Abstract
Adverse childhood experiences (ACEs) are associated with higher rates of prenatal and postpartum depression and child socioemotional problems. This longitudinal study investigated prenatal and postpartum depression as indirect effects linking maternal ACEs to changes in toddler socioemotional problems. Mothers (n = 304) reporting their ACEs, depressive symptoms in pregnancy and 6-months postpartum, and their children’s socioemotional problems at 15-, 24-, and 35- months postpartum. Latent growth curve parallel and serial mediation analyses indicated that higher maternal ACEs were significantly associated with greater perinatal depressive symptoms. Depressive symptoms during pregnancy, but not 6-months postpartum, were associated with higher average socioemotional problems at each time point. Maternal ACEs were indirectly associated with average socioemotional problems through prenatal, but not postpartum, depressive symptoms. Indirect effects from maternal ACEs to socioemotional problem trajectories were not significant. Findings suggest that prenatal depressive symptoms should be further explored as a mechanism through which maternal ACEs impact early socioemotional problems.
Maternal mental health difficulties pose health risks to both the mother and child. Approximately 10% to 20% of women around the world experience anxiety or depression during the period spanning pregnancy to the first year postpartum (Dennis et al., 2017; Shorey et al., 2018). The COVID-19 pandemic has amplified perinatal mental health risk, with prenatal and postpartum depression prevalence rates in North America estimated between 23% and 26% (Caffieri et al., 2023). Adverse childhood experiences (ACEs) increase risk for experiencing perinatal depressive symptoms (Aydoğan et al., 2024). Both ACEs and perinatal depressive symptoms can adversely impact child socioemotional development (e.g., Madigan et al., 2018). However, the role of ACEs in elevating risk for perinatal depressive symptoms, and the unique relations between prenatal and postpartum depressive symptoms and changes in child socioemotional problems across time, has yet to be explored. This longitudinal study aims to examine whether pregnancy and postpartum depressive symptoms, occurring during the COVID-19 pandemic, link maternal ACEs and trajectories of early child socioemotional problems.
ACEs, such as abuse, neglect, and household dysfunction experienced prior to the age of 18, are strong risk factors for the development of depression during the perinatal period (e.g., Racine et al., 2020; Wajid et al., 2020). Exposure to adversity contributes to allostatic load (i.e., the wear-and-tear on the body), which can alter biological functioning of the endocrine, immune, and the central nervous systems, resulting in elevated vulnerability to mental health difficulties later in life (Atkinson et al., 2023; Buss et al., 2017). In a study by Racine et al. (2020), 62% of pregnant individuals reported exposure to at least one ACE, highlighting the prevalence of ACEs in pregnant samples. Indeed, maternal ACE severity is positively associated with perinatal depressive symptoms (e.g., Racine et al., 2020; Wajid et al., 2020). Prevalence ratios of perinatal depression increases in a dose-response manner with increases in the number of ACEs (Bränn et al., 2023). A recent meta-analysis found that maternal ACEs are positively associated with both prenatal and postpartum depression (r = .19 and r = .23, respectively; Racine et al., 2021). Thus, it is well-established that maternal ACEs pose a risk for perinatal depression.
Understanding risk for perinatal depression is important for both maternal and child health. The Developmental Origins of Health and Disease hypothesis proposes that perinatal environmental experiences have widespread long-term consequences for child health and development (Barker, 1998). Research highlights the negative effects of perinatal depression on child socioemotional difficulties (e.g., Junge et al., 2017; Madigan et al., 2018; Pietikäinen et al., 2020). A meta-analysis found that mothers with prenatal depression or anxiety had 1.5-2 times the odds of having children with behavioural difficulties compared to those not experiencing depression or anxiety (Madigan et al., 2018). Longitudinal research indicates that higher prenatal and postpartum depressive symptoms are associated with elevated socioemotional problems, including internalizing and externalizing problems in children aged 2 and 5 years (Junge et al., 2017; Pietikäinen et al., 2020). The first few years of life signify a developmental period prone to elevations in negative affect and challenges in socioemotional development (e.g., Jusiene et al., 2015). There are normative trajectories of change in socioemotional problems, with difficulties increasing and typically peaking around 2 years, followed by normative declines as self-regulation skills develop further (Fanti & Henrich, 2010; Gilliom & Shaw, 2004). However, it is unclear how prenatal and postpartum depressive symptoms predict trajectories of change in child socioemotional problems across toddlerhood.
