Acculturation, Acculturative Stress, Experience of Discrimination, and Cesarean Birth in Mexican American Women

Introduction: There is evidence that Mexican Americans are more likely to have cesarean birth than non-Hispanic White Americans. The purpose of this study was to identify factors related to acculturation along with psychological and sociodemographic factors associated with birth mode in a prospective cohort of Mexican American women in Texas. Methods: This secondary analysis included 244 Mexican American pregnant women. Women with a prior cesarean birth were excluded. Variable selection was guided by Berry's Theoretical Framework of Acculturation. Correlations and logistic regression were used to examine relationships and predict risk of cesarean birth. Mediators and moderators were also considered. Results: Eighty women birthed by cesarean. Analytic and parent samples were similar in all demographics. After controlling for parity in logistic regression, greater Spanish language-related acculturative stress (adjusted odds ratio [AOR], 1.06, 95% confidence interval [CI] [1.01, 1.11], p = .028) and experience of discrimination (AOR, 1.18, 95% CI [1.00, 1.38], p = .044) increased the odds of cesarean birth. The relationship between acculturative stress and birth mode was moderated by birth facility. Conclusion: Acculturative stress and discrimination may play a role in birth mode for Mexican American women birthing in Texas. Birth facility and acculturative stress may be interacting in ways that have clinical significance but are yet unexplored.

The mastery lifestyle intervention to reduce biopsychosocial risks for pregnant Latinas and African Americans and their infants: protocol for a randomized controlled trial

BACKGROUND

Pregnant Mexican Americans (hereafter called Latinas) and Black/African American women are at increased risk for psychological distress, contributing to preterm birth and low birthweight; acculturative stress combined with perceived stress elevates depressive symptoms in Latinas. Based on our prior research using a psychoneuroimmunology framework, we identified psychological and neuroendocrine risk factors as predictors of preterm birth in Latina women that are also identified as risk factors for Black/African American women.

METHODS/DESIGN

In this prospective, randomized controlled trial with parallel group design we will explore psychosocial, neuroendocrine, and birth outcome effects of the Mastery Lifestyle Intervention (MLI). The MLI is a culturally relevant, manualized, psychosocial, group intervention integrating two cognitive behavioral therapies for both pregnant Latinas and Black/African American women (total n = 221). Study inclusion criteria are: women with current pregnancy at 14-20 weeks gestation, ability to read and speak English or Spanish, self-identify as Latina of Mexican heritage or Black/African American, 18-45 years old, born in the US or Mexico, and currently living in the US. Participants must receive Medicaid or other government-supported insurance, and meet screening criteria for anxiety, depressive symptoms, or stress. Participants are randomly assigned to either the intervention (MLI) or usual care group (UCG) in groups of 6-8 participants that occur over 6 consecutive weeks. Data are collected at 3 time points: enrollment (14-20 weeks gestation), following treatment (20-26 weeks), and 6 weeks after treatment (32-36 weeks gestation). Additional outcome, mediating, and moderating data are collected from the electronic health record during pregnancy and at birth. Analyses will primarily use generalized linear mixed modeling (GLMM) to evaluate the relationships between predictors and outcomes.

DISCUSSION

This RCT will test the efficacy of two combined third generation cognitive behavioral therapies (the MLI), given in a group format over 6 sessions, as compared to a usual prenatal care group, for both Latina and African American pregnant women. If efficacious, it may be provided as an adjunct to routine prenatal care and improve mental health, as well as babies being born too small and too soon.

TRIAL REGISTRATION

The trial was retrospectively registered at ClinicalTrials.gov . Bethesda (MD): National Library of Medicine. Identifier NCT05012072 , Reducing Pregnancy Risks: The Mastery Lifestyle Intervention (MLI); August 19, 2021. The trial is currently recruiting participants.

Integrative Review of Disparities in Mode of Birth and Related Complications among Mexican American Women

INTRODUCTION

Cesarean rates are particularly high among Hispanic women in some regions of the United States, placing a disproportionate health burden on women and their newborns. This integrative review synthesized the literature on mode of birth (vaginal vs cesarean) and related childbirth complications (hemorrhage, surgical site infection, perineal trauma) among Mexican American women living in the United States.

METHODS

Four electronic databases, PubMed, Embase, CINAHL, and SCOPUS, were searched to identify studies meeting the inclusion criteria, research studies that included Mexican American women who were pregnant or postpartum. Results were limited to English language and publications that were peer-reviewed and published before May 2020. Covidence was used in article identification, screening, and assessment. Critical appraisal of the research was performed using the Quality Assessment Tool for Studies with Diverse Designs.

RESULTS

Ten articles met inclusion criteria. In some studies, Mexican American women born in the United States were more likely to have cesareans than women born in Mexico; in other studies, these findings were reversed. Mexican American women often had lower unadjusted cesarean rates compared with non-Hispanic white women, but adjusting for birth facility (some facilities perform more cesareans than others), sociodemographic, and risk factors often revealed Mexican American women have a higher adjusted risk for cesarean birth. Women with higher socioeconomic status had higher cesarean rates compared with women with lower socioeconomic status. In studies of birth outcome by level of acculturation, women who were US-oriented had higher rates of cesarean and more frequent perinatal complications. By ethnic subgroup, rates of cesarean and complications varied among Hispanic women.

