denmark (1978-2008) and Sweden (1973-2006) (n = 5,103,272). In nationwide registries, we obtained data on death of women's close family members (older children, siblings, parents, and partners), abruption and potential confounders.

RESULTS

A total of 30,312 (6/1000) pregnancies in the cohort were diagnosed with placental abruption. Among normotensive women, death of a child the year before or during pregnancy was associated with a 54% increased odds of abruption [95% confidence interval (CI) 1.30-1.82]; the increased odds were restricted to women who lost a child the year before or during the first trimester in pregnancy. In the group with chronic hypertension, death of a child the year before or in the first trimester of pregnancy was associated with eight-fold increased odds of abruption (odds ratio 8.17, 95% CI 3.17-21.10). Death of other relatives was not associated with abruption risk.

CONCLUSIONS

Loss of a child the year before or in the first trimester of pregnancy was associated with an increased risk of abruption, especially among women with chronic hypertension. Studies are needed to investigate the effect of less severe, but more frequent, sources of stress on placental abruption risk.

The combined association of psychosocial stress and chronic hypertension with preeclampsia

OBJECTIVE

This study aims to evaluate perceived lifetime stress, perceived stress during pregnancy, chronic hypertension, and their joint association with preeclampsia risk.

STUDY DESIGN

This study includes 4314 women who delivered a singleton live birth at the Boston Medical Center from October 1998 through February 2008. Chronic hypertension was defined as hypertension diagnosed before pregnancy. Information regarding lifetime stress and perceived stress during pregnancy was collected by questionnaire. Preeclampsia was diagnosed by clinical criteria.

RESULTS

Lifetime stress (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.6-2.9), perceived stress during pregnancy (OR, 1.7; 95% CI, 1.3-2.2), and chronic hypertension (OR, 10.4; 95% CI, 7.5-14.4) were each associated with an increased risk of preeclampsia. Compared to normotensive pregnancy with low lifetime stress, both normotensive pregnancy with high lifetime stress (OR, 2.1; 95% CI, 1.6-2.9) and pregnancy with chronic hypertension and low lifetime stress (OR, 10.2; 95% CI, 7.0-14.9) showed an increased risk of preeclampsia, while pregnancy with high lifetime stress and chronic hypertension yielded the highest risk of preeclampsia (OR, 21.3; 95% CI, 10.2-44.3). The joint association of perceived stress during pregnancy and chronic hypertension with preeclampsia was very similar to that of the joint association of lifetime stress and chronic hypertension with preeclampsia.

CONCLUSION

This finding indicates that high psychosocial stress and chronic hypertension can act in combination to increase the risk of preeclampsia up to 20-fold. This finding underscores the importance of efforts to prevent, screen, and manage chronic hypertension, along with those to reduce psychosocial stress, particularly among women with chronic hypertension.

Psychosocial stress related to the loss of a close relative the year before or during pregnancy and risk of preeclampsia

The role of stress in the pathogenesis of preeclampsia has only been investigated in a few studies, and the findings are not conclusive. We analyzed whether maternal bereavement shortly before or during pregnancy is associated with an increased risk of preeclampsia. We conducted a cohort study of singleton births in Denmark during 1978-2008 and in Sweden during 1973-2006 (n=4 122 490) by linking national population-based registers. Mothers were considered exposed to bereavement if they lost a parent, a sibling, a partner, or a child the year before or during pregnancy (n=124 553). The risk of preeclampsia was slightly increased for women who lost a close relative during the 6 months before conception (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.06-1.23) or during the first trimester of pregnancy (OR, 1.15; 95% CI, 1.03-1.29). Exposure during these periods tended to be more closely related to early preeclampsia (delivery before 34 weeks of gestation; OR, 1.37; 95% CI, 1.12-1.67) than to late preeclampsia (OR, 1.13; 95% CI, 1.06-1.20). The strongest association was observed between loss of a child and early preeclampsia when the exposure window was from 6 months before pregnancy until start of second trimester (OR, 4.03; 95% CI, 2.46-6.61). Our results related to timing of exposure suggest that severe stress may influence early placentation. However, the public health implications of our findings are limited in populations with a low prevalence of severe stress exposures.