In addition, maternal ACEs have been directly associated with offspring socioemotional difficulties (e.g., Bödeker et al., 2019; Cooke et al., 2019; Plant et al., 2018; Racine et al., 2023). Researchers have begun investigating potential mediating pathways connecting maternal ACEs and child socioemotional outcomes (for meta-analysis see Ma et al., 2022), with preliminary evidence pointing to maternal depression as one such mediating pathway. For example, maternal ACEs (maltreatment, specifically) were associated with more problematic trajectories of problem behaviour across 18, 36 and 60 months; that is, a stronger increase in internalizing problems and slower decline in externalizing problems from 18 to 60 months (Harris et al., 2023). In addition, the association between ACEs and internalizing problems (not externalizing problems) were mediated by postpartum depressive symptoms (Harris et al., 2023). However, the longitudinal studies are limited, and results are mixed, highlighting the need for more research aiming to identify indirect effects between maternal ACEs and child outcomes. Further, few of the previous studies have investigated changes in child socioemotional difficulties across time, highlighting the need to determine the temporal stability of preliminary associations in early childhood.
From a theoretical standpoint, maternal depressive symptoms during both pregnancy and the postpartum period may mediate the association between maternal ACEs and child outcomes. There are potentially distinct reasons for how depressive symptoms in pregnancy and the postpartum elevate risk for child socioemotional problems. In pregnancy, depressive symptoms can impact health-related behaviours, regularly seeking medical care, physical activity, balanced nutrition, and substance use (e.g., smoking), which could impact the developing fetus (Luong et al., 2021; Naaz & Muneshwar, 2023; Pasha et al., 2022). Prenatal depression is also associated with alterations in stress hormones and immune markers, which can cross the fetal blood-brain barrier and impact fetal development (e.g., Lubrano et al., 2024). In addition, depressive symptoms in the postpartum period may adversely impact parent-infant bonding and affective engagement and responsivity (Bödeker et al., 2019; Schmitt et al., 2024).
We will compare both parallel and serial mediation models to better understand the temporal organization of depressive symptoms across the perinatal period, and how they influence child socioemotional outcomes. First, in a parallel mediation model, depressive symptoms in pregnancy and the postpartum are distinct but correlated mediators, allowing for depression during both periods to explain the pathway from maternal ACEs to child outcomes. This is plausible as depressive symptoms at different perinatal time points may reflect shared vulnerability but have independent effects on child outcomes. Prenatal and postpartum periods involve different physiological and psychosocial challenges (e.g., hormonal changes, caregiving demands), and depressive symptoms during each period may have independent effects on infant development (Kingston et al., 2012). Second, in a serial mediation model prenatal depressive symptoms predict postpartum depressive symptoms (Liu et al., 2022), following a developmental cascade framework. The impact of maternal ACEs on child outcomes may be linked through a temporal chain, whereby maternal ACEs increases risk of prenatal depressive symptoms, which in turn, heightens the risk of postpartum depressive symptoms. Comparing these models allows us to test competing hypotheses about the structure and timing of perinatal depressive symptoms as indirect effects linking maternal ACEs to toddler socioemotional outcomes.
Environmental stressors, including the COVID-19 pandemic, exacerbate vulnerability for mental health problems (e.g., Caffieri et al., 2023). In addition, higher maternal ACEs elevated risk of postpartum depression during the COVID-19 pandemic (Kornfield et al., 2021). Further, parents with higher ACE severity experienced elevated challenges coping with parenting demands during the pandemic (e.g., Arowolo et al., 2024 review). The pandemic led to social isolation and less social support for families, potentially exacerbating the impact of both parental mental health on child socioemotional outcomes. Prior research during the pandemic links elevated depressive symptoms in pregnancy and the postpartum to early infant socioemotional problems (Duguay et al., 2022; Khoury et al., 2024). However, this literature is limited to infancy and early toddlerhood and does not extend past the first year. Taken together, there is concern that maternal ACEs may be linked to elevated pregnancy and/or postpartum depression, in the context of the COVID-19 pandemic, which, in turn, may impact developmental trajectories of socioemotional problems.
