Prenatal stress and risk of spontaneous abortion

The impact of prepartum pandemic-related perceived stress on anxiety symptoms in the postpartum: The role of perceived childbirth experiences

Postpartum anxiety is a significant component of postpartum maternal distress and is related to adverse outcomes for both the mother and the child. Although previous research reported higher anxiety symptoms in pregnant women during the Covid-19 pandemic, no studies evaluated the negative impact of pandemic-related perceived stress on postpartum anxiety symptomatology over time. This study aimed to examine the impact of prepartum pandemic-related stress on postpartum anxiety and to evaluate the role of subjective labor and delivery experiences on this relationship. A sample of 172 pregnant women completed an online questionnaire evaluating pandemic-related perceived stress and anxiety symptoms in the second or third trimester of pregnancy. In the postpartum, they completed a second questionnaire retrospectively evaluating their childbirth experience and assessing anxiety symptoms in the last two weeks. A mediation analysis was conducted. Prepartum pandemic-related perceived stress was significantly associated with postpartum anxiety symptoms. Moreover, childbirth experiences significantly and partially mediated this relationship. Findings highlighted the importance of evaluating perceived stress levels during pregnancy to prevent negative consequences on postpartum mental health. Clinicians need to foster better management of factors included in the childbirth experience that may potentially trigger or counteract anxiety risk.

Does being infected with SARS-CoV-2 in the first-trimester increase the risk of miscarriage?

Aim of this study is to investigate whether the risk of miscarriage increases in pregnant women who had COVID-19 in first trimester. Our study included 52 patients with SARS-CoV-2 infection detected by RT-PCR and 53 patients with negative RT-PCR test in samples taken with nasopharyngeal swab in the first trimester between March 1 and December 31, 2020. Complete abortion, incomplete abortion, blighted ovum, intrauterine exitus, biochemical pregnancies were accepted as in the miscarriage group (MG). Pregnant women with COVID-19 and control group were compared in terms of demographic data, miscarriage rate and laboratory results. Patients were divided into MG and ongoing pregnancy groups (OPG) and compared in terms of the diagnosed weeks, clinical findings, laboratory results, treatments, and hospitalization. While miscarriage was observed in 15 (28.8%) of pregnant women infected with SARS-CoV-2 in the first trimester, this number was 7 (13.2%) in the control group. While the common symptoms in the MG were cough (60%), fever (53.3%), shortness of breath (53.3%), and fatigue (46.7%) (p<0.05); asymptomatic patients (51.4%) were higher in the OPG (p<0.001). Hospitalized patients were 33.3% in the MG and 8.1% in the OPG (p=0.02). According to the results of our study, the risk of miscarriage increases in pregnant women infected with SARS-CoV-2 (especially in severe infection) in the first trimester.

Conflict violence reduction and pregnancy outcomes: A regression discontinuity design in Colombia

BACKGROUND

The relationship between exposure to conflict violence during pregnancy and the risks of miscarriage, stillbirth, and perinatal mortality has not been studied empirically using rigorous methods and appropriate data. We investigated the association between reduced exposure to conflict violence during pregnancy and the risks of adverse pregnancy outcomes in Colombia.

METHODS AND FINDINGS

We adopted a regression discontinuity (RD) design using the July 20, 2015 cease-fire declared during the Colombian peace process as an exogenous discontinuous change in exposure to conflict events during pregnancy, comparing women with conception dates before and after the cease-fire date. We constructed the cohorts of all pregnant women in Colombia for each day between January 1, 2013 and December 31, 2017 using birth and death certificates. A total of 3,254,696 women were followed until the end of pregnancy. We measured conflict exposure as the total number of conflict events that occurred in the municipality where a pregnant woman lived during her pregnancy. We first assessed whether the cease-fire did induce a discontinuous fall in conflict exposure for women with conception dates after the cease-fire to then estimate the association of this reduced exposure with the risks of miscarriage, stillbirth, and perinatal mortality. We found that the July 20, 2015 cease-fire was associated with a reduction of the average number of conflict events (from 2.64 to 2.40) to which women were exposed during pregnancy in their municipalities of residence (mean differences -0.24; 95% confidence interval [CI] -0.35 to -0.13; p < 0.001). This association was greater in municipalities where Fuerzas Armadas Revolucionarias de Colombia (FARC) had a greater presence historically. The reduction in average exposure to conflict violence was, in turn, associated with a decrease of 9.53 stillbirths per 1,000 pregnancies (95% CI -16.13 to -2.93; p = 0.005) for municipalities with total number of FARC-related violent events above the 90th percentile of the distribution of FARC-related conflict events and a decrease of 7.57 stillbirths per 1,000 pregnancies (95% CI -13.14 to -2.00; p = 0.01) for municipalities with total number of FARC-related violent events above the 75th percentile of FARC-related events. For perinatal mortality, we found associated reductions of 10.69 (95% CI -18.32 to -3.05; p = 0.01) and 6.86 (95% CI -13.24 to -0.48; p = 0.04) deaths per 1,000 pregnancies for the 2 types of municipalities, respectively. We found no association with miscarriages. Formal tests support the validity of the key RD assumptions in our data, while a battery of sensitivity analyses and falsification tests confirm the robustness of our empirical results. The main limitations of the study are the retrospective nature of the information sources and the potential for conflict exposure misclassification.