DISCUSSION

Birth facility was associated with perinatal outcomes for Mexican American women; those who gave birth at higher-performing facilities had better outcomes when compared with women who gave birth at lower-performing facilities. After adjusting for pregnancy complications, Mexican American women had a greater risk for cesarean birth compared with non-Hispanic white women, a finding that may have clinical practice implications. Level of acculturation affected birth outcomes, but more research using precise instruments is needed.

Pregnant Mexican American Biopsychosocial/Cultural risks for adverse infant outcomes

Aims

To test a model of psychosocial/cultural/biological risk factors for poor birth outcomes in Latina pregnant women.

Design

An observational study measuring acculturation, progesterone, cortisol, cotinine, age, marital status, income, stress, depressive symptoms and coping. We tested a structural equation model to predict risk.

Methods

We obtained a convenience sample (N = 515) of low medical risk pregnant Mexican American Hispanic women at 22–24 weeks of gestation. Bilingual research nurses collected data from blood, urine and questionnaires. Self‐report measures were the Beck Depression Inventory‐II, the Perceived Stress Scale, the Acculturation Rating Scale for Mexican Americans‐II and the Brief Cope. We measured progesterone and cortisol in plasma and cotinine levels in urine by enzyme‐linked immunoassays.

Results

A PLS‐SEM model revealed that Mexican American Hispanic pregnant women who were younger, single, lower income, more acculturated and who had greater negative coping, stress and depression were most at risk for having earlier and smaller babies.

Pilot Study of the Mastery Lifestyle Intervention

BACKGROUND

Recognizing the effects of acculturation on quality of life and emotional health, especially during pregnancy, we developed an intervention that would target these factors in order to improve maternal well-being during the prenatal period and potentially improve infant outcomes, particularly preterm birth for Mexican-American women (Latinas).

OBJECTIVE

The purpose of these pilot studies was to test the acceptability, feasibility, and preliminary efficacy of the mastery lifestyle intervention (MLI) to decrease depressive and anxiety symptoms and improve coping as implemented in prenatal clinics with culturally homogenous groups of Latinas.

METHODS

The MLI was tested in three small pilot studies (n = 15), one in El Paso, Texas (an urban area), and two in Bastrop, Texas (a rural area outside Austin), for acceptability and feasibility. A pretest/posttest, quasi-experimental design was used with pregnant self-identified Mexican-American Latinas at 14-20 weeks' gestation. Measures of anxiety, depressive symptoms, and positive and negative coping were used.

RESULTS

Feasibility was a success in terms of implementation of the MLI in an active prenatal clinic setting and the use of electronic tablets for data collection and entry of data into REDcap. Satisfaction was high, with the location of the MLI being at their primary OB/GYN clinic. Participants reported that six intervention sessions appear to be ideal as was the class length of 1.5 to 2 hours. On Cohen's d, there were medium to large effect size decreases in depressive and anxiety symptoms and small to medium effect size decreases in the use of negative coping strategies and small effect sizes for increases in positive coping strategies.

DISCUSSION

Pilot testing of the MLI indicated that it was well accepted from the participants and feasible as a culturally tailored behavioral therapy administered in a group setting by nurse practitioners. Our initial pilot results also suggest preliminary efficacy as indicated by moderate to large Cohen's d effect sizes for depression and anxiety.

Oxidative Stress Levels Throughout Pregnancy, at Birth, and in the Neonate

BACKGROUND

Oxidative stress is associated with poor perinatal outcomes. Little is known regarding the longitudinal levels of oxidative stress in the perinatal period or the correlation between maternal and neonatal oxidative stress levels.

OBJECTIVE

Describe and compare oxidative stress, specifically superoxide, superoxide dismutase, catalase, and glutathione levels, over the perinatal period.

STUDY DESIGN

Longitudinal descriptive design using a convenience sample of medically high- and low-risk pregnant women (n = 140) from a maternal-fetal medicine and general obstetrics practice, respectively. Blood was obtained from women at 12-20 and 24-28 weeks' gestation and during labor, from the umbilical cord at birth, and from neonates at 24-72 hr after birth. Levels of superoxide were measured using electron paramagnetic resonance (EPR) spectroscopy; antioxidants (superoxide dismutase, catalase, and glutathione) were measured using commercial assay kits. Relationships between oxidative stress levels at different time points were examined using nonparametric methods. Pregnancy outcome was collected.

RESULTS

Demographic variables, outcome variables, and oxidative stress levels in maternal blood, cord blood, and infants differed between medically high- and low-risk women. Descriptive patterns for oxidative stress measures varied over time and between risk groups. Significant correlations between time points were noted, suggesting intraindividual consistency may exist throughout the perinatal period. However, these correlations were not consistent across each medical risk group.

CONCLUSION

EPR spectroscopy is a feasible method for the perinatal population. Results provide new information on perinatal circulating superoxide levels and warrant further investigation into potential relationships between prenatal and neonatal physiologic dysregulation of oxidative stress.

Micro RNA clusters in maternal plasma are associated with preterm birth and infant outcomes

The current study examined micro RNA (miRNAs) clusters from the maternal plasma to determine their association with preterm birth (PTB) and infant birth outcomes. A subsample of 42 participants who spontaneously delivered either preterm (≤37 weeks) or term was selected from a parent sample of 515 pregnant Mexican American women. Plasma samples and prenatal data were collected at a single mid-gestation time point (22–24 weeks’ gestation) and birth outcomes were obtained from medical records after delivery. Circulating miRNAs were analyzed by qPCR. When miRNAs were grouped according to chromosomal cluster rather than expression level, individual miRNAs correlated strongly with other individual miRNAs within their respective genomic locus. miRNAs from the c19mc cluster negatively correlated with c14mc miRNAs, and this relationship was more pronounced in PTB. Clusters c14mc was negatively associated with length of gestation; while the c19mc was positively associated with length of gestation and infant head circumference. Together, these findings suggest that groups of miRNAs from common chromosomal clusters, rather than individual miRNAs, operate as co-regulated groups of signaling molecules to coordinate length of gestation and infant outcomes. From this evidence, differences in cluster-wide expression of miRNAs are involved in spontaneous PTB.