This longitudinal study conducted during the COVID-19 pandemic had three primary aims: (1) to investigate the association between maternal ACEs and perinatal depressive symptoms as well as changes in toddler socioemotional problems from 15- to 35-months postpartum; (2) to assess if prenatal and postpartum depressive symptoms are associated with toddler socioemotional problems from 15- to 35-months; and (3) to investigate the mediating role of prenatal and postpartum depressive symptoms in explaining the association between maternal ACEs and child socioemotional development, using both parallel and serial mediation models. We hypothesized that (1) higher maternal ACEs would be associated with higher levels of perinatal depressive symptoms and higher initial toddler socioemotional problems (at 15-months) as well as a steeper increase in socioemotional problems across the first three years; (2) higher perinatal depressive symptoms would similarly be associated with greater initial toddler socioemotional problems (at 15-months) and a steeper increase in socioemotional problems from age 1 to 3; and lastly, (3) perinatal depressive symptoms would mediate the link between maternal ACEs and child socioemotional difficulties. We did not put forth specific hypotheses about the differential mediating role of prenatal versus postpartum depression (though we simultaneously explored both as parallel and serial mediators).
Methods
Participants and Study Design
The COVID-19 Wellbeing and Stress Study involved participants from Ontario, Canada, who were pregnant in the spring and summer of 2020. Participants were followed until their children reached three years of age. Eligibility criteria during pregnancy included residing in Ontario, being able to read and write in English, being at least 18 years old, and being less than 36 weeks pregnant. Recruitment was conducted through social media, community postings, and word of mouth.
This paper analyzes data from five time points within the broader longitudinal study (Khoury et al., 2023) with total sample sizes as follows: pregnancy (n = 304), 6-months postpartum (n = 180), 15-months postpartum (n = 193), 24-months postpartum (n = 186), and 35-months postpartum (n = 186). Participants completed questionnaires regarding their adverse childhood experiences in pregnancy, depressive symptoms in pregnancy and 6-months postpartum, and their children’s socioemotional outcomes were assessed at 15-, 24-, and 35-months postpartum. For additional details on the full sample, refer to Khoury et al. (2023).
Sample Characteristics and Descriptive Statistics
Note. Adverse childhood experiences (ACEs) frequency based on percent endorsed.; CESD = Centre for Epidemiological Studies Depression scale; Toddler Sociomotional Outcomes measured by the Brief Infant–Toddler Social and Emotional Assessment Problem (BITSEA).
Measures
Adverse Childhood Experiences
Participants completed the 10-item Adverse Childhood Experiences (ACE) questionnaire (Felitti et al., 1998) during pregnancy. The ACE questionnaire assesses 10 different adverse childhood experiences occurring before the age of 18, including presence of emotional, physical, and sexual abuse, emotional neglect, physical neglect, domestic violence, parental separation/divorce, parental mental illness, parental substance abuse, and parental incarceration. Responses to the ACE questionnaire are recorded as dichotomous (yes, no), indicating whether the participant endorsed each ACE. The total ACE score was used in this analysis. The ACE total score correlates highly with more detailed assessments of childhood maltreatment, including the Childhood Trauma Questionnaire (CTQ) and the Maltreatment and Abuse Chronology of Exposure Scale (Schmidt et al., 2020; Teicher & Parigger, 2015).
Depressive Symptoms
Participants completed the 10-item Center for Epidemiologic Studies Depression Scale (CES-D; Andresen et al., 1993) during pregnancy and 6-months postpartum. The CES-D measures depressive symptoms over the past 7 days (example questions: “How often did you feel depressed?”, “How often did you feel hopeful about the future?”, “how often did you feel that you could not “get going”?). The CES-D total score ranges from 0 to 30, with a cut-off score of 10 or higher indicating clinically significant depressive symptoms (Andresen et al., 1993). The CES-D is a reliable and valid measure of depression in pregnant and postpartum samples (Beeghly et al., 2003). The CES-D had good internal consistency in the current sample during pregnancy and at 6-months postpartum (Cronbach’s α = .87) at both time points).
Child Socioemotional Outcomes
Child socioemotional problems were measured using the parent-reported Brief Infant–Toddler Social and Emotional Assessment (BITSEA) at 15-, 24-, and 35-months postpartum (Briggs-Gowan et al., 2006). The BITSEA consists of 42 items, with 31 items evaluating problems (Problem Scale, score range: 0–62), which was the focus of the current analyses. A continuous score from the Problem Scale was used for analysis.