CONCLUSIONS

Our study offers evidence that reduced exposure to conflict violence during pregnancy is associated with important (previously unmeasured) benefits in terms of reducing the risk of stillbirth and perinatal deaths. The findings are consistent with such beneficial associations manifesting themselves mainly through reduced violence exposure during the early stages of pregnancy. Beyond the relevance of this evidence for other countries beset by chronic armed conflicts, our results suggest that the fledgling Colombian peace process may be already contributing to better population health.

Miscarriage matters: the epidemiological, physical, psychological, and economic costs of early pregnancy loss

Miscarriage is generally defined as the loss of a pregnancy before viability. An estimated 23 million miscarriages occur every year worldwide, translating to 44 pregnancy losses each minute. The pooled risk of miscarriage is 15·3% (95% CI 12·5-18·7%) of all recognised pregnancies. The population prevalence of women who have had one miscarriage is 10·8% (10·3-11·4%), two miscarriages is 1·9% (1·8-2·1%), and three or more miscarriages is 0·7% (0·5-0·8%). Risk factors for miscarriage include very young or older female age (younger than 20 years and older than 35 years), older male age (older than 40 years), very low or very high body-mass index, Black ethnicity, previous miscarriages, smoking, alcohol, stress, working night shifts, air pollution, and exposure to pesticides. The consequences of miscarriage are both physical, such as bleeding or infection, and psychological. Psychological consequences include increases in the risk of anxiety, depression, post-traumatic stress disorder, and suicide. Miscarriage, and especially recurrent miscarriage, is also a sentinel risk marker for obstetric complications, including preterm birth, fetal growth restriction, placental abruption, and stillbirth in future pregnancies, and a predictor of longer-term health problems, such as cardiovascular disease and venous thromboembolism. The costs of miscarriage affect individuals, health-care systems, and society. The short-term national economic cost of miscarriage is estimated to be £471 million per year in the UK. As recurrent miscarriage is a sentinel marker for various obstetric risks in future pregnancies, women should receive care in preconception and obstetric clinics specialising in patients at high risk. As psychological morbidity is common after pregnancy loss, effective screening instruments and treatment options for mental health consequences of miscarriage need to be available. We recommend that miscarriage data are gathered and reported to facilitate comparison of rates among countries, to accelerate research, and to improve patient care and policy development.

Bias due to Selection on Live Births in Studies of Environmental Exposures during Pregnancy: A Simulation Study

BACKGROUND

Studies of the effects of prenatal environmental exposures on postnatal outcomes are particularly vulnerable to live birth bias; i.e., the bias that arises from the necessary restriction of the analysis to live births when that is influenced by both the exposure under study A and unmeasured factors U that also affect the outcome.

OBJECTIVES

In the context of a recent publication of nitrogen dioxide (NO2) and autism spectrum disorder (ASD) that found an odds ratio (OR) of 0.77 per 5.85 ppb NO2 during pregnancy, we aimed to examine what parameters would be needed to account for this protective association through live birth bias.

METHODS

We simulated the magnitude of bias under two selection mechanisms and when both mechanisms co-occur, assuming a true null effect. Simulation input parameters were based on characteristics of the original study and a range of plausible values for the prevalence of unmeasured factor U and the ORs for the selection effects (i.e., the effects of NO2 and U on loss and of U on ASD). Each scenario was simulated 1,000 times.

RESULTS

We found that the magnitude of bias was small when NO2 and U independently influenced pregnancy loss (collider-stratification without interaction), was stronger when NO2-induced loss preferentially occurred in U=1 (depletion of susceptibles), and was strongest when both mechanisms worked together. For example, ORs of 3.0 for NO2-loss, U-loss, U-ASD, and U prevalence=0.75 yielded NO2-ASD ORs per 5.85 ppb NO2 of 0.95, 0.89, and 0.75 for the three scenarios, respectively. The bias is amplified with multiple Us, yielding ORs as low as 0.51.

DISCUSSION

Our simulations illustrate that live birth bias may lead to exposure-outcome associations that are biased downward, where the extent of the bias depends on the fetal selection mechanism, the strength of that selection, and the prevalence of U. https://doi.org/10.1289/EHP7961.

COVID-19 pandemic effect on early pregnancy: are miscarriage rates altered, in asymptomatic women?

PURPOSE

To evaluate the effect of the COVID-19 pandemic state on early, first-trimester pregnancies.

METHODS

A retrospective cohort study conducted at a university-affiliated fertility center in Montreal, Quebec, since the COVID-19 shut down, March 13 until May 6, 2020. Included: all women who came for a first-trimester viability scan during the study period (Study group) and between March 1, 2019 and May 17, 2019, approximately one year prior (Control). The study population denied symptoms of COVID-19. We reviewed all first trimester scans. Early first-trimester pregnancy outcomes (Viable pregnancy, arrested pregnancy including biochemical pregnancy loss and miscarriage, and ectopic pregnancy) were measured as total number and percentage. A multivariate analysis was performed to control for other potentially significant variables, as was a power analysis supporting sample size.