Network Structure of Perinatal Depressive Symptoms in Latinas: Relationship to Stress and Reproductive Biomarkers

Based on emerging evidence, mood disorders can be plausibly conceptualized as networks of causally interacting symptoms, rather than as latent variables of which symptoms are passive indicators. In an innovative approach in nursing research, we used network analysis to estimate the network structure of 20 perinatal depressive (PND) symptoms. Then, two proof-of-principle analyses are presented: Incorporating stress and reproductive biomarkers into the network, and comparing the network structure of PND symptoms between non-depressed and depressed women. We analyzed data from a cross-sectional sample of 515 Latina women at the second trimester of pregnancy and estimated networks using regularized partial correlation network models. The main analysis yielded five strong symptom-to-symptom associations (e.g., cry-sadness), and five symptoms of potential clinical importance (i.e., high centrality) in the network. In exploring the relationship of PND symptoms to stress and reproductive biomarkers (proof-of-principle analysis 1), a few weak relationships were found. In a comparison of non-depressed and depressed women's networks (proof-of-principle analysis 2), depressed participants had a more connected network of symptoms overall, but the networks did not differ in types of relationships (the network structures). We hope this first report of PND symptoms as a network of interacting symptoms will encourage future network studies in the realm of PND research, including investigations of symptom-to-biomarker mechanisms and interactions related to PND. Future directions and challenges are discussed. © 2017 Wiley Periodicals, Inc.

Acculturation Predicts Negative Affect and Shortened Telomere Length

Chronic stress may accelerate cellular aging. Telomeres, protective "caps" at the end of chromosomes, modulate cellular aging and may be good biomarkers for the effects of chronic stress, including that associated with acculturation. The purpose of this analysis was to examine telomere length (TL) in acculturating Hispanic Mexican American women and to determine the associations among TL, acculturation, and psychological factors. As part of a larger cross-sectional study of 516 pregnant Hispanic Mexican American women, we analyzed DNA in blood samples ( N = 56) collected at 22-24 weeks gestation for TL as an exploratory measure using monochrome multiplex quantitative telomere polymerase chain reaction (PCR). We measured acculturation with the Acculturation Rating Scale for Mexican Americans, depression with the Beck Depression Inventory, discrimination with the Experiences of Discrimination Scale, and stress with the Perceived Stress Scale. TL was negatively moderately correlated with two variables of acculturation: Anglo orientation and greater acculturation-level scores. We combined these scores for a latent variable, acculturation, and we combined depression, stress, and discrimination scores in another latent variable, "negative affectivity." Acculturation and negative affectivity were bidirectionally correlated. Acculturation significantly negatively predicted TL. Using structural equation modeling, we found the model had an excellent fit with the root mean square error of approximation estimate = .0001, comparative fit index = 1.0, Tucker-Lewis index = 1.0, and standardized root mean square residual = .05. The negative effects of acculturation on the health of Hispanic women have been previously demonstrated. Findings from this analysis suggest a link between acculturation and TL, which may indicate accelerated cellular aging associated with overall poor health outcomes.

CRH as a Predictor of Preterm Birth in Minority Women

OBJECTIVE

To determine the predictive capability of corticotropin-releasing hormone (CRH) as a biomarker of preterm birth (PTB) in minority women.

STUDY DESIGN

Venous blood samples were obtained at 22-24 weeks' gestation in a prospective, descriptive study of 707 minority women experiencing low-risk pregnancies. CRH was analyzed using a radioimmunoassay and methanol extraction protocol.

RESULT

CRH predicted PTB in both African American and Hispanic women. The odds ratio was 1.8 times greater for having a PTB if the CRH level was >24 pg/ml. The median CRH for African American women having a PTB was 46.6 pg/ml and for Hispanic women was 35.03 pg/ml. Using a receiver-operating characteristic curve, the threshold for CRH among the African American women was 30.6 pg/ml and among the Hispanic women was 27.4 pg/ml.

CONCLUSION

CRH may be an important biomarker for predicting PTB in minority women, especially when combined with other predictors.

Psychological, cultural and neuroendocrine profiles of risk for preterm birth

Background

Preterm birth remains a major obstetrical problem and identification of risk factors for preterm birth continues to be a priority in providing adequate care. Therefore, the purpose of this study was to elucidate risk profiles for preterm birth using psychological, cultural and neuroendocrine measures.

Methods

From a cross sectional study of 515 Mexican American pregnant women at 22–24 weeks gestation, a latent profile analysis of risk for preterm birth using structural equation modeling (SEM) was conducted. We determined accurate gestational age at delivery from the prenatal record and early ultrasounds. We also obtained demographic and prenatal data off of the chart, particularly for infections, obstetrical history, and medications. We measured depression (Beck Depression Inventory), mastery (Mastery scale), coping (The Brief Cope), and acculturation (Multidimensional Acculturation Scale) with reliable and valid instruments. We obtained maternal whole blood and separated it into plasma for radioimmunoassay of Corticotrophin Releasing Hormone (CRH). Delivery data was obtained from hospital medical records.

