Antenatal risk factors, cytokines and the development of atopic disease in early childhood.

Atopic diseases are complex entities influenced by an array of risk factors, including genetic predisposition, environmental allergens, antenatal exposures, infections and psychosocial factors. One proposed mechanism by which these risk factors contribute to the development of atopic disease is through changes in the production of T helper cell type 1 (Th1) and T helper cell type 2 (Th2) cytokines. The objectives of this review are to discuss antenatal exposures that are associated with paediatric atopic diseases, to discuss the influence of the intrauterine environment on neonatal immune responses, to provide an overview of the Th1 and Th2 pathways and how they relate to atopic disease, and to summarise our current understanding of the association between cytokine responses in cord blood and the development of atopic disease in early childhood.

Stillbirth: a review.

Stillbirth occurs in nearly 1% of all births in the USA, and is one of the most common but least studied adverse pregnancy outcomes. The many risk factors for and causes of stillbirth are presented. Over the past several decades, the rate of stillbirth has been substantially reduced, with the reduction most apparent in those stillbirths previously occurring at term and/or in labor. Reductions have occurred because of reductions in risk factors (i.e. prevention of Rh disease and better control of diabetes), better antepartum monitoring of those with risk factors followed by early delivery for those fetuses found to be at risk (i.e. growth restriction, maternal pre-eclampsia), better intrapartum fetal monitoring, increases in Cesarean section for those at risk, and early detection of congenital anomalies followed by termination prior to the time that these early fetal deaths are classified as stillbirths. Finally, the value of using fetal autopsy and placental examination to determine the cause of death accurately, both for research purposes and for patient counseling in future pregnancies, is explored.

Stress and preterm birth: neuroendocrine, immune/inflammatory, and vascular mechanisms.

A growing literature suggests that maternal psychological and social stress is a significant and independent risk factor for a range of adverse reproductive outcomes including preterm birth. Several issues remain to be addressed about stress and vulnerability to stress during pregnancy. Of these, perhaps one of the most important questions relates to biologic plausibility. Parturition, the process that results in birth, is a biological phenomenon. Very little empirical research to date, however, has examined the role of biological processes, if any, as mediators of the relationship between stress and preterm birth. In this paper we discuss the maternal, placental, and fetal neuroendocrine, immune/inflammatory, and vascular processes that may bridge the experience of social adversity before and during pregnancy and the biological outcome of preterm birth.

Maternal stress is associated with bacterial vaginosis in human pregnancy.

OBJECTIVES: Maternal infection, particularly bacterial vaginosis (BV) in pregnancy, is one of the leading causes of adverse perinatal outcomes. The determinants of individual differences in susceptibility, or vulnerability, to maternal infections are poorly understood. This study examines whether chronic maternal stress predisposes women to infection during pregnancy, and if so, whether the effects of chronic stress on infection are independent of other established risk factors. METHODS: We conducted a cross-sectional, clinical prevalence study of chronic maternal stress and BV status in a sample of 454 pregnant women at 14.3+/-0.3 weeks gestation (+/-SEM). BV was diagnosed by Gram-stain of vaginal fluid samples; chronic maternal stress was assessed using the Cohen Perceived Stress Scale. Other established risk factors for BV, including maternal age, race/ethnicity, marital status, SES, and behaviors related to feminine hygiene, sexual practices, and substance use, were measured using a structured interview. RESULTS: Of the 454 women enrolled in this study, 224 (49%) were BV positive (Nugent score 7-10), 64 (14%) had intermediate vaginal flora (Nugent score 4-6), and 166 (37%) were BV negative (Nugent score 0-3). BV+ women had significantly higher chronic stress levels than BV- women (24.6+/-0.5 vs. 22.2+/-0.6 units (+/-SEM), respectively; t = 3.19; p < .01). Maternal sociodemographic variables (African-American race/ethnicity) and behavioral characteristics (vaginal douching, number of lifetime sexual partners, and use of illicit drugs) also were significantly associated with the presence of BV. After controlling for the effects of these variables, using a multivariable logistic regression model, chronic maternal stress remained a significant and independent predictor of BV status. Women in the moderate-stress group (third quartile) and high-stress (fourth quartile) group were 2.3 times (95% CI = 1.2-4.3) and 2.2 times (95% CI = 1.1-4.2) more likely to be BV+ than women in the low-stress group (bottom quartile). CONCLUSIONS: High levels of chronic stress during pregnancy are associated with bacterial vaginosis. The effect of chronic maternal stress is independent of the effects of other established sociodemographic and behavioral risk factors for BV.

Stress, infection and preterm birth: a biobehavioural perspective.