RESULTS

113 women came for a first-trimester viability scan in the study period, and 172 in the control period (5-11 weeks gestational age), mean maternal age 36.5 ± 4.5 and 37.2 ± 5.4 years (p = 0.28). Viable clinical pregnancy rate was not different between the two groups (76.1 vs. 80.2% in the pandemic and pre-pandemic groups p = 0.41). No significant difference was seen in the total number of arrested pregnancies (defined as the sum of biochemical, 1st trimester miscarriages, and blighted ova) (22.1 vs. 16.9% p = 0.32), or in each type of miscarriage.

CONCLUSION

The COVID-19 pandemic environment does not seem to affect early first-trimester miscarriage rates in asymptomatic patients.

Association between prenatal exposure to a 1-month period of repeated rocket attacks and neuropsychiatric outcomes up through age 9: a retrospective cohort study

Exposure to gestational stress is implicated in increased risk for neuropsychiatric disorders in offspring. We assessed association between prenatal exposure to a 1-month period of repeated rocket attacks during the 2006 Second Lebanon War in Northern Israel and emergence of childhood neuropsychiatric disorders from birth through 9 years of age. Children born to women who were pregnant during the war (N = 6999) were identified and compared to children in the same district born a year later (N = 7054), whose mothers were not exposed to rocket attacks during pregnancy. Multivariable regression models assessed risk for attention deficit hyperactivity disorder, autism, epilepsy, depression and/or anxiety, or any of these disorders (composite outcome) in offspring. Models controlled for multiple confounders including parents' demographics, parity, maternal use of psychotropic medications during pregnancy, post-partum depression and parental psychiatric history. Results show that exposed and comparison groups did not differ with respect to demographics, parity or psychiatric history. Exposed and comparison groups were similar with regard to gestational age and weight at birth. Multivariable models did not demonstrate an association between exposure to rocket attacks during pregnancy and neuropsychiatric outcomes by age 9. No interactions were found between exposure and gestational trimester at exposure or child's sex. Our findings suggest that in utero exposure to isolated, 1-month repeated rocket attacks on a civilian population was not associated with major neuropsychiatric outcomes in children by age 9. Future studies should evaluate whether this exposure is associated with psychiatric and/or other health-related outcomes later in life.

The complex Impact of Five Years of Stress Related to Life-Threatening Events on Pregnancy Outcomes: A Preliminary Retrospective Study

Objective:

To study the impact of chronic, life-threatening stressors in the form of daily missile attacks, for five consecutive years, on pregnancy outcomes.

Method:

Charts of deliveries from two neighboring towns in the south of Israel, covering the years 2000 and 2003–2008, were reviewed retrospectively. One city had been exposed to missile attacks, while the other was not. For each year, 100 charts were chosen at random.

Results:

Significant association was found between exposure to stress and frequency of pregnancy complications (P = 0.047) and premature membrane rupture (P = 0.029). A more detailed analysis, based on dividing the stressful years into three distinct periods: early (2003–2004), intermediate (2005–2006) and late (2007–2008), revealed that preterm deliveries were significantly more frequent (P = 0.044) during the intermediate period, as was premature membrane rupture during the late period (P = 0.014).

Conclusion:

Exposure to chronic life-threatening stress resulted in more pregnancy complications and in particular more premature membrane ruptures. The impact was most significant during the middle period of the 5-year-exposure to the stressor. Hence it seems that factors of duration and habituation may play a role in the impact of chronic, life-threatening stressors on pregnancy.

Association of Prenatal Maternal Psychological Distress With Fetal Brain Growth, Metabolism, and Cortical Maturation

IMPORTANCE

Prenatal maternal stress is increasingly associated with adverse outcomes in pregnant women and their offspring. However, the association between maternal stress and human fetal brain growth and metabolism is unknown.

OBJECTIVE

To identify the association between prenatal maternal psychological distress and fetal brain growth, cortical maturation, and biochemical development using advanced 3-dimensional volumetric magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1H-MRS).

DESIGN, SETTING, AND PARTICIPANTS

This cohort study prospectively recruited pregnant women from low-risk obstetric clinics in Washington, DC, from January 1, 2016, to April 17, 2019. Participants were healthy volunteers with a normal prenatal medical history, no chronic or pregnancy-induced physical or mental illnesses, and normal results on fetal ultrasonography and biometry studies. Fetal brain MRI studies were performed at 2 time points between 24 and 40 weeks' gestation.

EXPOSURES

Prenatal maternal stress, anxiety, and depression.

MAIN OUTCOMES AND MEASURES

Volumes of fetal total brain, cortical gray matter, white matter, deep gray matter, cerebellum, brainstem, and hippocampus were measured from 3-dimensional reconstructed T2-weighted MRI scans. Cortical folding measurements included local gyrification index, sulcal depth, and curvedness. Fetal brain N-acetylaspartate, creatine, and choline levels were quantified using 1H-MRS. Maternal stress, depression, and anxiety were measured with the Perceived Stress Scale (PSS), Edinburgh Postnatal Depression Scale (EPDS), Spielberger State Anxiety Inventory (SSAI), and Spielberger Trait Anxiety Inventory (STAI).