Occupation as a risk factor for hypertensive disorders of pregnancy

BACKGROUND

Hypertensive disorders of pregnancy (HDP) are leading causes of morbidity and mortality and have been rising in incidence. Little is known about the effects of worker classifications on HDP. This large-scale study examines associations between occupational classifications and HDP.

METHODS

We examined 385,537 Texas Electronic Registrar Birth Registration 2005 birth certificates. Maternal occupations were coded using the Standard Occupational Classification (SOC). Crude and adjusted risks for HDP among working women within occupational groupings were analyzed and compared with risks of nonemployed women.

RESULTS

The risk of developing HDP varies across SOC occupational classifications. After controlling for known confounders, women employed in business, management, and the legal and social services, teaching, counseling, and healthcare professions are at higher risk for developing HDP than women employed in support industries, such as food preparation, housekeeping, cosmetic and personal care services, or nonemployed women. Women employed in computer, engineering, architectural, and scientific occupations also carry greater risks, although these increased risks do not affect women of normal weight.

CONCLUSIONS

Worker classification is an independent risk factor for HDP. Additional work must be done to examine the complex interactions among individual maternal genetics, biology, and physical and mental abilities and how they affect adverse health outcomes. Examining job stressors may shed light on these occupational variations and their potential HDP associations. Strategies to mitigate job stressors in the workplace should be considered.

Work-related maternal risk factors and the risk of pregnancy induced hypertension and preeclampsia during pregnancy. The Generation R Study

OBJECTIVE

To study the associations between physically demanding work and occupational exposure to chemicals and hypertensive disorders during pregnancy within a large birth cohort study, the Generation R Study.

METHODS

Associations between occupational characteristics and hypertensive disorders during pregnancy were studied in 4465 pregnant woman participating in a population-based prospective cohort study from early pregnancy onwards in the Netherlands (2002-2006). Mothers who filled out a questionnaire during mid-pregnancy (response 77% of enrolment), were included if they conducted paid employment, had a spontaneously conceived singleton live born pregnancy, and did not suffer from pre-existing hypertension (n = 4465). Questions on physical demanding work were obtained from the Dutch Musculoskeletal Questionnaire and concerned questions on manually handling loads of 25 kg or more, long periods of standing or walking, night shifts, and working hours. To assess occupational exposure to chemicals, job titles and task descriptions were linked to a job-exposure-matrix (JEM), an expert judgment on exposure to chemicals at the workplace. Information on hypertensive disorders during pregnancy was obtained from medical records.

RESULTS

We observed no consistent associations between any of the work related risk factors, such as long periods of standing or walking, heavy lifting, night shifts, and working hours, nor exposure to chemicals with hypertensive disorders during pregnancy.

CONCLUSION

This prospective birth cohort study suggests that there is no association of hypertensive disorders during pregnancy with physically demanding work or exposure to chemicals. However, the low prevalence of PIH and PE, combined with the low prevalence of occupational risk factors limit the power for inference and larger studies are needed to corroborate or refute these findings.

The contribution of maternal stress to preterm birth: issues and considerations

Preterm birth represents the most significant problem in maternal-child health, with maternal stress identified as a variable of interest. The effects of maternal stress on risk of preterm birth may vary as a function of context. This article focuses on select key issues and questions highlighting the need to develop a better understanding of which particular subgroups of pregnant women may be especially vulnerable to the potentially detrimental effects of maternal stress, and under what circumstances and at which stages of gestation. Issues related to the characterization and assessment of maternal stress and candidate biologic mechanisms are addressed.