Preterm birth is currently the most important problem in maternal-child health in the United States. Epidemiological studies have suggested that two factors, maternal stress and maternal urogenital tract infection, are significantly and independently associated with an increased risk of spontaneous preterm birth. These factors are also more prevalent in the population of sociodemographically disadvantaged women who are at increased risk for preterm birth. Studies of the physiology of parturition suggest that neuroendocrine and immune processes play important roles in the physiology and pathophysiology of normal and preterm parturition. However, not all women with high levels of stress and/or infection deliver preterm, and little is understood about factors that modulate susceptibility to pathophysiological events of the endocrine and immune systems in pregnancy. We present here a comprehensive, biobehavioural model of maternal stress and spontaneous preterm delivery. According to this model, chronic maternal stress is a significant and independent risk factor for preterm birth. The effects of maternal stress on preterm birth may be mediated through biological and/or behavioural mechanisms. We propose that maternal stress may act via one or both of two physiological pathways: (a) a neuroendocrine pathway, wherein maternal stress may ultimately result in premature and/or greater degree of activation of the maternal-placental-fetal endocrine systems that promote parturition; and (b) an immune/inflammatory pathway, wherein maternal stress may modulate characteristics of systemic and local (placental-decidual) immunity to increase susceptibility to intrauterine and fetal infectious-inflammatory processes and thereby promote parturition through pro-inflammatory mechanisms. We suggest that placental corticotropin-releasing hormone may play a key role in orchestrating the effects of endocrine and inflammatory/immune processes on preterm birth. Moreover, because neuroendocrine and immune processes extensively cross-regulate one another, we further posit that exposure to both high levels of chronic stress and infectious pathogens in pregnancy may produce an interaction and multiplicative effect in terms of their combined risk for preterm birth. Finally, we hypothesise that the effects of maternal stress are modulated by the nature, duration and timing of occurrence of stress during gestation. A discussion of the components of this model, including a theoretical rationale and review of the available empirical evidence, is presented. A major strength of this biobehavioural perspective is the ability to explore new questions and to do so in a manner that is more comprehensive than has been previously attempted. We expect findings from this line of proposed research to improve our present state of knowledge about obstetric risk assessment for preterm birth by determining the characteristics of pregnant women who are especially susceptible to stress and/or infection, and to broaden our understanding of biological (endocrine, immune, and endocrine-immune interactions) mechanisms that may translate social adversity during pregnancy into pathophysiology, thereby suggesting intervention strategies.

Pennsylvania's early discharge legislation: effect on maternity and infant lengths of stay and hospital charges in Philadelphia.

OBJECTIVE: To assess the effect of maternal length of stay (LOS) legislation on LOS and hospital charges associated with Philadelphia resident live births from 1994 through 1997. DATA SOURCE/STUDY SETTING: This was a descriptive epidemiological study involving secondary data analyses of linked birth record and hospital discharge data pertaining to all Philadelphia resident live births occurring between January 1, 1994 and December 31, 1997. STUDY DESIGN: Using these linked data, trends in median and mean maternal and infant LOS and hospital charges were described for three distinct time periods: (1) a "prelegislative" period (January 1, 1994 through June 30, 1995); (2) a one-year period during which LOS legislation was introduced, debated, modified, and eventually passed by Pennsylvania lawmakers (July 1, 1995 through June 30, 1996); and (3) a "post-LOS law" period immediately following enactment of Act 85 mandating minimum LOS for mothers and their newborns (July 1, 1996 through December 31, 1997). LOS variables for both mothers and infants were calculated based on the actual number of hours elapsing between birth and discharge; hospital charges were obtained directly from information available in the Hospital Discharge Survey data. PRINCIPAL FINDINGS: Maternal median charges and LOS per delivery for vaginal births rose from 5,270 dollars to 6,333 dollars and from 35 to 47 hours following the enactment of Pennsylvania maternal minimum LOS legislation. Median infant cost and LOS per delivery mirrored these trends. CONCLUSIONS: Pennsylvania LOS legislation had a profound effect on maternal and infant discharge practices in Philadelphia. As much as $20 million may have been added to annual health care costs associated with Philadelphia resident births.

Bacterial vaginosis: a public health problem for women.

Bacterial vaginosis (BV) remains a moderately prevalent condition with clearly observed links to adverse reproductive, gynecological, and other outcomes in women, including human immunodeficiency virus infection. Because of inconsistent findings from clinical studies concerning BV's etiologic role, no definitive policies with respect to screening and treatment have yet been established. Of concern is the high, unexplained prevalence of BV among African-American women, who are also at extremely high risk for preterm birth. The complexity of the sociodemographic picture challenges the field of public health to continue to explore the role of BV and its relationship to a whole host of social and biomedical conditions that may contribute to adverse health outcomes among society's most vulnerable members. Future decisions about screening and treatment, currently based on the biomedical model, may need to take into consideration issues of social context and expanded views of causality if we are to better understand and eliminate those factors that place individual women at risk of adverse outcomes, as well as the conditions that underlie racial and ethnic disparities in health.

Teachers' receptiveness and comfort teaching sexuality education and using non-traditional teaching strategies.

This article reports on the comfort level of 97 eighth grade teachers using non-traditional teaching strategies in sexuality education classes. Most were comfortable teaching sexuality education and undeterred by external factors such as students' religious beliefs, lack of administrative support, or parental protest. However, a quarter to a third of teachers reported never or rarely using activities such as roleplays, small-group discussions, and problem-solving exercises. Multiple regression indicated that only gender was a significant predictor of such usage. The greatest perceived barriers to teaching sexuality education and using alternative teaching strategies were lack of materials, lack of time, and difficulty with facilitation under traditional classroom structure. Although more research is needed to better understand barriers to using alternative strategies, teachers in two focus groups (n = 19) suggested 1) restructuring classroom settings to match the demands of new teaching strategies, and 2) "experience appropriate" curricula.