RESULTS

A total of 193 MRI studies were performed in 119 pregnant women (67 [56%] carrying male fetuses and 52 [44%], female fetuses; maternal mean [SD] age, 34.46 [5.95] years) between 24 and 40 gestational weeks. All women were high school graduates, 99 (83%) were college graduates, and 100 (84%) reported professional employment. Thirty-two women (27%) had positive scores for stress, 31 (26%) for anxiety, and 13 (11%) for depression. Maternal trait anxiety was associated with smaller fetal left hippocampal volume (STAI score: -0.002 cm3; 95% CI, -0.003 to -0.0008 cm3; P = .004). Maternal anxiety and stress were associated with increased fetal cortical gyrification in the frontal lobe (β for SSAI score: 0.004 [95% CI, 0.001-0.006; P = .002]; β for STAI score: 0.004 [95% CI, 0.002-0.006; P < .001]; β for PSS score: 0.005 [95% CI, 0.001-0.008; P = .005]) and temporal lobe (β for SSAI score: 0.004 [95% CI, 0.001-0.007; P = .004]; β for STAI score: 0.004 [95% CI, 0.0008-0.006; P = .01]). Elevated maternal depression was associated with decreased creatine (EPDS score: -0.04; 95% CI, -0.06 to -0.02; P = .005) and choline (EPDS score: -0.03; 95% CI, -0.05 to -0.01; P = .02) levels in the fetal brain.

CONCLUSIONS AND RELEVANCE

This study found that the prevalence of maternal psychological distress in healthy, well-educated, and employed pregnant women was high, underappreciated, and associated with impaired fetal brain biochemistry and hippocampal growth as well as accelerated cortical folding. These findings appear to support the need for routine mental health surveillance for all pregnant women and targeted interventions in women with elevated psychological distress.

Spontaneous and repeat spontaneous abortion risk in relation to occupational characteristics among working Korean women: a cross-sectional analysis of nationally representative data from Korea

Background

The association between spontaneous abortion (SA) and occupational characteristics among working women is not well-studied. This study aimed to assess the risk of SA and occupational factors such as occupational classification, working hours, and work schedules among working Korean women aged > 19 years.

Methods

In this cross-sectional study, 4078 working women were identified from among 25,534 workers in the Korea National Health and Nutrition Examination Surveys V (2010–2012) database, to obtain data on SA history and the number of SAs. Odds ratios (ORs) and 95% confidence intervals (CIs) for SA were calculated using multiple logistic regression models after adjusting for age, education, household income, cigarette smoking, alcohol consumption, and obesity status. The weighted prevalence for the number of SAs was calculated according to occupational characteristics to demonstrate the SA status among working Korean women.

Results

SA occurrence was reported in 5.7% of the study participants. The ORs (95% CIs) for SA were significantly higher in pink-, green-, and blue-collared workers than in white-collared workers. Regarding weekly working hours, compared with ≤50 h spent working, the ORs (95% CIs) for 51–60, 61–70, and > 70 h per week were 1.26 (0.87–1.84), 1.63 (1.04–2.56), and 1.73 (1.10–2.70), respectively. A significantly higher weighted prevalence of repeat SAs was observed in pink- and green-collared workers and in those who worked long hours.

Conclusion

We found a significant association between SA, repeat SA, and occupational characteristics among working Korean women.

Use of Prescribed Psychotropics during Pregnancy: A Systematic Review of Pregnancy, Neonatal, and Childhood Outcomes

This paper reviews the findings from preclinical animal and human clinical research investigating maternal/fetal, neonatal, and child neurodevelopmental outcomes following prenatal exposure to psychotropic drugs. Evidence for the risks associated with prenatal exposure was examined, including teratogenicity, neurodevelopmental effects, neonatal toxicity, and long-term neurobehavioral consequences (i.e., behavioral teratogenicity). We conducted a comprehensive review of the recent results and conclusions of original research and reviews, respectively, which have investigated the short- and long-term impact of drugs commonly prescribed to pregnant women for psychological disorders, including mood, anxiety, and sleep disorders. Because mental illness in the mother is not a benign event, and may itself pose significant risks to both mother and child, simply discontinuing or avoiding medication use during pregnancy may not be possible. Therefore, prenatal exposure to psychotropic drugs is a major public health concern. Decisions regarding drug choice, dose, and duration should be made carefully, by balancing severity, chronicity, and co-morbidity of the mental illness, disorder, or condition against the potential risk for adverse outcomes due to drug exposure. Globally, maternal mental health problems are considered as a major public health challenge, which requires a stronger focus on mental health services that will benefit both mother and child. More preclinical and clinical research is needed in order to make well-informed decisions, understanding the risks associated with the use of psychotropic medications during pregnancy.

WAIMH position paper: Infants' rights in wartime

The World Association for Infant Mental Health (WAIMH) decided to compose a position paper on infants' rights in wartime, as there is still a general lack of attention paid to the impact of war-related traumas on infants' development and psychological health. Though there are numerous areas of violent conflicts around the globe, there have been few published studies that relate specifically to infants. Consequently, humanitarian aid programs tend to overlook infants' psychological needs and to pay more attention to those of older children. This position paper first reviews the studies identified through a literature search, about the impact of war-related traumas during pregnancy and postnatal periods, then describes the existing recommendations that have been added to the Children Rights Convention and their implications for infant mental health clinicians.