COVID-19 Impact
The subjective and objective impact of the COVID-19 pandemic was assessed during T1. Subjective impact was measured using a single item (“Taking everything about COVID-19 into account, the effects of COVID-19 on me and my household have been”), rated from 1 (very positive) to 5 (very negative), with higher scores indicating greater perceived stress. This approach aligns with prior research emphasizing the importance of stress appraisal in predicting maternal and child outcomes (Khoury et al., 2021, 2023). Objective COVID impact was measured using 11 items assessing social isolation, relationship difficulties, financial changes, infection risk, and childcare challenges, rated from 1 (not at all) to 7 (a lot). These items were averaged to form an objective impact subscale. The subjective item was rescaled to a 7-point scale and averaged with the objective subscale to create a composite COVID-19 impact score, with higher values reflecting more negative experiences.
Sociodemographic Characteristics
Participants reported sociodemographic information during pregnancy (see below). In addition, after birth, participants reported infant birth weight, gestational age at birth, infant sex, and child age at time of socioemotional assessments.
Statistical Analyses
Preliminary analyses were conducted using IBM SPSS Statistics 28 to examine normality, provide descriptive statistics, and identify potential covariates. Potential covariates were included in subsequent analyses only if there were significant bivariate correlations with outcomes of interest. We examined sociodemographic variables including maternal age, education level, income, race, ethnicity, marital status, number of children, and COVID-19 impact in relation to both maternal depressive symptoms and child socioemotional outcomes. We also assessed gestational age and trimester of pregnancy, child sex, child age, and child birthweight and gestational age at birth as potential covariates in relation to child outcomes.
Analyses were conducted in Mplus 8.4 using full information maximum likelihood (FIML) estimation (Collins et al., 2001). First, a linear latent growth curve model (LGCM) was used to model changes in child BITSEA problem outcomes at 15-, 24-, and 35-months. Second, mediation analyses were conducted to assess whether the effect of maternal ACEs on toddler BITSEA outcomes was mediated by pre- and post-partum depressive symptoms. Continuous independent variables and covariates were mean-centered prior to entry into the models. For the LGCM, the BITSEA intercept was centered at the first measurement point (15-months), and the slope parameters loadings were fixed at 0, 1, 2. Thus, the intercept mean represented the average level of toddler socioemotional problems at 15-months, and the mean slope represented the average amount of estimated mean change in toddler behaviour problems between each time point. The intercept and slope variances represent individual differences in initial levels and rates of change, respectively. BITSEA residuals were constrained to be equal.
We then tested for mediation by regressing prenatal and postpartum depressive symptoms on maternal ACEs (a paths), the intercept and slope of toddler behaviour problem were regressed on prenatal and postpartum depressive symptoms (b paths), and the intercept and slope of toddler behaviour problems were regressed on ACEs (c paths, direct effect). In addition, the indirect effects between maternal ACEs and toddler behaviour problems slope and intercept were computed. Bootstrapping was used with 10,000 resamples to estimate 95% bias-corrected confidence intervals (CIs) to determine significance of direct and indirect effects. Prenatal and postpartum depressive symptoms were first assessed as simultaneous mediators and were allowed to covary in the model (Figure 1). We also conducted a second serial mediation model (Figure 2), where prenatal depressive symptoms predicted postpartum depressive symptoms, and the serial indirect effect was computed in addition to separate indirect effects through both prenatal and postpartum depressive symptoms. Control variables identified through bivariate correlations were added to both mediation models, and non-significant effects were trimmed to ensure model parsimony. Model fit was assessed using a combination of chi-square values, CFI, RMSEA, and Standardized Root Mean Square Residual (SRMR). Values >0.90 for CFI, and <0.08 for RMSEA and SRMR are indicative of acceptable model fit (Little, 2013). Latent Growth Curve Parallel Mediation Model Note: Standardized Regression Coefficients are Presented. Solid Lines Represent Significant Regression Paths (*p < .05, **p < .01); Dotted Lines Represent Non Significant Paths Latent Growth Curve Serial Mediation Model Note: Fit: χ2 (29) = 52.248, p < 0.01, RMSEA = 0.05, CFI = 0.95, SRMR = 0.07. Standardized Regression Coefficients are Presented. Solid Lines Represent Significant Regression Paths (*p < .05, **p < .01); Dotted Lines Represent Non Significant Paths

Missing Data
In total, 304 individuals participated in the study during pregnancy. For the pregnancy time point, 0.3% (n = 1) of the CES-D and 1% (n = 3) of the ACE scale were missing due to incomplete questionnaires. Missing data at subsequent time points was due to attrition. A total of 40.8% (n = 124) of the participants did not complete the CES-D at 6-months postpartum. The percentage of participants who did not complete BITSEA questionnaires at 15 months was 37.5% (n = 114), at 24 months was 39.1% (n = 119), and at 35 months was 39.5% (n = 120).