Analysis of the S810L Point Mutation of the Mineralocorticoid Receptor in Patients with Pregnancy‐Induced Hypertension

OBJECTIVE

A missense mutation at codon 810 (Ser --> Leu) of the mineralocorticoid receptor was recently observed in a family with early manifestation of hypertension. Our objective was to determine if this mineralocorticoid receptor alterations is prevalent in patients with pregnancy-induced hypertension.

METHODS

Thirty-eight women with hypertension during pregnancy were tested for the mineralocorticoid receptor gene mutation. DNA was extracted out of blood leucocytes. PCR and automated DNA sequencing were used to analyze exon 6 for the S810L missense mutation. Anamnestical data concerning cardiovascular risk factors and family history were evaluated with a questionnaire. Pregnancy course and outcome were documented in all cases.

RESULTS

In 33 patients with pregnancy-induced hypertension and in five patients with exacerbation of preexisting hypertension in pregnancy no point mutations were found at codon 810 in exon 6.

CONCLUSIONS

Our data suggest that the S810L missense mutation of the mineralocorticoid receptor does not play a major role in the etiology of pregnancy-induced hypertension in a German /Turkish population.

Is psychosocial stress in first ongoing pregnancies associated with pre-eclampsia and gestational hypertension?

OBJECTIVE

Investigating the association of pre-eclampsia and gestational hypertension with psychosocial stress in the first half of pregnancy.

DESIGN

Prospective community-based cohort study.

SETTING

Amsterdam, The Netherlands.

POPULATION

Between January 2003 and March 2004, all pregnant Amsterdam women (n = 12 377) were invited to fill in a questionnaire with sociodemographic and psychosocial variables (response rate 67%). Only nulliparous women with a singleton pregnancy, who completed the questionnaire before 24 weeks, and delivered after 24 weeks, were included.

METHODS

A postpartum questionnaire was used to gather information on hypertension or proteinuria. If this questionnaire was not available, the national obstetric register was used for pregnancy outcome. Medical files were examined for women with hypertension and/or proteinuria to confirm the diagnosis of pre-eclampsia and gestational hypertension according to the International Society for the Study of Hypertension in Pregnancy guidelines. Psychosocial stress was defined as workstress (Work Experience and Appreciation Questionnaire partly based on the Job Content Instrument of Karasek et al.), anxiety (the State-Trait Anxiety Inventory), depression (Center for Epidemiological Studies Depression Scale) and pregnancy-related anxiety (PRAQ-R). The association of psychosocial stress with the incidence of pre-eclampsia and gestational hypertension was explored by multivariate analysis adjusted for sociodemographic and medical confounders.

MAIN OUTCOME MEASURES

Incidence of pre-eclampsia and gestational hypertension.

RESULTS

A total of 3679 women were included. The incidence of pre-eclampsia and gestational hypertension was 3.5 and 4.4%, respectively. Workstress, anxiety, pregnancy-related anxiety or depression had no effect on the incidence of pre-eclampsia or gestational hypertension.

CONCLUSION

Psychosocial stress in the first half of pregnancy does not influence the incidence of pre-eclampsia and gestational hypertension in nulliparous women.

Maternal Work and Birth Outcome Disparities

OBJECTIVES

We tested relations between aspects of maternal work and birth outcomes in a national sample and in subgroups known to experience disparities.

METHODS

Three indices of work attributes (Status and Recognition, Physical Demands, and Exposure to Conflict) were derived by factor analysis of variables extracted from the Department of Labor's O*Net database. The indices were linked to the National Longitudinal Survey of Youth using occupation codes for the primary jobs held by women who gave birth between 1979 and 2000 and worked during the quarter prior to birth (n = 3,386 births to n = 2,508 mothers). Multiple regression was used to model birth outcomes as functions of the work attribute indices, controlling for several measures of socioeconomic status and risk factors for adverse birth outcomes.

RESULTS

In the full sample, work-related Physical Demands were associated with lower average birthweight and increased odds of preterm birth while Status and Recognition was associated with higher average birthweight and lower odds of fetal growth restriction. In stratified models, Status and Recognition was associated with higher birth weight among women with low (versus high) income and with lower odds of preterm birth among women with low (versus high) education. Physical Demands were associated with higher rates of preterm birth among women with low (versus high) income and education and among African-American mothers (compared to Whites).