Results

Using a latent profile analysis, three psychological risk profiles were identified. The “low risk” profile had a 7.7 % preterm birth rate. The “moderate risk” profile had a 12 % preterm birth rate. The “highest risk” profile had a 15.85 % preterm birth rate. The highest risk profile had double the percentage of total infections compared to the low risk profile. High CRH levels were present in the moderate and highest risk profiles.

Conclusion

These risk profiles may provide a basis for screening for Mexican American women to predict risk of preterm birth, particularly after they are further validated in a prospective cohort study. Future research might include use of such an identified risk profile with targeted interventions tailored to the Hispanic culture.

Perceptions of guided imagery for stress management in pregnant African American women

Maternal stress during pregnancy has been associated with numerous adverse pregnancy, birth, and health outcomes. Pregnant African American women have been reported to have higher levels of stress compared to other ethnic or racial groups underscoring the need for effective interventions to reduce stress in this population. The purpose of this study was to gain an in-depth understanding of the perceptions of guided imagery (GI) as a technique for stress management in a cohort of pregnant African American women who participated in a GI intervention as part of a larger mixed methods randomized controlled trial. The 12week intervention was a professionally recorded compact disc with four tracks developed and sequenced to reduce stress and associated symptoms. The findings from this descriptive phenomenologic study were derived from daily logs and interviews from 36 participants randomized to the GI group. Participants described the stressful nature of their lives. Results demonstrated pregnant African American women perceived the intervention as beneficial in reducing stress and the associated symptoms. The emergent themes suggested the intervention offered a respite from their stressful lives, reduced the negative emotional responses to stress and enhanced well-being, benefited other areas of their daily life, and provided an opportunity to connect with their baby. The study results support the perceived efficacy of GI as a stress coping intervention. GI is an economic as well as easy to implement, access and use technique that has potential stress coping benefits as perceived by pregnant African American women.

An ELISA method to compute endpoint titers to Epstein-Barr virus and cytomegalovirus: application to population-based studies

Indirect fluorescence analysis (IFA), the gold standard for determining herpesvirus antibody titers, is labor-intensive and poorly suited for large population-based studies. The enzyme-linked immunosorbent assay (ELISA) is used widely for measuring antiviral antibodies but also suffers drawbacks such as reduced specificity and the qualitative nature of the results due to limited interpretation of the optical density (OD) units. This paper describes a method to titer herpesvirus antibodies using microplates coated with virally-infected cells in which a standard curve, derived from IFA-scored samples, allowed OD units to be converted into titers. A LOOKUP function was created in order to report the data as traditional IFA-based (i.e., 2-fold) titers. The modified ELISA correlated significantly with IFA and was subsequently used to compute endpoint antibody titers to Epstein-Barr virus (EBV)-virus capsid antigen (VCA) and cytomegalovirus (CMV) in blood samples taken from 398 pregnant Hispanic women. Four women were EBV negative (1%), while 58 women were CMV negative (14.6%). EBV VCA antibody titers were significantly higher than CMV antibody titers (p<0.001). This method allows titering of herpesvirus antibodies by ELISA suitable for large population-based studies. In addition, the LOOKUP table enables conversion from OD-derived titers into 2-fold titers for comparison of results with other studies.

Family cohesion, acculturation, maternal cortisol, and preterm birth in Mexican-American women

Objective

To examine the potential moderating effects of family cohesion and acculturation on the physiological stress response (cortisol) as a predictor of preterm birth (PTB) in pregnant Mexican-American women.

Methods

The sample included 470 participants; 33 had preterm births. All participants were self-identified as Mexican-American. In this cross-sectional study, family cohesion was measured by a self-report questionnaire. Acculturation was measured by self-report questionnaire as well as by years in the United States and country of birth. Stress was measured by serum cortisol. All measures were obtained at 22–24 weeks gestation. Additional data including history of PTB were obtained from the health record. Data analysis was primarily conducted using logistic regression.

Results

The relationship between stress and PTB was predicted by family cohesion (estimate/ standard error [E/SE] = −2.46, P = 0.014) and acculturation (E/SE = 2.56, P = 0.011). In addition, there was an interaction between family cohesion and history of previous PTB (E/SE = −2.12, P = 0.035).

Conclusion

Results indicate that the impact of cortisol on PTB is predicted by acculturation and family cohesion such that higher levels of cortisol in conjunction with higher levels of acculturation and lower levels of family cohesion are associated with increased risk of PTB. In addition, low family cohesion in combination with a history of PTB was associated with higher levels of PTB. Assessment of family cohesion, including problem solving, adherence to family decisions, family shared space, and activity, should be included as part of prenatal assessment for risk of PTB. Subsequently, interventions that focus on improving the individual’s response to an imbalance in family functioning are needed. In addition, prenatal assessment of level of acculturation may also identify those who are at risk for PTB.

Invited commentary: maternal stress and stillbirth: another piece of the puzzle

Although numerous causes and risk factors for stillbirth have been described, there are many cases that remain unexplained. In addition, the relationship between various risk factors and potential etiologies remains uncertain. This has contributed to a plateau in stillbirth rates in developed countries. In this issue of the Journal, László et al. (Am J Epidemiol. 2013;177(3):219-227) present some of the first data clearly linking maternal stress and stillbirth. This is biologically plausible, since many of the bioactive mediators of stress contribute to the pathophysiology of stillbirth. Stress is an attractive potential risk factor for stillbirth, since in some cases it may be modified. However, it is important to be careful when counseling families about the relationship between stress and stillbirth so that they do not blame themselves for the event. These data should spur additional investigation into the link between stress and stillbirth, hopefully leading to fewer fetal deaths.