Participants who completed the follow up assessments at T2-T5 (6- to 35-months) did not differ from those who did not on parent age, ethnicity, education, or number of children (ps range = .06–.99). However, study completion varied by participant race, income, relationship status, and weeks gestation at T1. 1 No other significant differences were found in participants who completed or did not complete all time points. Variables in our dataset predicted missingness, which aligns with the Missing at Random assumption. Missing data were accounted for by FIML and the full sample size (n = 304) was used in LGCM mediation analyses. It is recommended that FIML be supplemented with auxiliary variables that predict missingness (Graham, 2009), thus participant race, income, relationship status, and weeks gestation at pregnancy assessment were included in models either as auxiliary variables or as covariates.
Results
Descriptives Statistics
See Table 1 for descriptive statistics for sociodemographics and questionnaires. In terms of maternal ACEs, 54.5% of the sample reported zero ACEs, 40.2% reported 1-3 ACEs, and 5.3% reported 4+ ACEs. A total of 27.72% during pregnancy and 22.78% at 6-months postpartum reported depressive symptoms within the clinical range. In terms of child emotional and behaviour outcomes, 21.5%, 15.1%, and 29.7 % scored in the “Possible Problem” range on the Problem scale at 15-, 24- and 35-months respectively. 2 There was one extreme outlier (>3 SD from the mean) in the BITSEA Problem scale at 24-months. This outlier was removed and estimated through FIML in subsequent growth curve analyses.
Preliminary Bivariate Correlations
As shown in Supplemental Table S2, higher maternal education was significantly associated with lower BITSEA problem scores at 15-, 24-, and 35-months. Lower family income and higher negative COVID-19 impact were significantly associated with higher depressive symptoms at T1 and T2. Of note, maternal education and income were highly correlated. COVID-19 impact and relationship status were significantly associated with BITSEA problems at 15- and 24-months, respectively. Although toddler sex was not associated with socioemotional outcomes in the current study (potentially because BITSEA scores are normed based on biological sex), prior research suggests it is an important factor to consider. Thus, relationship status, education, COVID-19 impact, and toddler sex were tested as potential covariates.
As shown by the bivariate correlations in Supplemental Table S2, maternal ACE severity was significantly correlated with depressive symptoms at T1 (r = .34) and T2 (r = .29). Maternal ACEs were also significantly correlated with child BITSEA problem scores at all time points (r range = .21-.22). Maternal depressive symptoms at T1 were significantly associated with maternal depressive symptoms at T2 (r = .58), and BITSEA problem scores at all time points (r range = .31-.32). Further, maternal depressive symptoms at T2 were significantly associated with BITSEA problem scores at all time points (r range = .24-.27). In addition, BITSEA problem scores were highly intercorrelated across time points (r range = .64-.75; Supplemental Table S2).
Latent Growth Curve Model of Changes in Toddler Socioemotional Problems
Parameter estimates for the latent growth intercept and slope are displayed in Supplemental Table S2. Individual differences in initial levels and rates of change in toddler behaviour problems were both significant. The BITSEA intercept and slope were not significantly correlated (r = .21, p = .58), indicating that initial socioemotional scores were not significantly associated with the rate of change in socioemotional problems between 15- and 35-months. Maternal depressive symptoms during pregnancy and postpartum were significantly correlated (r = 0.57, p < .001).