CONCLUSIONS

The work environment is an important predictor of healthy births. Relations between maternal work attributes and birth outcomes differ by race/ethnicity and socioeconomic status and according to the outcome under investigation. Further research with measures of work attributes specific to maternal work experiences is recommended to confirm our findings.

Environmental factors implicated in the causation of adverse pregnancy outcome

Adverse pregnancy outcome from environmental factors may include congenital anomalies, increased risk for miscarriage, preterm delivery, intrauterine growth restriction, and still birth. Apart from adverse pregnancy outcome, there may be effects on the other reproductive functions, like menstrual disorders and infertility. Environmental factors which have been implicated in adverse pregnancy outcome include smoking, video display terminals, anesthetic gases, antineoplastic drugs, and exposure to lead, selenium, and inorganic mercury. Among these, cigarette smoking during pregnancy has been the leading environmental factor for adverse pregnancy outcome. Cigarette smoking during pregnancy continues to be a significant public health concern. Maternal smoking during pregnancy has been associated with low birth weight (<2500 g). Mothers who smoke during pregnancy are twice as likely to give birth to low-birth weight infants. Similarly, air pollution, pesticide exposure, and stress have also been associated with low birth weight and preterm delivery. This review gives an overview of the importance of environmental factors in adverse pregnancy outcome.

Aromatherapy and massage for antenatal anxiety: Its effect on the fetus

Antenatal anxiety has been linked to maternal hypothalamic-pituitary-adrenal axis changes which can affect fetal development and may have lasting effects on the child's psychological development. Treatments for anxiety have hitherto focused on psychotherapy techniques or antidepressant drugs but these do not always effect long term improvement. Aromatherapy and massage have successfully been used to produce significantly greater improvement in reduction of anxiety. Midwives may highlight anxiety in some of the mothers in their care and can incorporate the holistic approach of aromatherapy and massage into their practice. However, further research is required to establish the efficacy and cost-effectiveness of aromatherapy and massage in the antenatal period.

Mothers in Stress: Consequences for the Offspring

No memories exist on one's time before birth. However, this does not imply that the developing fetus is not susceptible to external impulses. On the contrary, the fetus is extremely vulnerable e.g. to environmental challenges, and a wealth of data reveals that conditions in utero affect the health of the fetus before and after birth. Threats for the growing fetus include psychological challenges perceived by the mother, e.g. high levels of stress during pregnancy. However, stress experienced during pregnancy not only leads to pregnancy complications like miscarriage, pre-eclampsia, preterm parturition, low birth weight or major congenital malformations, stress also increases the risk of the child to develop diseases in the subsequent periods of life. This condition is termed fetal programming of adult disease. Programming agents seem to include growth factors, cytokines and hormones, all of which can be altered by stress. As a consequence, such 'stress-modified' systems of the offspring are more susceptible to environmental influences during later life, e.g. the development of atopic diseases upon exposure to antigens. The present review illuminates the complexity of stress perception on fetal programming focusing predominately on the onset of atopic diseases on the background of published evidence from immunology, endocrinology, neurobiology and neonatology.

Occupation and risk of cesarean section: study based on the perinatal survey of Baden-Württemberg, Germany

OBJECTIVES

The aim of this study was to assess the current influence of educational attainment and occupation on maternal obstetrical risk associated with cesarean section under the conditions of an industrialized country and provision of universal coverage.

MATERIALS AND METHODS

The perinatal survey data 1998-2001 of the German state of Baden-Württemberg were studied comparing method of delivery for the different occupational categories raised in the survey and the influence of antenatal care utilization. For statistical analysis chi square test, Fisher's exact test and chi square test for trends were used. Relative risks describe the risk for the exposed.

