Association of prenatal maternal perceived stress with a sexually dimorphic measure of cognition in 4.5-month-old infants

Examining the association between prenatal maternal stress and infant non-nutritive suck

BACKGROUND

This study examined the relationship between prenatal maternal stress (PREMS) and non-nutritive suck (NNS) and tested its robustness across 2 demographically diverse populations.

METHODS

The study involved 2 prospective birth cohorts participating in the national Environmental influences on Child Health Outcomes (ECHO) Program: Illinois Kids Development Study (IKIDS) and ECHO Puerto Rico (ECHO-PROTECT). PREMS was measured during late pregnancy via the 10-item Perceived Stress Scale (PSS-10). NNS was sampled from 1- to 8-week-olds using a custom pacifier for ~5 min.

RESULTS

Overall, 237 mother-infant dyads completed this study. Despite several significant differences, including race/ethnicity, income, education, and PREMS levels, significant PREMS-NNS associations were found in the 2 cohorts. In adjusted linear regression models, higher PREMS, measured through PSS-10 total scores, related to fewer but longer NNS bursts per minute.

CONCLUSIONS

A significant association was observed between PREMS and NNS across two diverse cohorts. This finding is important as it may enable the earlier detection of exposure-related deficits and, as a result, earlier intervention, which potentially can optimize outcomes. More research is needed to understand how NNS affects children's neurofunction and development.

IMPACT

In this double-cohort study, we found that higher maternal perceived stress assessed in late pregnancy was significantly associated with fewer but longer sucking bursts in 1- to 8-week-old infants. This is the first study investigating the association between prenatal maternal stress (PREMS) and infant non-nutritive suck (NNS), an early indicator of central nervous system integrity. Non-nutritive suck is a potential marker of increased prenatal stress in diverse populations. Non-nutritive suck can potentially serve as an early indicator of exposure-related neuropsychological deficits allowing for earlier interventions and thus better prognoses.

Environmental Risk Factors and Cognitive Outcomes in Psychosis: Pre-, Perinatal, and Early Life Adversity

Risk for psychosis begins to accumulate as early as the fetal period through exposure to obstetric complications like fetal hypoxia, maternal stress, and prenatal infection. Stressors in the postnatal period, such as childhood trauma, peer victimization, and neighborhood-level adversity, further increase susceptibility for psychosis. Cognitive difficulties are among the first symptoms to emerge in individuals who go on to develop a psychotic disorder. We review the relationship between pre-, perinatal, and early childhood adversities and cognitive outcomes in individuals with psychosis. Current evidence shows that the aforementioned environmental risk factors may be linked to lower overall intelligence and executive dysfunction, beginning in the premorbid period and persisting into adulthood in individuals with psychosis. It is likely that early life stress contributes to cognitive difficulties in psychosis through dysregulation of the body's response to stress, causing changes such as increased cortisol levels and chronic immune activation, which can negatively impact neurodevelopment. Intersectional aspects of identity (e.g., sex/gender, race/ethnicity), as well as gene-environment interactions, likely inform the developmental cascade to cognitive difficulties throughout the course of psychotic disorders and are reviewed below. Prospective studies of birth cohorts will serve to further clarify the relationship between early-life environmental risk factors and cognitive outcomes in the developmental course of psychotic disorders. Specific methodological recommendations are provided for future research.

Associations of Prenatal Exposure to Phthalates with Measures of Cognition in 4.5-Month-Old Infants

The association of prenatal phthalate exposure with physical reasoning was assessed in 159 (78 female; 81 male) 4.5-month-old infants from a prospective cohort. Phthalate metabolites were quantified in urine from 16–18 gestational weeks and a pool of five urines from across pregnancy. Infants’ looking times to physically impossible and possible events were recorded via infrared eye-tracking. Infants that recognize that one of the events is impossible will look at that event longer. Associations of phthalate biomarkers with looking time differences (impossible–possible) were adjusted for maternal age, infant sex, and order of event presentation, and effect modification by infant sex was assessed. Each interquartile range (IQR) increase of monoethyl phthalate in the pooled sample was associated with females’ increased looking time (β = 1.0; 95%CI = 0.3, 1.7 s) to the impossible event. However, for males, an IQR increase in monoethyl phthalate at 16–18 weeks (β = −2.5; 95%CI = −4.4,−0.6 s), the sum of di(isononyl) phthalate metabolites in the pooled sample (β = −1.0; 95%CI = −1.8, −0.1 s), and the sum of all phthalate metabolites in both samples (β = −2.3; 95%CI = −4.4, −0.2 s) were associated with increased looking to the possible event, suggesting that higher prenatal phthalate exposure is associated with poorer physical reasoning in male infants.

