Laura M. Glynn

Elevated maternal cortisol early in pregnancy predicts third trimester levels of placental corticotropin releasing hormone (CRH): Priming the placental clock

The purposes of this study were to determine the intervals when placental corticotrophic-releasing hormone (CRH) was most responsive to maternal cortisol. A sample of 203 women each were evaluated at 15, 19, 25 and 31 weeks gestation and followed to term. Placental CRH and maternal adrenocorticotropin hormone (ACTH), B-endorphin and cortisol were determined from plasma. CRH levels increased faster and were higher in women who delivered preterm compared with women who delivered at term (F3,603 = 5.73, p < .001). Simple effects indicated that CRH levels only at 31 weeks predicted preterm birth (F1,201 = 5.53, p = .02). Levels of cortisol were higher in women who delivered preterm at 15 weeks gestation (F1,201 = 4.45, p = .03) with a similar trend at 19 weeks gestation. Hierarchical regression suggested that the influence on birth outcome of maternal cortisol early in pregnancy was mediated by its influence on placental CRH at 31 weeks. Elevated cortisol at 15 weeks predicted the surge in placental CRH at 31 weeks (R = .49, d.f. = 1,199, Fchange = 61.78, p < .0001). Every unit of change in cortisol (microg/dl) at 15 weeks was associated with a 34 unit change of CRH (pg/ml) at 31 weeks. These findings suggested that early detection of stress signals by the placenta stimulated the subsequent release of CRH and resulted in increased risk for preterm delivery.

The role of rumination in recovery from reactivity: cardiovascular consequences of emotional states.

Objective While most investigations of the link between blood pressure responses and later disease have focused on acute reactivity during stressful tasks, there is some theoretical and empirical reason to believe that examining recovery and later re-creations of BP responses may also be useful. Two experiments explored situational determinants of sustained BP elevations, examining whether the extent of recovery and the ability to later mentally recreate the response are influenced by the magnitude or emotionality of the initial task and also whether preventing rumination after a stressor has ended speeds recovery. Method Experiment 1, with 72 normotensive male and female undergraduates, examined BP and heart rate before, during, and after a task and also before, during, and after the mental re-creation of that task. Four tasks were used, designed to produce high initial reactivity with an emotional component (mental arithmetic with harassment), low reactivity with emotion (shock avoidance), high reactivity without emotion (physical exercise), or low reactivity without emotion (cold pressor). Experiment 2, with 20 normotensive male and female undergraduates, compared the cardiovascular recovery of persons who were either given a distractor task or just sat quietly immediately after a mental arithmetic task. Results Study 1 revealed that only the emotional tasks were associated with delayed BP recovery and elevations during later rumination. Blood pressure during recovery and later rumination was independent of the original reactivity. Experiment 2 found that participants with the distractor, who presumably could not ruminate, showed better BP recovery. Conclusions Situations that put people at risk may include not just those that cause large BP elevations, but also emotion-producing situations that lead to sustained and recurring elevations.

Gender, social support, and cardiovascular responses to stress.

OBJECTIVE Laboratory research indicates that the presence of a supportive other can reduce physiological responses to a stressor. Whether there are gender differences, either on the part of the provider or the recipient, in this social support effect is explored. Such differences might shed some light on the frequent epidemiological reports of gender differences in social support and health. METHODS Male and female subjects gave an impromptu speech and received either standardized supportive or nonsupportive feedback from a male or female confederate. Blood pressure and heart rate were monitored continuously during baseline and speech periods. RESULTS Speakers with a supportive female audience showed a systolic increase of 25 mm Hg over baseline. Those with a nonsupportive female audience increased 36 mm Hg. A supportive male audience led to increases of 32 mm Hg, and a nonsupportive male audience 28 mm Hg. There was no significant effect of gender of subject. CONCLUSIONS Results indicate that social support provided by women reduced cardiovascular changes for both male and female speakers compared with presence of a nonsupportive female audience. Social support from men did not. These findings suggest a possible mechanism that might help explain the epidemiological literature on the relationship between gender, social support, and health. The findings are consistent with the notion that married men are healthier because they marry women. Women do not profit as much from marriage or suffer as much from separation, in terms of health outcomes, because the support they gain or lose is the less effective support of a man. These findings render more plausible the possibility that differences in social support might contribute to health differences, through the dampening of cardiovascular responses to stress.