Impact on pregnancy outcomes of exposure to military stress during the first or second trimester as compared with the third trimester

OBJECTIVE

To compare pregnancy outcomes after exposure to military stress in different trimesters of pregnancy.

METHODS

A retrospective study of medical records of deliveries in the Wolfson (WMC) and Barzilai (BMC) medical centers in Israel between July 2014 and April 2015. All parturients were exposed to military stress for 51 days during pregnancy. Pregnancy outcomes were compared between those exposed to military stress in the first or second trimester, and those exposed in the third trimester. Outcomes were also compared between WMC (a new-onset military stress exposure area) and BMC (a chronic military stress exposure area).

RESULTS

At WMC, women exposed in the first or second trimester (n=2657) had a higher rate of preterm delivery (<37 weeks) as compared with those exposed in the third trimester (n=2037; 214 [8.1%] vs 121 [5.9%]; P=0.005). At BMC, women exposed in the first or second trimester (n=2208) had a tendency toward lower rates of diabetes mellitus (P=0.055) and macrosomia [103 (4.7%) vs 84 (6.3%); P=0.037], as compared with those exposed in the third trimester (n=1337).

CONCLUSION

Exposure to military stress during pregnancy had different impacts on pregnancy outcomes, depending on the time of exposure and whether continuous exposure to stress occurred.

Live-Birth Bias and Observed Associations Between Air Pollution and Autism

A recent analysis found that exposure to air pollution during specific weeks of pregnancy was negatively associated with risk of autism spectrum disorder (ASD) when mutually adjusted for postnatal air-pollution exposure. In this commentary, we describe 2 possible selection-bias processes that might lead to such results, both related to live-birth bias (i.e., the inevitable restriction of the analyzed sample to live births). The first mechanism is described using a directed acyclic graph and relates to the chance of live birth being a common consequence of both exposure to air pollution and another risk factor of ASD. The second mechanism involves preferential depletion of fetuses susceptible to ASD in the higher air-pollution exposure group. We further discuss the assumptions underlying these processes and their causal structures, their plausibility, and other studies where similar phenomena might have occurred.

Application of chromosomal microarray analysis in products of miscarriage

Background

Chromosomal abnormality is one of the major cause of spontaneous abortion. Most available guidelines suggest genetic testing after three miscarriages, which has been proved to be difficult to adhere to and somewhat of low cost-effectiveness. As chromosomal microarray analysis has been recommended to be applied on miscarriage products, we managed a retrospective study on our experience investigate the potential impact of this technique on previous guidelines and our present management on miscarried couples and products.

Results

Of the 405 products of conceptions, the overall detection rate of pathogenetic results was 55.3% (224/405), including 7.1% (16/224) copy number changes which could be missed by conventional karyotyping analysis. Of the 222 natural conception samples, abnormal genetic results were found in 126 cases (56.8%). The detection rate in the assistant reproductive treatment group was 53.6% (98/183). No significant difference was found between these two groups (p = 0.645, OR = 1.110 with 95% CI: 0.713–1.726). The detection rate was 53.2% (75/141) in 141 product-of-conceptions (POCs) of mothers with adverse pregnancy histories. Of the 264 POC samples of mothers without abnormal pregnancy histories, 56.4% (149/264) were genetically abnormal. The detection rate and maternal age between these two groups were all compatible.

Conclusions

Chromosomal microarray testing should be referred to couples at their first miscarriage regardless of the way how they get pregnant.

Weathering the storm; a review of pre-pregnancy stress and risk of spontaneous abortion

The Weathering Effect is a theory that links stress exposure, over the life-course, with racial disparities in reproductive outcomes, through the effects of social adversity on a woman's body. The concept of maternal "weathering" captures cumulative somatic and psychological adversities that can exacerbate the effects of aging. Much of the evidence for weathering comes from observational studies linking self-report measures with reproductive outcomes. The purpose of this review is to explore biological mechanisms that underlie these observations. We focus on spontaneous abortion because this event is understudied despite evidence of racial disparities in this outcome. Spontaneous abortion is the most common pregnancy failure, and it happens early in pregnancy. Early pregnancy is a time most susceptible to the harmful effects of immune dysregulation that may, in part, result from adversities experienced before pregnancy begins. In exploring these mechanisms, we draw on well-defined signaling processes observed in the stressor-depression relationship. Pro-inflammatory dysregulation, for example, has particular relevance to immunological control occurring early in pregnancy. Early pregnancy immunologic changes affect the trajectories of pregnancy via control of trophoblastic invasion. Within the first few weeks of pregnancy, uterine derived cytokines operate within cytokine networks and play a critical role in this invasion. Programming for pro-inflammatory dysregulation can occur before conception. This dysregulation, brought into early pregnancy, has implications for viability and success of the index pregnancy. These patterns suggest early pregnancy health is susceptible to stress processing pathways that influence this immunologic control in the first six to eight weeks of pregnancy. In this review, we discuss the known mediating role of immune factors in the stressor-depression relationship. We also discuss how adversity experienced before the index pregnancy, or "pre-pregnancy" may influence these pathways, and subsequently influence early pregnancy health. There is a need to understand adversity, experienced before pregnancy, and mechanisms driving the effects of these experiences on pregnancy outcomes. This approach is a useful entry point for understanding racial inequities in pregnancy health through an understanding of differences in exposures to adversity. We hypothesize that spontaneous abortion involves cyclical changes within a woman's reproductive tract in response to stressors that are established well before a woman enters into pregnancy. Furthermore, we propose mechanisms that potentially drive weathering processes relevant to reproductive disparities. We also examine what is known about pre-pregnancy stress exposures associated with race, inequity, and adversity, and their potential impact on neuroendocrine and immune changes affecting early pregnancy risk.