Psychological distress and SSRI use predict variation in inflammatory cytokines during pregnancy

Evidence supports the premise that maternal psychological distress adversely affects pregnancy outcomes and that inflammatory markers and placentally-produced corticotrophin-releasing hormone (pCRH) are likely mediating factors. The primary aim of the study was to explore the associations between maternal psychological distress, use of selective serotonin re-uptake inhibitors, pCRH, and maternal plasma inflammatory markers during pregnancy. Measures of maternal plasma pCRH, Interleukins-1, 6, & 10, C-Reactive Protein, Macrophage Migration Inhibitory Factor, and Tumor Necrosis Factor-α were completed in 100 pregnant women. Measures of depression, anxiety, and perceived stress were completed, as well as collection of demographic/behavioral data, e.g. use of selective serotonin re-uptake inhibitors (SSRIs). Significant correlations were found at 14-20 weeks gestation between IL-6 & 10, and depression, anxiety, and perceived stress. Also at 14 - 20 weeks gestation, IL10 levels were significantly lower in women with 4th quartile pCRH levels and IL1β, IL6, and IL10 were significantly lower among women who took an SSRI during pregnancy. After controlling for maternal age, BMI, pCRH level, and SSRI use, psychological distress remained to explain variation in maternal inflammatory markers. These results might suggest that future research should focus on whether depression and anxiety are effectively being treated during pregnancy, and how such a scenario might contribute to an immune system pathway to poor pregnancy outcome.

Interleukin-10 predicts preterm birth in acculturated Hispanics

OBJECTIVE

Among Hispanics living in the United States, acculturation is associated with an increased risk for preterm birth. Inflammatory pathways are also associated with preterm birth. As such, the current study sought to investigate the potential relationships among preterm birth, acculturation of Hispanic women, and inflammatory markers.

STUDY DESIGN

The authors performed an observational study on pregnant Hispanic women in Texas at 22-24 weeks' gestation (n = 470). The authors obtained demographic data prenatally as well as birth outcome data from the medical chart after delivery. The authors obtained venous blood and used plasma to assay interleukin-1 receptor antagonist (IL-1RA), interleukin-6 (IL-6), and interleukin-10 (IL-10). The authors used logistic regression to understand whether the presence or the absence of IL-10 levels was related to acculturation and the risk of preterm birth.

RESULTS

The authors observed interactions between undetectable IL-10 levels and years in the United States and undetectable IL-10 levels and being born in the United States in models predicting preterm birth. Follow-up probes of these interactions suggested that when IL-10 was undetectable, preterm birth became more likely as time living in the United States increased, χ(2) = 5.15 (1, 416), p = .020, odds ratio (OR) = 3.17, and was more likely in participants born in the United States than in those born elsewhere, χ(2) = 5.35 (1, 462), p = .020, OR = 16.78. The authors observed no interactions among acculturation, preterm birth, and IL-1RA and IL-6 levels.

CONCLUSION

Acculturated Hispanics who lack the protective effects of IL-10 experience a markedly higher risk of preterm birth than nonacculturated Hispanics.

Acculturation, depressive symptoms, estriol, progesterone, and preterm birth in Hispanic women

We examined the effects of acculturation, depressive symptoms, progesterone, and estriol (E3) as predictors of preterm birth (PTB) in pregnant Hispanic women. This cross-sectional study recruited a sample of 470 Hispanic women between 22- and 24-week gestation from physician practices and community clinics. We used the CES-D to measure maternal depressive symptoms. We measured acculturation by English proficiency on the Bidimensional Acculturation Scale, residence index by years in the USA minus age, nativity, and generational status. Serum progesterone and E3 were analyzed by EIA. Ultrasound and medical records determined gestational age after delivery. In χ (2) analysis, there were a significantly greater percentage of women with higher depressive scores if they were born in the USA. In a structural equation model (SEM), acculturation (English proficiency, residence index, and generational status) predicted the estriol/progesterone ratio (E/P), and the interaction of depressive symptoms with the E/P ratio predicted PTB. Undiagnosed depressive symptoms during pregnancy may have biological consequences increasing the risk for PTB.

Discrimination, acculturation and other predictors of depression among pregnant Hispanic women

OBJECTIVE

The purpose of our study was to examine the effects of socioeconomic status, acculturative stress, discrimination, and marginalization as predictors of depression in pregnant Hispanic women.

DESIGN

A prospective observational design was used.

SETTING

Central and Gulf coast areas of Texas in obstetrical offices.

PARTICIPANTS

A convenience sample of 515 pregnant, low income, low medical risk, and self-identified Hispanic women who were between 22-24 weeks gestation was used to collect data.

MEASURES

The predictor variables were socioeconomic status, discrimination, acculturative stress, and marginalization. The outcome variable was depression.

RESULTS

Education, frequency of discrimination, age, and Anglo marginality were significant predictors of depressive symptoms in a linear regression model, F (6, 458) = 8.36, P<.0001. Greater frequency of discrimination was the strongest positive predictor of increased depressive symptoms.

CONCLUSIONS

It is important that health care providers further understand the impact that age and experiences of discrimination throughout the life course have on depressive symptoms during pregnancy.