Racial Differences in Birth Outcomes : The Role of General, Pregnancy, and Racism Stress

OBJECTIVE This study examined the role of psychosocial stress in racial differences in birth outcomes. DESIGN Maternal health, sociodemographic factors, and 3 forms of stress (general stress, pregnancy stress, and perceived racism) were assessed prospectively in a sample of 51 African American and 73 non-Hispanic White pregnant women. MAIN OUTCOME MEASURES The outcomes of interest were birth weight and gestational age at delivery. Only predictive models of birth weight were tested as the groups did not differ significantly in gestational age. RESULTS Perceived racism and indicators of general stress were correlated with birth weight and tested in regression analyses. In the sample as a whole, lifetime and childhood indicators of perceived racism predicted birth weight and attenuated racial differences, independent of medical and sociodemographic control variables. Models within each race group showed that perceived racism was a significant predictor of birth weight in African Americans, but not in non-Hispanic Whites. CONCLUSIONS These findings provide further evidence that racism may play an important role in birth outcome disparities, and they are among the first to indicate the significance of psychosocial factors that occur early in the life course for these specific health outcomes.

Familialism, social support, and stress: positive implications for pregnant Latinas.

This study examined the association of familialism, a cultural value that emphasizes close family relationships, with social support, stress, pregnancy anxiety, and infant birth weight. Foreign-born Latina (n = 31), U.S.-born Latina (n = 68), and European American (n = 166) women living in the United States participated in a prospective study of pregnancy in which they completed measures of familialism, social support, stress, and pregnancy anxiety during their second trimester. As expected, Latinas scored higher on familialism than European Americans. Familialism was positively correlated with social support and negatively correlated with stress and pregnancy anxiety in the overall sample. As predicted, however, the associations of familialism with social support and stress were significantly stronger among Latinas than European Americans. Moreover, higher social support was associated with higher infant birth weight among foreign-born Latinas only. Implications of cultural values for relationships and health are discussed.

Exposure to Prenatal Psychobiological Stress Exerts Programming Influences on the Mother and Her Fetus

Background/Aims: Accumulating evidence from a relatively small number of prospective studies indicates that exposure to prenatal stress profoundly influences the developing human fetus with consequences that persist into childhood and very likely forever. Methods: Maternal/fetal dyads are assessed at ∼20, ∼25, ∼31 and ∼36 weeks of gestation. Infant assessments begin 24 h after delivery with the collection of cortisol and behavioral responses to the painful stress of the heel-stick procedure and measures of neonatal neuromuscular maturity. Infant cognitive, neuromotor development, stress and emotional regulation are evaluated at 3, 6 12 and 24 months of age. Maternal psychosocial stress and demographic information is collected in parallel with infant assessments. Child neurodevelopment is assessed with cognitive tests, measures of adjustment and brain imaging between 5 and 8 years of age. Results:Psychobiological markers of stress during pregnancy, especially early in gestation, result in delayed fetal maturation, disrupted emotional regulation and impaired cognitive performance during infancy and decreased brain volume in areas associated with learning and memory in 6- to 8-year-old children. We review findings from our projects that maternal endocrine alterations that accompany pregnancy and influence fetal/infant/child development are associated with decreased affective responses to stress, altered memory function and increased risk for postpartum depression. Conclusions: Our findings indicate that the mother and her fetus both are influenced by exposure to psychosocial and biological stress. The findings that fetal and maternal programming occur in parallel may have important implications for long-term child development and mother/child interactions.

Pregnancy affects appraisal of negative life events.

OBJECTIVE It has been demonstrated that physiological responses to stress are diminished late in pregnancy. This study investigates whether emotional responding is diminished as well by measuring affective responses to specific life events during pregnancy. METHODS A total of 292 pregnant women reported the occurrence of and affective responses to a range of major life events during gestation. Two analyses were conducted (across events and within events) on these responses to determine whether life events occurring in the first trimester were rated as more stressful than those that occurred in the third trimester. RESULTS Both within-event and across-events analyses of responses to life events demonstrated that events occurring early in pregnancy were perceived as more stressful than events occurring later in pregnancy. CONCLUSION Responses to stress and affective state are progressively altered in pregnant women, suggesting that timing of stress exposure during gestation may be critical in determining its impact.