Associations of Maternal Stress, Prenatal Exposure to Per- and Polyfluoroalkyl Substances (PFAS), and Demographic Risk Factors with Birth Outcomes and Offspring Neurodevelopment: An Overview of the ECHO.CA.IL Prospective Birth Cohorts

BACKGROUND

Infants whose mothers experience greater psychosocial stress and environmental chemical exposures during pregnancy may face greater rates of preterm birth, lower birth weight, and impaired neurodevelopment.

METHODS

ECHO.CA.IL is composed of two cohorts, Chemicals in Our Bodies (CIOB; n = 822 pregnant women and n = 286 infants) and Illinois Kids Development Study (IKIDS; n = 565 mother-infant pairs), which recruit pregnant women from San Francisco, CA and Urbana-Champaign, IL, respectively. We examined associations between demographic characteristics and gestational age, birth weight z-scores, and cognition at 7.5 months across these two cohorts using linear models. We also examined differences in biomarkers of exposure to per- and polyfluoroalkyl substances (PFAS), measured in second-trimester serum, and psychosocial stressors by cohort and participant demographics.

RESULTS

To date, these cohorts have recruited over 1300 pregnant women combined. IKIDS has mothers who are majority white (80%), whereas CIOB mothers are racially and ethnically diverse (38% white, 34% Hispanic, 17% Asian/Pacific Islander). Compared to CIOB, median levels of PFOS, a specific PFAS congener, are higher in IKIDS (2.45 ng/mL versus 1.94 ng/mL), while psychosocial stressors are higher among CIOB. Across both cohorts, women who were non-white and single had lower birth weight z-scores relative to white women and married women, respectively. Demographic characteristics are not associated with cognitive outcomes at 7.5 months.

CONCLUSIONS

This profile of the ECHO.CA.IL cohort found that mothers and their infants who vary in terms of socioeconomic status, race/ethnicity, and geographic location are similar in many of our measures of exposures and cognitive outcomes. Similar to past work, we found that non-white and single women had lower birth weight infants than white and married women. We also found differences in levels of PFOS and psychosocial stressors based on geographic location.

Associations of prenatal maternal stress with measures of cognition in 7.5-month-old infants

Studies have shown that prenatal stress can negatively impact neurodevelopment, but little is known about its effect on early cognitive development. We assessed the impact of prenatal stress on cognition in 152 7.5-month-old infants using Cohen's Perceived Stress Scale (PSS), maternal telomere length (MTL), and a Stressful Life Events (SLE) Scale. A visual recognition memory task consisting of nine blocks, each with one familiarization trial (two identical stimuli) followed by two test trials (one familiar stimulus, one novel), was administered. Outcomes assessed included: average time looking at stimuli (measure: processing speed), time to reach looking time criterion (measure: attention), and the proportion of time looking at the novel stimulus (measure: recognition memory). We examined the association of each stress measure with each outcome adjusted for infant age and sex, which of the two stimuli in each set was novel, household income, and maternal age, education, and IQ. Higher prenatal stress was associated with shorter looking durations [PSS (β = -1.6, 95% CI: -2.5, -0.58); SLE (β = 0.58, 95% CI: -0.08, 1.24); MTL (β = 1.81, 95% CI: 0.18, 3.44)] and longer time to reach criterion [PSS (β = 9.1, 95% CI: 1.6, 16.6); SLE (β = 12.2, 95% CI: 1.9, 24.1); MTL (β = -23.1, 95% CI: -45.3, -0.9)], suggesting that higher prenatal stress is associated with decreased visual attention in infancy.