Parallel Mediation Model
Relationship status, maternal education, toddler sex, and COVID-19 impact were included as potential covariates on BITSEA intercept and slope, and maternal education and COVID-19 impact were included as a potential covariate on depressive symptoms. Significant covariates retained in the final latent growth parallel mediation model included education and COVID-19 impact on depressive symptoms during pregnancy (education: ß = −0.19, p < .001; COVID-19: ß = 0.38, p < .001) and 6-months postpartum (education: ß = −0.16, p < .05; COVID-19: ß = 0.35, p < .001). All other potential covariates were not significant once entered into the model and were removed from the final latent growth curve mediation model. Participant race, income, relationship status, and weeks gestation were included as auxiliary variables. The final conditional linear model provided a good fit to the data, χ2 (12) = 16.89, p = 0.15, RMSEA = 0.04, CFI = 0.99, SRMR = 0.03.
Results of Parallel Mediation Model Assessing the Direct and Indirect Effects From Maternal Adversity to Child Socioemotional Problems Intercept (Centered at 15 months) and Slope, Through Prenatal and Postpartum Depressive Symptoms
Note. ACEs = Adverse Childhood Experiences scale; CESD = Centre for Epidemiological Studies Depression scale; Postpartum CESD measured at 6 months postpartum; BITSEA = Brief Infant–Toddler Social and Emotional Assessment Problem Total Score. Bold values are significant based on 95% bootstrapped confidence intervals (CIs). Intercept represents average BITSEA problem scores at 15 months. Slope represents change in BITSEA problem scores from 15, 24, and 35 months.
In the above latent growth parallel mediation model the intercept of BITSEA problem total score was centered at 15-months. To determine whether maternal ACEs and depressive symptoms were related to socioemotional problems at 24- and 35-months, we conducted models that centered the intercept to represent average BITSEA total problem score at 24- and 35-months. Prenatal depressive symptoms were significantly associated with higher average BITSEA problems (intercepts) at 24- and 35-months, but did not predict changes in BITSEA over time (Supplemental Table S3 and S4). There were significant indirect effects between maternal ACEs and BITSEA intercepts centered at 24- and 35-months, through prenatal depressive symptoms. Indirect effects through postpartum depressive symptoms at 6-months were not significant (Supplemental Table S3 and S4).
Serial Mediation Model
The latent growth serial mediation model accounted for 17.5% of the variance in BITSEA intercept, 6% of the variance in BITSEA slope, and between 30%–38% of the variance in depressive symptoms (T1 R2 = .306; T2 R2 = .382). As shown in Figure 2 and Supplemental Table S5, maternal ACEs were associated with prenatal depressive symptoms, which in turn predicted the intercept of toddler behaviour problems. Prenatal depressive symptoms predicted postpartum depressive symptoms. Neither the serial indirect effect (Est = 0.03, CI [-0.01, 0.08]) or the indirect effect through postpartum depression (Est = 0.03, CI [-0.01, 0.14]) were significant. However, the indirect effect through prenatal depression was significant (Est = 0.14, CI [0.05, 0.30]).
Discussion
This prospective longitudinal study examined the association between maternal ACEs and emerging child socioemotional problems across the first three years of life, and whether prenatal or postpartum depressive symptoms mediated this association. The parallel mediation model results indicate that maternal ACEs were indirectly linked to average child behaviour at each time point (intercepts) through prenatal depressive symptoms, but not postpartum depressive symptoms. Although pregnancy depressive symptoms predicted postpartum depressive symptoms, we did not find evidence for a serial mediation, wherein pregnancy depression worked through postpartum depression to account for indirect effects from maternal ACEs to child socioemotional problems. To our knowledge, this is the first study to explore the potentially differential role of pregnancy and postpartum depressive symptoms in linking maternal childhood adversity to child socioemotional outcomes at multiple time points (15-, 24-, 35-months) in the first few years of life.