IS THERE A VIABILITY-VULNERABILITY TRADEOFF? SEX DIFFERENCES IN FETAL PROGRAMMING

OBJECTIVE In this paper we evaluate the evidence for sex differences in fetal programming within the context of the proposed viability-vulnerability tradeoff. METHODS We briefly review the literature on the factors contributing to primary and secondary sex ratios. Sex differences in fetal programming are assessed by summarizing previously published sex difference findings from our group (6 studies) and also new analyses of previously published findings in which sex differences were not reported (6 studies). RESULTS The review and reanalysis of studies from our group are consistent with the overwhelming evidence of increasing risk for viability among males exposed to environmental adversity early in life. New evidence reported here support the argument that females, despite their adaptive agility, also are influenced by exposure to early adversity. Two primary conclusions are (i) female fetal exposure to psychobiological stress selectively influences fear/anxiety, and (ii) the effects of female fetal exposure to stress persist into preadolescence. These persisting effects are reflected in increased levels of anxiety, impaired executive function and neurological markers associated with these behaviors. CONCLUSIONS A tacit assumption is that females, with their adaptive flexibility early in gestation, escape the consequences of early life exposure to adversity. We argue that the consequences of male exposure to early adversity threaten their viability, effectively culling the weak and the frail and creating a surviving cohort of the fittest. Females adjust to early adversity with a variety of strategies, but their escape from the risk of early mortality and morbidity has a price of increased vulnerability expressed later in development.

An historical context for behavioral models of hypertension

OBJECTIVE The purpose of this study is provide an historical context for current behavioral models of hypertension. METHODS A selective sample of the cardiovascular reactivity literature was reviewed, from 1932 to present. RESULTS In the earliest model, cardiovascular reactivity was regarded as a marker of disease risk; however, in later models, reactivity came to be viewed as a causal influence in the development of hypertension. As the models evolved, the underlying assumptions changed. Thus, the risk marker model assumed that cardiovascular responses to stress were a stable, generalized characteristic of the individual, and therefore the eliciting stimuli were arbitrary. The later models, however, assume that the nature of the eliciting stimulus is a determinant of the cardiovascular response. We describe the increasing complexity of the four models, and contrast their underlying assumptions and the implications of these assumptions. CONCLUSION We provide an overview of study designs and variables that should be incorporated into studies seeking to understand the ways in which cardiovascular responses to stress may influence the development of hypertension.

Poor Sleep Quality is Associated with Preterm Birth

STUDY OBJECTIVES Preterm birth (PTB) is a major public health priority and the most common adverse pregnancy outcome. Several risk factors have been identified, but a gap in the understanding of the underlying etiology of PTB persists. Poor sleep quality is a correlate of adverse health outcomes. Therefore, we evaluated whether sleep quality during pregnancy was a clinically relevant risk factor for PTB. DESIGN Observational. MEASUREMENTS AND RESULTS Participants included 166 pregnant women (mean age = 28.6 ± 5.5 years). Self-report questionnaires, including the Pittsburgh Sleep Quality Index (PSQI), were administered at 14-16, 24-26, and 30-32 weeks gestation. Logistic regression models were used to evaluate whether sleep quality was associated with preterm delivery. Poor sleep quality was a predictor of preterm birth, with the largest effects in early pregnancy (14-16 weeks) (OR: 1.25 95% CI [1.04-1.50], P = 0.02) and more modest effects in later pregnancy (30-32 weeks) (OR: 1.18 95% CI [0.98-1.42], P = 0.07). With every one-point increase on the PSQI, the odds of preterm birth increase 25% in early pregnancy and 18% in later pregnancy. CONCLUSIONS Poor sleep quality, in both early and late pregnancy, is associated with an increased risk of delivering preterm. Currently the specific pathway(s) through which disturbed sleep contributes to PTB are unknown. We suggest that poor sleep may contribute to increased risk for PTB both independently, as well as in conjunction with other established risk factors, such as stress.