Death Is Not the End: A Register-Based Study of the Effect of Parental Death on Adult Children's Childbearing Behavior in Sweden

Macro-level studies have shown that rapid increases in mortality can affect fertility rates. Parental death has also been linked to negative psychological and physical outcomes, reduced relationship quality, and making bereaved children attach more importance to their families. No prior study has examined whether parental death influences adult children's fertility at the microlevel. This study applies event history techniques to Swedish multigeneration registers listing 1.5 million individuals with micro data on mortality and fertility to investigate short-term (first birth risk) and long-term (childlessness at age 45) effects of parental death on adult children's fertility. The principal finding is that parental death during reproductive age affects children's fertility and this effect is mainly short term. The effects differ to some degree between men and women and depend on the stage of the life course in which the bereavement occurs. Younger individuals experiencing a parental death have a significantly higher first birth risk after the parental death compared with peers who did not experience a parental death. Individuals older than 23 who experience a parental death have no or lower first birth risk after the parental death compared with baseline. Men, compared with women, are more likely to end childless if they experience a parental death.

Adverse effects of exposure to armed conflict on pregnancy: a systematic review

Introduction

Exposure to armed conflict has manifold implications for both military and civilian populations. Prenatal stress has detrimental effects on both obstetric outcomes, fetal development and the development of an individual later in life. As well as causing stress to the mother, armed conflicts can decimate local infrastructures making it increasingly difficult to access antenatal and general healthcare. The present review is particularly salient in light of the many ongoing current conflicts. It examines the impacts of exposure to armed conflicts on the pregnancy outcomes.

Methods

A thorough literature search was carried out on three databases using MeSH and truncation terms. 13 studies were included in the final analysis relating to mothers exposed to armed conflicts since 1990.

Results

The studies include data from 1 172 151 patients: mothers from Libya, Bosnia, Herzegovina, Israel, Palestine, Kosovo, Yugoslavia, Nepal, Somalia, Iraq, Kuwait and Afghanistan. There is evidence of an increased risk of mothers giving birth to babies of low birth weight as reported in nine included studies. All have a degree of bias, with four at lower and five at higher risk of bias, either not adjusting for confounders or not employing robust measures of exposure to conflict. Further evidence suggested an increase in the incidence of miscarriage, stillbirth, prematurity, congenital abnormalities, miscarriage and premature rupture of membranes among mothers exposed to armed conflict.

Conclusion

Despite the varying degrees of bias which must be considered for the available evidence, the data with the lowest risk of bias suggest a relationship between exposure to armed conflict and low birth weight. In light of the current level of displacement experienced by such populations, the identification of pregnancies at risk could improve the efficacy of antenatal care. Clinicians should consider additional ultrasound scanning where appropriate to monitor for restricted growth in such pregnancies.

Reproductive suppression follows threats to child survival

Natural selection presumably conserved mechanisms that allow females to block or terminate gestation when environmental circumstances threaten the survival of offspring. One example of this adaptive reproductive suppression, the Bruce effect, has been identified in several species, both in the laboratory and in the wild. Although descriptive epidemiology reports low fertility among women experiencing stressful circumstances, attempts to detect a Bruce effect in humans have been rare and limited. We contribute to this limited work by examining the relationship between the odds of child death and the sex ratio at birth in Sweden for the years 1751-1840. We find evidence of a generalized Bruce effect in humans in that unexpected changes in child mortality predict opposite unexpected changes in the secondary sex ratio in the following year, even after adjusting for period life expectancy. Our analysis broadens the scope of the Bruce effect literature to include humans, suggesting that women, through noncognitive decisional biology, adjust reproductive strategies and investments in response to changing environmental conditions.

Prenatal maternal bereavement and mortality in the first decades of life: a nationwide cohort study from Denmark and Sweden

BACKGROUND

The loss of a close relative is one of the most stressful life events. In pregnancy, this experience has been associated with a higher risk of fetal death and under-five mortality, but little is known about potential effects on long-term mortality in offspring. We examined the association between prenatal maternal bereavement and mortality in a cohort of 5.3 million children followed until up to 37 years of age.

METHOD

The population-based cohort study included 5 253 508 live singleton births in Denmark (1973-2004) and Sweden (1973-2006). Children born to mothers who lost a child, spouse, sibling, or parent during or 1 year before pregnancy were categorized as exposed.

RESULTS

Prenatal maternal bereavement was associated with a 10% increased all-cause mortality risk in offspring [mortality rate ratio (MRR) 1.10, 95% confidence interval (CI) 1.03-1.18]. The association was the most pronounced for children of mothers who lost a child/spouse (MRR 1.28, 95% CI 1.14-1.44) and was stronger during the first 10 years of life. Prenatal maternal bereavement may have stronger effects on natural causes of death in offspring, including infectious/parasitic disease (MRR 1.86, 95% CI 1.07-3.23), endocrine/nutritional/metabolic diseases (MRR 3.23, 95% CI 2.02-5.17), diseases of nervous system (MRR 3.36, 95% CI 2.47-4.58), and congenital malformations (MRR 1.39, 95% CI 1.08-1.80). No excess mortality risk in offspring was observed for unnatural causes of death.