RESULTS

Cesarean section rate increased for all groups over the studied four years period. High rates of surgical deliveries were found for the categories "high salaried position" and "unskilled workers". Housewives, the largest group of pregnant women in Baden-Württemberg, delivered significantly less often by cesarean section (75% vaginal deliveries) than women of all other groups (66% vaginal deliveries on the average). In case of low utilization of antenatal care (<5 checks) risk of cesarean section and rate of complications (as blood loss >1,000 ml, hysterectomy) associated with cesarean section are significantly higher.

CONCLUSIONS

Differences in an individual woman's risk of having a cesarean section is, besides many other factors, associated with occupation. Antenatal care promotion should target the collective of unskilled workers, at special risk for insufficient use of prenatal care and high rate of cesarean delivery.

Social deprivation and poor access to care as risk factors for severe pre-eclampsia

OBJECTIVE

To estimate the associations between biomedical, social and health care factors and the occurrence of severe pre-eclampsia, eclampsia or HELLP syndrome.

STUDY DESIGN

A case-control study conducted in 14 of the 15 maternity hospitals of Brussels. Cases were all 99 women who delivered in these hospitals in 1996 and who had severe pre-eclampsia, eclampsia or HELLP syndrome. Controls were 200 women without these severe maternal conditions, randomly selected among women who delivered in the same hospitals during the same period. Crude odds ratios were computed and adjusted odds ratios were derived from logistic regression.

RESULTS

Indicators of social deprivation such as low educational level, poverty and illegal residence or asylum request, were strongly associated with the outcome in univariate analysis. So were African or Turkish ethnicity, obesity, chronic hypertension and primiparity. Logistic regression showed that no access to national health insurance and history of residence in another country were strongly and independently associated with the outcome (adjusted odds ratio = 4.0 (95% confidence interval 1.1, 14.0) and 3.7 (95% confidence interval 1.9, 7.3), respectively).

CONCLUSIONS

The burden of pre-eclampsia is concentrated in socially disadvantaged women. Health services should be more responsive to the specific needs of these women. Low access to health care may contribute to the occurrence of severe pre-eclampsia in our setting.

Stress-related preeclampsia: an evolutionary maladaptation in exaggerated stress during pregnancy?

The authors hypothesize that preeclampsia is a stress-related disease and an evolutionary maladaptation of exaggerated stress during human pregnancy. Epidemiologic studies show that relative risk for preeclampsia is increased in many stressful situations. Many risk factors for preeclampsia are stress-related. Low-stress situations, on the contrary, are protective. Stress in pregnancy corroborates all physiopathologic theories for preeclampsia; it does not contradict them. Animals exposed to intense stress show many characteristics of preeclampsia, and some animal models for human preeclampsia have been proposed. The stress-alarm reaction is protective for survival in animals. But the evolutionary maladaptation of this intense stress could lead to preeclampsia in humans.

[Validity of occupational stress and decision latitude on health in the National Population Health Survey of 1994-95]

Psychosocial environment at work is now considered a health determinant. The National Population Health Survey (NPHS) of 1994-95 is the first study in which psychological demands and decision latitude at work were measured in a random sample of the Canadian population. However, psychometric properties of the scales used in NPHS to measure these factors are not known. The objective of the present paper was to evaluate some validity parameters of the scales used in the NPHS by comparison to the original scales recommended by Karasek to measure these factors. Results of the current study support the validity of the decision latitude scale. However, validity of the psychological demand scale is more limited.

Life style, work and stress, and pregnancy outcome

Several environmental factors affect the fetus and thereby the outcome of pregnancy. Recent studies have confirmed a relation between stress and pregnancy outcome; furthermore they have indicated that biological measures of stress may predict risk of complications. Altered sex ratio may be an interesting way of measuring the effect of stress during pregnancy. Stress and work load during pregnancy seem to be related to time until conception and to becoming pregnant through assisted reproduction. Drinking large amounts of alcohol is hazardous, but drinking one drink per day appears to be safe. The effect of passive smoking continues to be a matter of debate.