First, we found that, in the context of the COVID-19 pandemic, maternal ACEs were associated with higher prenatal and postpartum depressive symptoms as well as greater child socioemotional problems at ages 15-, 24- and 35 months-old. These results were shown based on bivariate correlations and direct effects in the mediation model. These findings are in line with prior research highlighting maternal ACEs as a risk factor for experiencing depression in the perinatal period (Racine et al., 2021) and for children experiencing socioemotional problems (Cooke et al., 2019; Plant et al., 2018; Racine et al., 2023). In addition, these findings extend this literature to indicate that, in this pandemic sample, maternal childhood adversity was not significantly related, directly or indirectly, to trajectories (slopes) of child socioemotional problems from 15- to 35-months postpartum. One conceptual interpretation of these findings is that maternal ACEs influence the earliest developmental processes that shape individual differences in socioemotional functioning, likely through prenatal factors; however, maternal ACEs do not appear to affect later processes that contribute to subsequent change and growth during the toddler period. It is also possible that in our sample of 1- to 3-year-olds, there was not sufficient variability in child behaviour problems to detect differences in trajectories based on maternal ACEs. One prior study demonstrated that maternal ACEs were indirectly associated with child socioemotional trajectories from 18-, 36-, to 60-months (Harris et al., 2023), suggesting that associations between maternal ACEs and trajectories of change in socioemotional problems are present later in childhood. Future research is needed to assess how maternal ACEs are associated with trajectories of child socioemotional problems across a longer period to determine if maternal ACEs relate to developmental variations of socioemotional problems through the life course.
In addition, our findings shed light on the associations between prenatal and postpartum depressive symptoms. Results of bivariate correlations and both mediation models indicate that maternal depressive symptoms in pregnancy and 6-months postpartum are significantly associated with each other, and with child socioemotional problems at all time points. These findings extend prior research showing that prenatal and postpartum mental health is associated with child socioemotional outcomes before (Phua et al., 2023; Rogers et al., 2020) and during (e.g., Duguay et al., 2022; López-Morales et al., 2023) the pandemic.
Once both prenatal and postpartum depressive symptoms were both incorporated in the parallel mediation model, only prenatal depressive symptoms, not depressive symptoms at 6-months postpartum, were directly linked to average child socioemotional problems at 15-, 24- or 35-months (intercepts). In addition to being correlated, the serial mediation demonstrates that prenatal depression predicts postpartum depressive symptoms, providing some support for a developmental cascade model. However, in the serial mediation model, only the indirect effect through prenatal depressive symptoms was significant (not the serial path, or the path through postpartum depression). Therefore, we did not find support for a temporal chain from maternal ACEs to child socioemotional outcomes, through linking paths of pregnancy and postpartum depressive symptoms. This nonsignificant association is possibly reflective of the timing of postpartum depressive symptoms at 6-months, that is, perhaps postpartum depressive symptoms measured earlier or later in the postpartum period might account for indirect associations between maternal ACEs and child outcomes. Future studies should investigate similar models, incorporating assessments of depressive symptoms both earlier and later in the postpartum period to explore this possibility further.
Interestingly, neither prenatal nor postpartum depressive symptoms were associated with change in toddler socioemotional problems. Although ample research examines how trajectories of perinatal depression are associated with child socioemotional outcomes at specific time points throughout development (e.g., Korja et al., 2024; Subbiah et al., 2024), less research examines associations between perinatal depression and trajectories of socioemotional development over the first few years of life (Morales et al., 2023). A study with older children showed that maternal depressive symptoms were linked to atypically elevated internalizing problems from ages 6–12 years (Ahun et al., 2018). Another study did not find significant associations between maternal depression at 2-months postpartum and trajectories of physical aggression from ages 3 to 6 years-old (Jambon et al., 2019). It is important for future research, with more diverse samples, to track how prenatal and postpartum depression might be associated with changes in socioemotional outcomes across the first three years of life, a critical period of child development.
As noted above, we explored the differential role of prenatal and postpartum depressive symptoms in linking maternal childhood adversity to child socioemotional outcomes. In both parallel and serial mediation models, although prenatal and postpartum depressive symptoms were associated, only prenatal depressive symptoms significantly mediated the link between maternal ACEs and child socioemotional outcomes at each time point. It is also possible that we observed a significant indirect effect of prenatal depressive symptoms because it was assessed concurrently with maternal ACEs. Measures assessed at the same time are typically more highly correlated. Importantly, in the parallel mediation model, we did not find a significant difference in the magnitude of indirect effects through prenatal or postpartum depressive symptoms. Thus, these results should not be interpreted to mean that prenatal depressive symptoms are more important in explaining the link between maternal ACEs and child socioemotional outcomes. Rather, given the strong connection between prenatal and postpartum depressive symptoms (as demonstrated by the serial mediation), we argue that depressive symptoms across the perinatal period should be seen as potential modifiable factors that can reduce the transmission of the effects of maternal ACEs on childhood mental health problems.