CONCLUSION

Prenatal maternal bereavement was associated with an increased long-term mortality risk in offspring, particularly for selected natural causes of diseases and medical conditions. Our results support the fetal programming hypothesis that prenatal stress may contribute to ill health from physical diseases later in life.

Psychosocial Stress During First Pregnancy Predicts Infant Health Outcomes in the First Postnatal Year

OBJECTIVES

To evaluate the impact of psychosocial stress during pregnancy on infant health outcomes in the first postnatal year.

METHODS

A sample of 3000 women completed a stress inventory (the Psychosocial Hassles Scale) during their third trimester before first childbirth. Infant health outcomes were measured via maternal report at 1, 6 and 12 months postpartum. Poisson regression was used to model the effect of maternal stress during pregnancy on infant health outcomes in the first year, controlling for age, race/ethnicity, education, insurance coverage, marital status, and cigarette smoking during pregnancy.

RESULTS

Women who were younger, minority, unmarried, publicly insured and without a college degree were more likely to report high levels of prenatal stress. High prenatal stress was a significant predictor of maternal reporting of gastrointestinal illness (p < 0.0001), respiratory illness (p = 0.025), and total illness in the first year (p < 0.0001). High prenatal stress was also a significant predictor of urgent care visits (p < 0.0001) and emergency department visits (p = 0.001). It was not a significant predictor of hospitalizations (p = 0.36).

CONCLUSIONS

Maternal prenatal stress is associated with increased maternal reporting of infant illness, as well as increased frequency of both urgent care visits and emergency department visits.

Spontaneous Pregnancy Loss in Denmark Following Economic Downturns

An estimated 11%-20% of clinically recognized pregnancies result in spontaneous abortion. The literature finds elevated risk of spontaneous abortion among women who report adverse financial life events. This work suggests that, at the population level, national economic decline-an ambient and plausibly unexpected stressor-will precede an increase in spontaneous abortion. We tested this hypothesis using high-quality information on pregnancy and spontaneous loss for all women in Denmark. We applied time-series methods to monthly counts of clinically detected spontaneous abortions (n = 157,449) and the unemployment rate in Denmark beginning in January 1995 and ending in December 2009. Our statistical methods controlled for temporal patterns in spontaneous abortion (e.g., seasonality, trend) and changes in the population of pregnancies at risk of loss. Unexpected increases in the unemployment rate preceded by 1 month a rise in the number of spontaneous abortions (β = 33.19 losses/month, 95% confidence interval: 8.71, 57.67). An attendant analysis that used consumption of durable household goods as an indicator of financial insecurity supported the inference from our main test. Changes over time in elective abortions and in the cohort composition of high-risk pregnancies did not account for results. It appears that in Denmark, ambient stressors as common as increasing unemployment may precede a population-level increase in spontaneous abortion.

Preconception Maternal Bereavement and Infant and Childhood Mortality: A Danish Population-Based Study

OBJECTIVES

Preconception maternal bereavement may be associated with an increased risk for infant mortality, although these previously reported findings have not been replicated. We sought to examine if the association could be replicated and explore if risk extended into childhood.

METHODS

Using a Danish population-based sample of offspring born 1979 to 2009 (N = 1,865,454), we analyzed neonatal (0-28 days), postneonatal infant (29-364 days), and early childhood (1-5 years) mortality after maternal bereavement in the preconception (6-0 months before pregnancy) and prenatal (between conception and birth) periods. Maternal bereavement was defined as death of a first-degree relative of the mother. Analyses were conducted using logistic and log-linear Poisson regressions that were adjusted for offspring, mother, and father sociodemographic and health factors.

RESULTS

We identified 6541 (0.004%) neonates, 3538 (0.002%) postneonates, and 2132 (0.001%) children between the ages of 1 and 5 years who died. After adjusting for covariates, bereavement during the preconception period was associated with increased odds of neonatal (adjusted odds ratio = 1.87, 95% confidence interval = 1.53-2.30) and postneonatal infant mortality (adjusted odds ratio = 1.52, 95% confidence interval = 1.15-2.02). Associations were timing specific (6 months before pregnancy only) and consistent across sensitivity analyses. Bereavement during the prenatal period was not consistently associated with increased risk of offspring mortality; however, this may reflect relatively low statistical power.

CONCLUSIONS

Results support and extend previous findings linking bereavement during the preconception period with increased odds of early offspring mortality. The period immediately before pregnancy may be a sensitive period with potential etiological implications and ramifications for offspring mortality.

A mass shooting at Port Arthur, Tasmania, Australia: a study of its impact on early pregnancy losses using a conception time-based methodology

STUDY QUESTION

Does an acute calamity in a community cause early miscarriage and is this association the same for male and female fetuses?

SUMMARY ANSWER

Estimated losses of 29.5% of first trimester pregnancies in the affected region could be associated with an acute calamity, with no statistically significant difference in estimated losses by fetal sex.