Effects of acculturation on the reporting of depressive symptoms among Hispanic pregnant women

BACKGROUND

Significant differences have been reported in the prevalence of depression between Mexicans and Mexican Americans. Whether the differences in prevalence are real or are the results of cultural bias in instrumentation is not known.

OBJECTIVES

To examine the association between acculturation and the responses to the individual depressive symptom item of the Center for Epidemiologic Studies Depression Scale (CES-D).

METHODS

The CES-D was administered to 395 Hispanic women during their 22-24 weeks' pregnancy clinic visit. Acculturation was defined by a subject's language preference of English or Spanish when completing the CES-D. Those who preferred English belong to the acculturated group and those who preferred Spanish are considered nonacculturated. Logistic regression was used to conduct differential item functioning (DIF) analysis for each of the 20 CES-D items to determine whether they operated differently between the acculturated Hispanic group and the nonacculturated Hispanic group.

RESULTS

Reliability of the CES-D total score was .86 and .88 for the nonacculturated and acculturated groups, respectively. None of the items of the Depressed Affect Subscale showed DIF. However, DIF was found in four out of the seven items in the Somatic Activity Subscale and in three out of the four items in the Positive Affect Subscale.

DISCUSSION

The results suggest that even within a homogenous Hispanic group of mostly Mexican Americans, responses to the CES-D differ by acculturation. The nonacculturated group are less likely to endorse somatic symptoms but more likely to endorse positive items than the acculturated group. Depression screening in this population needs to account for acculturation differences within the Hispanic group.

The relationships among acculturation, body mass index, depression, and interleukin 1-receptor antagonist in Hispanic pregnant women

OBJECTIVE

The purpose of this study was to determine relationships between acculturation, body mass index (BMI), and depressive symptoms with the Interleukin 1-mediated inflammatory response marker IL-1RA in pregnant Hispanic women at 22-24 weeks gestation.

DESIGN

An observational, prospective design with data collected at 22-24 weeks gestation.

SETTING

Public prenatal health clinics and private physician practices in central and south Texas serving low-income women.

MAIN OUTCOME MEASURES

Body mass index (BMI), depression scores on the Center for Epidemiological Studies of Depression (CES-D), years in the United States, the Language Proficiency Scale (LPS), and Interleukin 1 receptor antagonist levels (IL-1RA).

RESULTS

The longer the Hispanic women were in the United States, the higher the IL-1RA levels in plasma (F=4.55; P=.002). IL-1RA plasma levels were significantly different between low and normal BMI vs overweight and obese categories of BMI (F=8.54; P<.001). IL-1RA levels were significantly higher between those women who had high scores for depressive symptoms on the CES-D (using a cut off of 20) and those who had scores less than 20 (t-value=-2.41; P=.018). In structural equation modeling, years in the United States significantly positively predicted increased depressive symptoms, increased BMI, and increased IL-1RA levels with a good model fit.

CONCLUSIONS

We found that increasing years of residency in the United States is associated with the elevated inflammatory marker IL-1RA, and increased BMI. Increased depressive symptoms also predict IL-1RA levels among Hispanic women at 22-24 weeks of pregnancy. The significance of these findings is discussed in relationship to the development and course of disease.

The relationships among acculturation, biobehavioral risk, stress, corticotropin-releasing hormone, and poor birth outcomes in Hispanic women

OBJECTIVE

To determine the predictive ability of acculturation as an antecedent of stress, biobehavioral risk, corticotropin-releasing hormone levels, and poor birth outcomes in pregnant Hispanic women.

DESIGN

A prospective, observational design with data collected at 22-25 weeks of gestation and at birth through medical record review.

SETTING

Public prenatal health clinics in south Texas serving low-income women.

PARTICIPANTS

Self-identified Hispanic women who had singleton pregnancies, no major medical risk complications, and consented to answer questionnaires as well as a venipuncture and review of their prenatal and birth medical records.

MAIN OUTCOME MEASURES

Gestational age, Apgar scores, length, weight, percentile size, and head circumference of the infant at birth.

RESULTS

Significant differences were seen in infant birth weight, head circumference, and percentile size by acculturation. English acculturation predicted stress, corticotropin-releasing hormone, biobehavioral risk, and decreased gestational age at birth.

CONCLUSIONS

Investigation must continue to understand the circumstances that give rise to the decline in birth outcomes observed in Hispanics with acculturation to the dominant English culture in the United States.

Effects of maternal prenatal stress on infant outcomes: a synthesis of the literature

There is growing evidence that maternal prenatal stress may be hazardous to infant health. Changes in maternal hormonal and immune function as a result of stress may adversely affect the immune function and neurodevelopment of the fetus. Prenatal stress in the mother may produce lasting effects on the (1) infant's health status, (2) development and function of the infant's immune system, and (3) neurocognitive development of the infant. This article provides a synthesis of current human and animal literature on the effects of maternal prenatal stress on the developing fetus and the infant, with the resulting model evolving out of the framework of psychoneuroimmunology. The intent of the authors is an integrative review. The authors examined the following research question: What effect does maternal prenatal stress have on infants' immune development and neurodevelopment? All relevant studies were reviewed with no exclusion criteria. Major databases (CINAHL, MEDLINE, PsychINFO) were searched using a combination of the following key words: prenatal stress, cytokines, thymus, and infant neurodevelopment.