Practical Implications
The present findings suggest that, during the COVID-19 pandemic, maternal ACEs were associated with heightened risk for toddler socioemotional problems indirectly through maternal perinatal depressive symptoms. These findings are timely and support recent national guidelines and recommendations to prioritize early screening to detect and treat perinatal mental health problems in both the United States and Canada (Avalos et al., 2019; Vigod et al., 2025). These results are particularly concerning given the high prevalence of mental health problems among pregnant women and parents during and years after the pandemic (Caffieri et al., 2023; Khoury, Jambon, et al., 2023). A recent meta-analysis demonstrates that psychological interventions, particularly cognitive behavioural therapy and interpersonal psychotherapy, are effective in treating perinatal depression (Cuijpers et al., 2023; Pettman et al., 2023). Without intervention, the negative impacts on child development may persist. Notably, the perinatal period represents a critical window where maternal depression is potentially modifiable, offering an opportunity to mitigate socioemotional challenges in children.
Strengths, Limitations and Future Directions
This study has several strengths, including the longitudinal design, measurement of maternal depressive symptoms during pregnancy and the postpartum, and the examination of child socioemotional outcomes at specific time points as well as trajectories of socioemotional problems. Findings should be considered in light of study limitations. First, data was collected during the pandemic, when prenatal and postpartum depressive symptoms were higher than typically seen in the general population. As such, these findings might not generalize to pre-pandemic or post-pandemic times. Second, the sample consisted primarily of participants with relatively low sociodemographic risk (e.g., higher income and education levels), a limitation further compounded by the lower likelihood of study completion among participants with lower incomes or those not in a romantic relationship. This may limit the generalizability of findings to more advantaged individuals. Third, this study relied solely on self-report measures of maternal ACEs, maternal depressive symptoms and parent-reported assessments of toddler socioemotional functioning. Given that both measures of depression and toddler socioemotional problems were parent report, level of maternal depressive symptoms could impact ratings of toddler socioemotional problems. This reliance introduces the confound of shared method variance and potential response bias and recall bias in relation to maternal ACEs (Reuben et al., 2016). Related, maternal ACEs were measured in pregnancy, potentially contributing to stronger associations with prenatal, compared to postnatal, depressive symptoms. Future studies should aim to include participants with more diverse sociodemographic profiles, use different assessment techniques (such as interviews and self-reports), measure maternal ACEs prospectively, if possible, and involve multiple sources of information to enhance the applicability of these results. Fourth, although strong theory and past empirical findings informed the development of hypotheses, this correlational study does not allow for the determination of causal relationships between variables.
Conclusion
This study identifies maternal perinatal depressive symptoms, which are elevated during the COVID-19 pandemic, as a pathway through which higher maternal ACEs are associated with greater toddler socioemotional difficulties, during the first three years of life. This research demonstrates that the indirect link between maternal ACEs and child socioemotional problems is evident by one year of age, prior to when most young toddlers typically demonstrate emotional or behavioural problems. We found evidence for indirect effects on child socioemotional problems at 15-, 24-, and 35-months, through prenatal but not postpartum depressive symptoms. No associations were found in relation to trajectories of child socioemotional problems from 15- to 35 months. These findings highlight the impact of the COVID-19 pandemic on perinatal mental health and early childhood mental health, particularly for families who are affected by parent childhood adversity.
Supplemental Material
Supplemental Material - Adverse Childhood Experiences, Pregnancy and Postpartum Depressive Symptoms, and Child Socioemotional Problems Over the First Three Years of Life
Supplemental Material for Adverse Childhood Experiences, Pregnancy and Postpartum Depressive Symptoms, and Child Socioemotional Problems Over the First Three Years of Life by Jennifer E. Khoury, Marc Jambon, Mackenna Pattison, Andrea Gonzalez, Leslie Atkinson in Child Maltreatment
Footnotes
Acknowledgements
We’d like to thank the pregnant and postpartum women who participated in this research.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was funded by a Canadian Institute of Health Research (CIHR) Project Grant - PA: Pandemic and Health Emergencies Research (465280). This work was also supported by a Tier II Canadian Research Chair (CRC) in Interdisciplinary Studies in Neurosciences awarded to Dr. Jennifer Khoury and a Tier II CRC in Family Health and Preventive Interventions awarded to Dr. Andrea Gonzalez.
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Supplemental Material
Supplemental material for this article is available online.
Notes
References
Supplementary Material
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