Calvin J. Hobel

Children's Brain Development Benefits from Longer Gestation.

Disruptions to brain development associated with shortened gestation place individuals at risk for the development of behavioral and psychological dysfunction throughout the lifespan. The purpose of the present study was to determine if the benefit for brain development conferred by increased gestational length exists on a continuum across the gestational age spectrum among healthy children with a stable neonatal course. Neurodevelopment was evaluated with structural magnetic resonance imaging in 100 healthy right-handed 6- to 10-year-old children born between 28 and 41 gestational weeks with a stable neonatal course. Data indicate that a longer gestational period confers an advantage for neurodevelopment. Longer duration of gestation was associated with region-specific increases in gray matter density. Further, the benefit of longer gestation for brain development was present even when only children born full term were considered. These findings demonstrate that even modest decreases in the duration of gestation can exert profound and lasting effects on neurodevelopment for both term and preterm infants and may contribute to long-term risk for health and disease.

Plasma estrone, estradiol, estriol, progesterone, and 17-hydroxyprogesterone in human pregnancy: I. Normal pregnancy☆

To describe normal relationships between the various plasma unconjugated estrogens and progesterone during the second half of human pregnancy, the plasma concentrations of progesterone, 17-hydroxyprogesterone (17-OHP), and unconjugated estrone (E1), estradiol (E2), and estriol (E3) were measured in 126-310 normal women. Progesterone and unconjugated E1, E2, and E3 increased gradually throughout later pregnancy; 17-OHP increased only after the thirty-third week. At term the mean value of progesterone was 9 times higher than that 17-OHP. Throughout pregnancy the mean value of E2 was higher than that of E1 or E3. During the second half of pregnancy the ratios of progesterone to estradiol and estriol and of estradiol to estriol remained unchanged, indicating no preferential increase of plasma concentration of maternal or fetal hormones.

Prenatal and intrapartum high-risk screening

Abstract A high-risk pregnancy screening system based on a prospective analysis of prenatal, intrapartum, and neonatal factors in 738 pregnancies can predict perinatal morbidity and mortality. Factors were assigned with weighted values according to their assumed risk. Total scores for the prenatal, intrapartum, and neonatal period were dichotomized to simplify the scoring system by forming a low-risk group (scores

Psychosocial Stress and Pregnancy Outcome

This article is intended to help clinicians better understand the ever-expanding body of research on whether psychosocial stress (both acute and chronic) is linked to 2 major adverse pregnancy outcomes: preterm birth and low birth weight. We summarize the existing literature and then review assessment tools commonly used to diagnose various types of psychosocial stress, with attention to how and when assessments should be made. After discussing the physiologic mechanisms hypothesized to underlie these relationships, we examine the range of existing interventions aimed at reducing psychosocial stress and review their efficacy at improving birth outcomes. Future directions for prevention of adverse pregnancy outcomes are discussed and suggest that an entirely new approach may be necessary.

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.

Maternal prenatal anxiety and corticotropin-releasing hormone associated with timing of delivery

Objective: The high rate of preterm births is an imposing public health issue in the United States. Past research has suggested that prenatal stress, anxiety, and elevated levels of maternal plasma corticotropin-releasing hormone (CRH) are associated with preterm delivery in humans and animals. Studies to date have not examined all three variables together; that is the objective of this paper. Methods: Data from 282 pregnant women were analyzed to investigate the effect of maternal prenatal anxiety and CRH on the length of gestation. It was hypothesized that at both 18 to 20 weeks (Time 1) and 28 to 30 weeks gestation (Time 2), CRH and maternal prenatal anxiety would be negatively associated with gestational age at delivery. CRH was also expected to mediate the relationship between maternal prenatal anxiety and gestational age at delivery. Results: Findings supported the mediation hypothesis at Time 2, indicating that women with high CRH levels and high maternal prenatal anxiety at 28 to 30 weeks gestation delivered earlier than women with lower CRH levels and maternal prenatal anxiety. Women who delivered preterm had significantly higher rates of CRH at both 18 to 20 weeks gestation and 28 to 30 weeks gestation (p < .001) compared with women who delivered term. Conclusions: These findings are the first to link both psychosocial and neuroendocrine factors to birth outcomes in a prospective design. ANOVA = analysis of variance; BIPS = Behavior in Pregnancy Study; CRH = corticotropin-releasing hormone; HPA = hypothalamic-pituitary-adrenal axis; SNS = sympathetic nervous system.

Role of Psychosocial and Nutritional Stress on Poor Pregnancy Outcome

Epidemiological evidence suggests that maternal psychosocial stress, strenuous physical activity and fasting are independent risk factors for preterm birth and low birth weight. Data from clinical studies consistently demonstrate that women in preterm labor have significantly elevated levels of corticotropin-releasing hormone compared with age-matched control subjects. Because production of corticotropin-releasing hormone appears to be stress sensitive, this neuropeptide may play a critical role in the physiological mediation among stressful experiences, work stress and fasting and risk of preterm birth. In addition to the direct effect of elevated corticotropin-releasing hormone on the initiation of labor, it may have an immunomodulatory effect such that women with high levels of corticotropin-releasing hormone may be more susceptible to infection or the pathological consequences of infection. We review the epidemiological data linking maternal stress, physical stain and fasting to preterm birth and low birth weight and review the plausible biological pathways through which these exposures may increase risk of preterm birth. The timing of these exposures is considered important. Future research and clinical programs addressing these exposures must consider assessments and interventions before pregnancy.

Plasma human chorionic gonadotropin estrone estradiol estriol progesterone and 17-alpha-hydroxyprogesterone in human pregnancy. 3. Early normal pregnancy.

Abstract The concentrations of human chorionic gonadotropin (HCG), progesterone (P), 17α-hydroxyprogesterone (17-OHP), and unconjugated estrone (E 1 ), estradiol (E 2 ), and estriol (E 3 ) were measured by radioimmunoassay in plasma of 10 patients followed from the third to the thirteenth week of pregnancy. Up to the fifth week of pregnancy, an increase in the mean plasma concentration of E 1 , E 2 , P, and 17-OHP was observed. After the fifth week of pregnancy, however, only the mean plasma concentration of E 1 and E 2 continued to increase, whereas that of 17-OHP started to decrease and that of P remained unchanged until the tenth week of pregnancy. Unconjugated E 3 became detectable (> 50 pg. per milliliter) only after the ninth week of pregnancy, after which its level continued to increase gradually. The mean HCG plasma level increased until the tenth week of pregnancy, after which it began to decline. No correlation was found between HCG and E 2 or HCG and P plasma concentrations, but good correlation was found between E 1 and E 2 levels. The mean P plasma concentrations between the third and the fifth weeks of pregnancy was about 100 times higher than that of E 2 . By the thirteenth week of pregnancy, however, the mean P / E 2 ratio had decreased sixfold, reaching a ratio similar to that observed at the second half of pregnancy. Most levels of P, E 1 , and E 2 up to the seventh week of pregnancy were in the range found during the menstrual period. During the first 7 weeks of pregnancy, the diagnosis of intrauterine pregnancy cannot be made with certainty by determination of any of these steroid hormones.

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.