The Utility of fFN for the Prediction of Preterm Birth in Twin Gestations

OBJECTIVE

To determine the sensitivity, specificity, and positive predictive value (PPV) of fetal fibronectin (fFN) and to determine its usefulness, in conjunction with selected other clinical assessment measures, in the prediction of preterm birth for women with twin gestations.

DESIGN

A prospective, descriptive, longitudinal design.

SETTING

An obstetrical high-risk clinic that received patient referrals from several surrounding communities in central Texas.

PATIENTS/PARTICIPANTS

Forty-eight women identified with twin gestations prior to the 22nd week of pregnancy; primarily of Hispanic ethnicity.

MAIN OUTCOME MEASURES

A substantial number of outcome variables were assessed in this study. In the present report, data derived from weekly assessments for the identification of the presence of fFN, the diagnosis of bacterial vaginosis, and the measurement of cervical length were reviewed for their relationship to prematurity, birth weight, birth weight discordancy and placental chorionicity.

RESULTS

The relative risk of birth prior to 35 weeks gestation, fetal death, or discordance of twin birth weights of greater than 20% was 2.22 (CI: 1.09, 4.55, P < 0.015) when fFN was found to be positive at any weekly testing after 22 to 24 weeks gestation (sensitivity 76.82%, specificity 58.33%, PPV 66.7%). The presence of fFN was most highly predictive of preterm birth when performed during the 24th to 28th gestational week. Shorter cervical lengths were highly correlated with preterm birth (r = -0.6). An association between bacterial vaginosis and preterm birth was not demonstrated in this sample.

CONCLUSION

Sampling for the presence of fetal fibronectin can be easily accomplished by RNs in labor triage units and by advanced practice nurses in outpatient settings. The identification of fFN, particularly during the 24 to 28 weeks gestational time frame, is highly predictive of preterm birth, and particularly so for women with twin gestations.

Predicting risk of preterm birth: the roles of stress, clinical risk factors, and corticotropin-releasing hormone

The relationships and predictive abilities of perceived stress, selected clinical risk factors, and corticotropin-releasing hormone (CRH) levels in maternal plasma were investigated for their association with preterm labor (PTL), preterm birth, and gestational age at delivery. An exploratory, prospective, longitudinal research design was used to measure CRH 4 times over pregnancy, perceived stress at 24 and 32 weeks of pregnancy, clinical risk factors, and genitourinary infections in low-income women. Multiple regression analyses revealed that a model of measurement ofperceived stress at 24 or 32 weeks, CRH at 24 or 32 weeks, and PTL (indicated by a diagnosis by the physicians on the medical record and greater than 5 contractions per hour on the fetal monitor) was predictive of as much as 0.23 to 0.27 of the variance in gestational age at birth. Entering ethnicity as a variable into a model did not improve the predictive value. An analysis of variance between Caucasian and Hispanic ethnic groups revealed differences in CRH levels. However, simple regression analysis of ethnicity as a predictor showed a weak r2 with no significance for prediction. There was some evidence of an association of smoking with stress and both PTL and preterm birth. The measurement of stress combined with the measurement of CRHfrom maternal plasma may improve the prediction of which pregnant women are at riskfor pretern birth. The measurement of CRH has potential as an early biological marker of preterm birth.

Relationships of cortisol, perceived stress, genitourinary infections, and fetal fibronectin to gestational age at birth

The authors investigated the role of stress and cortisol with patients having preterm labor (PTL) and preterm birth (PTB). The relationships of maternal cortisol, perceived stress, fetal fibronectin (fFN), and genitourinary infections to PTL and PTB were studied. A prospective, longitudinal, observational study (n = 78) was conducted in a private practice in central Texas. Subjects had 4 blood draws for cortisol measurements grouped by 15-19, 20-22, 23-26, 27-30, and 31-35 weeks of gestation. Subjects had 2 vaginal swabs forfFN, chlamydia, and bacterial vaginosis screens at 23-26 and 27-30 weeks with assessment of psychosocial stress at 23-26 and 31-35 weeks. Statistical analysis was by analysis of variance, Pearson correlations, Fisher exact test, and logistic regression. There were no significant differences between the PTB, PTL, and term groups on cortisol levels at any of the gestational periods. Cortisol concentrations at any gestational stage did not correlate with gestational age at birth. A relationship of cortisol to race was observed when comparing Caucasians to other ethnic groups. A correlation (r = 0.42, P < 0.001) between the change in Perceived Stress Scale (PSS) score and gestational age was observed. The greater the decrease in PSS scores, the longer was the gestational age. A significant increase in cortisol at 19-21 weeks (P < 0.04), 23-26 weeks (P < 0.05), and 31-35 weeks (P < 0.01) was observed in patients having genitourinary infection. PTL was also significantly increased in subjects having positive genitourinary infections at either 23-26 weeks or 27-30 weeks (P < 0.01). The sensitivity of fFN to predict PTL collected at 27-30 weeks was 40%, specificity 86%, positive predictive value 55%, and negative predictive value 83%. These results indicate that cortisol is a poor predictor of either PTL or PTB. A decrease in perceived stress during the 2nd trimester was associated with an increase in length of gestation, suggesting the possibility of stress reduction as an appropriate intervention for lengthening gestational age.

Determination of allicin, S-allylcysteine and volatile metabolites of garlic in breath, plasma or simulated gastric fluids

Various components of garlic and aged garlic extract, including allicin, S-allylcysteine (SAC) and volatile metabolites of allicin were determined in breath, plasma and simulated gastric fluids by HPLC, gas chromatography (GC) or HPLC- and GC-mass spectrometry (MS). Data indicate that allicin decomposes in stomach acid to release allyl sulfides, disulfides and other volatiles that are postulated to be metabolized by glutathione and/or S-adenosylmethionine to form allyl methyl sulfide. SAC can be absorbed by the body and can be determined in plasma by HPLC or HPLC-MS using atmospheric pressure chemical ionization (APCI)-MS.