WHAT IS KNOWN ALREADY

There are very few studies on the impact of a calamity on early pregnancy loss and its differential effects on male and female fetuses. A decline in the human sex ratio at birth associated with the events of 9/11 in New York has been documented.

STUDY DESIGN, SIZE, DURATION

This is a retrospective descriptive study of birth register data in Tasmania, Australia, from 1991 to 1997, covering the period in which the calamity occurred. The register contains data on all pregnancies that proceeded to >20 weeks gestation. The conception date was calculated by subtracting gestational age from birth date. We estimated that 40 318 pregnancies were conceived in the period 1991-1996 inclusive. These were aggregated to 4-weekly blocks classified by region and sex.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The acute calamity was at Port Arthur, Tasmania, Australia. On 28 April 1996, a gunman opened fire on visitors and staff in a tourist cafe. A very stressful 20 h period, ended with 35 people dead and 22 injured. A negative binomial regression model was used to assess the association between this calamity and pregnancy loss. This loss is evidenced by a shortfall in the registration of pregnancies that were in their first trimester at the time of the calamity.

MAIN RESULTS AND THE ROLE OF CHANCE

We estimated a shortfall of 29.5% or 229 registered pregnancies among those in the first trimester at the time of the calamity (P < 0.001), in the region surrounding the calamity site. There was no sex effect in this shortfall (P = 0.911). There was no corresponding shortfall in other parts of Tasmania (P = 0.349).

LIMITATIONS, REASONS FOR CAUTION

The study is descriptive and cannot produce causal inferences. These first trimester miscarriages are estimated statistically and it is understood that gestational age is an estimate. The use of maternal residential postcodes at birth as a surrogate for geographic area or space assumes that the mother has not moved into the postcode area after the calamity and before the reporting of a birth.

WIDER IMPLICATIONS OF THE FINDINGS

The results of this study suggest that calamities bring about significant pregnancy loss affecting both sexes. The methodology presented of inferring conception date from birth date and using this for analysis, provides a more accurate assessment of first trimester pregnancy losses than raw birth data or sex ratio at birth.

Stress During Pregnancy

High levels of stress during pregnancy are associated with a number of adverse psychological and physiological outcomes for mother and child. These effects seem to be transmitted in part by one of the major stress-responsive systems, namely the hypothalamic-pituitary-adrenal (HPA) axis, which includes the hormone cortisol. However, as inconsistent study results indicate, methodology poses a substantial challenge to the investigation of stress during pregnancy. For example, although measures of maternal psychological stress and stress hormones are independently related to adverse pregnancy outcome, they seldom have been found to correlate with one another directly. Repeated measurement of psychological and biological responses to acute standardized stress challenges appears to reveal stronger associations. This article reviews the literature on experienced stress and stress hormones in pregnant women and presents studies that used standardized stress challenges (e.g., the Trier Social Stress Test, the cortisol response to morning awakening) to examine maternal stress reactivity more systematically. This review also takes a look at the few studies that examined the protective effects of psychological and psychosocial resources or stress interventions on experienced stress and stress hormones in pregnant women. Overall, results indicate that baseline stress hormone levels advance incrementally during gestation, presumably to prepare mother and fetus for delivery, while responses to acute stress appear to be increasingly attenuated. Moreover, the acute maternal stress response seems to be predictive of neonatal birth outcome and maternal well-being postpartum. Preliminary findings also suggest that much can be done toward coping with stress during pregnancy. Further research and a closer collaboration between science and clinical practice are required.

Fetal sex modifies effects of prenatal stress exposure and adverse birth outcomes

Prenatal maternal stress is associated with pregnancy complications, poor fetal development and poor birth outcomes. Fetal sex has also been shown to affect the course of pregnancy and its outcomes. The aim of this study was to evaluate whether fetal sex modifies the association between continuous exposure to life-threatening rocket attack alarms and adverse pregnancy outcomes. A retrospective cohort study was conducted in which the exposed group was comprised of 1846 women exposed to rocket-attack alarms before and during pregnancy. The unexposed group, with similar sociodemographic characteristics, delivered during the same period of time at the same medical center, but resided out of rocket-attack range. Multivariable models for each gender separately, controlling for possible confounders, evaluated the risk associated with exposure for preterm births (PTB), low birthweight (LBW), small for gestational age and small head circumference (HC). In both univariable and multivariable analyses exposure status was a significant risk factor in female fetuses only: PTB (adj. OR = 1.43; 1.04-1.96), LBW (adj. OR = 1.41; 1.02-1.95) and HC < 31 cm (adj. OR = 1.78; 1.11-2.88). In addition, regarding all adverse outcomes, the male-to-female ratio was higher in the exposed group than in the unexposed group. The findings support the hypothesis that male and female fetuses respond differentially to chronic maternal stress.

Hypothesis: high levels of maternal adrenal androgens are a major cause of miscarriage and other forms of reproductive suboptimality

A cause is proposed for several forms of reproductive suboptimality (viz foetal loss, preterm birth and low birth weight). The point is illustrated here in the case of miscarriage. I suggest that all these forms of reproductive suboptimality are partially caused by high levels of stress-related maternal adrenal androgens. The argument is supported by both experimental and epidemiological data.