Specialized care for twin gestations: improving newborn outcomes and reducing costs

OBJECTIVE

To compare newborn outcomes and costs of hospital stays for twins born to mothers receiving care in a specialized twin clinic with a research-based care protocol and one consistent caregiver versus twins whose mothers received standard prenatal care.

DESIGN AND SETTING

A retrospective, historical cohort study conducted in a high-risk obstetric clinic in central Texas.

PATIENTS

Thirty women pregnant with twins received specialized care. The comparison group consisted of 41 women pregnant with twins who received standard care.

INTERVENTIONS

An advanced practice nurse provided prenatal care, which included weekly clinic visits, home visits, and 24-hour availability for phone support.

OUTCOME MEASURES

Gestational age at birth, birth weight, length of stay in the neonatal intensive-care unit (NICU), and hospital charges for the newborns.

RESULTS

No newborns of less than 30 weeks gestation were born to women in the specialized care group, the mean birth weight was 249 g (SD +/- 77) higher, days in the NICU were reduced from a mean of 17 to 7, and hospital charges were $30,000 less per infant.

CONCLUSIONS

Newborn outcomes were improved and length of stay and hospital charges were significantly reduced for newborns whose mothers had received care in the specialized twin clinic.

The determination of metabolites of garlic preparations in breath and human plasma

Gas Chromatography-Mass Spectrometry (GC-MS) was the major technique used to determine various metabolites after consumption of dehydrated granular garlic and an enteric-coated garlic preparation, in breath, plasma, and simulated gastric fluids. A special short-path thermal desorption device was used as an introduction technique for the gas chromatograph for the determination of volatiles. These garlic preparations release allicin, which decomposes in stomach acid or with time in the intestine to release allyl sulfides, disulfides and other volatiles, some of which are postulated to be metabolized by glutathione and/or S-adenosylmethionine to form allyl methyl sulfide, the main sulfur containing volatile metabolite. S-Allylcysteine, a non-volatile bioactive component of aged garlic preparations, was determined in human plasma and urine by HPLC-MS using the negative ion atmospheric pressure chemical ionization mode (APcI)- MS. The technique of selected ion monitoring was used for quantitation. A synthetic internal standard of deuterated S-allylcysteine was added to the plasma or urine to ensure recovery and to obtain reliable quantitative data.

Psychoneuroimmunology and preterm birth. A holistic model for obstetrical nursing practice and research

This article presents a framework through which nurses can conceptualize premature labor and birth for both practice and research. Use of the psychoneuroimmunology (PNI) model may guide the study of the problem of preterm birth in a more holistic manner, discovering relationships between the body and the mind that may affect how nurses can intervene to prevent premature birth. Nursing assessment of risk needs to include those situations that may lead to increased stress or anxiety, as is supported by research based on the PNI model. Reduction of stressors that lead to physiological changes related to the stress response can affect the incidence of preterm labor. Interventions to decrease stress and poor coping behaviors need to be tested and integrated into practice.

The measurement of stress in pregnancy

Stress is thought to be one of the biopsychosocial factors that contribute to adverse pregnancy outcomes, such as preterm labor and low birthweight. Identification of these factors (as in total number), and measurement of their individually perceived importance (severity) could lead to opportunities for intervention, and improved pregnancy outcome. A pilot study of the Daily Hassles Scale, was conducted in order to determine the appropriateness of its use among pregnant women. Daily hassles were thought to be a valid proxy for prenatal stress. Content and construct validity were determined among a sample of four content experts and 30 pregnant women. The Daily Hassles Scale proved to be a reliable (internally consistent) measure of stress (alpha reliability coefficient of 0.90). Further adaptation of the scale to include hassles specific to pregnancy and further testing of its usefulness among diverse multicultural and ethnic populations is warranted.

Mechanisms of full-term and preterm labor: factors influencing uterine activity

OBJECTIVE

To review factors influencing uterine activity leading to delivery.

DATA SOURCES

A search was conducted on MEDLINE and CINAHL under the terms "preterm labor," "preterm delivery," and "physiology of labor and preterm labor."

STUDY SELECTION

One-hundred fifty articles were reviewed, with selection based on physiologic concepts judged to be most relevant to nursing practice.

DATA SYNTHESIS

In this review, factors initiating labor and preterm labor (PTL) are identified, along with areas for further research.

CONCLUSIONS

Despite research on what initiates labor, it is unknown how the various mechanisms are integrated. Nurses are in a position to conduct research to help further the understanding of the labor and PTL processes. Nurses can use their assessment skills to help identify women at risk for PTL and delivery.

The research basis for prevention of preterm delivery in twin gestations

The purpose of this review is to explore interventions to improve the preterm delivery (PTD) rate in twin gestations. The increased mortality rate of twin gestations is strongly associated with low birth weight and PTD. Current evidence-based interventions such as specialized, comprehensive care by a consistent provider (such as an advanced practice nurse) should be implemented. Research is still needed for improved early detection and interventions to decrease risk factors for PTD. Nursing research is challenged to further develop interventions to improve perinatal outcomes in twin gestations and to decrease the burdens of premature delivery for our nation.