Causal model of the association of social support during pregnancy with a perinatal and postpartum depressive state: A nationwide birth cohort - the Japan Environment and Children's Study

Inverse Association Between Mothers' Cognitive Social Capital During Pregnancy and Postpartum Depression: The Japan Environment and Children's Study

Purpose

Several studies have reported an apparent inverse association between cognitive social capital and depression in various groups, but insights into this association in perinatal mothers are fairly limited. Therefore, we explored the possible associations between expectant mothers' cognitive social capital (ie, neighborhood trust and reciprocity and generalized trust and reciprocity) and postpartum depression at 1 and 6 months after delivery.

Patients and Methods

As part of an ongoing cohort study, the Japan Environment and Children's Study, cognitive social capital was evaluated using a questionnaire survey during mid-late pregnancy and postpartum depression was assessed using the Japanese version of the Edinburgh Postnatal Depression Scale. This study analyzed data from 81,670 mothers. Logistic regression analysis was performed to calculate the odds ratios (ORs) for postpartum depression by the degree of neighborhood and generalized trust and reciprocity (high, relatively high, neutral, relatively low, and low) using the high category as a reference.

Results

Regardless of the measurement time point, prevalence gradually increased as the degree of neighborhood trust decreased (all p < 0.001), suggesting a higher likelihood of postpartum depression with less neighborhood trust. A comparable tendency was also observed for the other three variables of cognitive social capital (all p < 0.001). Moreover, the inverse association of postpartum depression with generalized trust and reciprocity was markedly stronger (ORs for low category ≥ 2.70) than that with neighborhood trust and reciprocity (ORs for low category ≤ 1.96).

Conclusion

Our findings highlight a statistically significant inverse association between cognitive social capital during pregnancy and postpartum depression at both time points.

Effectiveness of aerobic exercise in the prevention and treatment of postpartum depression: Meta-analysis and network meta-analysis

BACKGROUND

Aerobic exercise is widely recognized for improving mental health and reducing negative emotions, including anxiety. However, research on its role in preventing and treating postpartum depression (PPD) has yielded inconsistent results. Some studies show positive effects on PPD symptoms, while others find limited impact, suggesting various factors at play, such as exercise type, intensity, and individual differences. To address this gap, our study aims to comprehensively gather evidence on the preventive and therapeutic effects of aerobic exercise for PPD. We'll focus on differences in exercise program design and implementation, exploring how these factors impact intervention outcomes. By identifying effective exercise approaches, we aim to provide more comprehensive exercise prescription recommendations for this vulnerable population.

METHODS

We conducted a quantitative systematic review of the study in 5 representative databases for the effect of aerobic exercise on PPD. Meta-analysis and network meta-analysis were performed with Review-Manager.5.4 and Stata.16.0 software, respectively. This study has been registered on the official Prospero website, and the registration code is CRD42023398221.

RESULTS

Twenty-six studies with 2,867 participants were eventually included and the efficacy of aerobic exercise in preventing and treating postpartum depression is significant compared to standard care. (MD = -1.90; 95%CL: -2.58 to -1.21; I2 = 86%). Subgroup analysis suggests that the intervention objective (prevention vs. treatment) of exercise could potentially be a source of heterogeneity in this study, as the "Test for subgroup difference" revealed the presence of significant distinctions (p = 0.02<0.05). The "Test for subgroup difference" yielded non-significant results for both the supervised vs. unsupervised subgroup comparison (p = 0.55 > 0.05) and the individual vs. team subgroup comparison (p = 0.78 > 0.05). Nonetheless, when assessing their effect sizes [Subtotal (95%CL)], the supervised exercise group [-1.66 (-2.48, -0.85)] exhibited a slightly better performance than the unsupervised exercise group [-1.37 (-1.86, -0.88)], while the team exercise group [-1.43 (-1.94, -0.93)] slightly outperformed the individual exercise group [-1.28 (-2.23, -0.33)]. Network meta-analysis indicated that moderate intensity (35~45 min) group demonstrated a more pronounced intervention effect compared to low intensity (50~60 min) group [-2.63 (-4.05, -1.21)] and high intensity (20~30 min) group [-2.96 (-4.51, -1.41)], while the 3~4 times/week group had a more significant intervention effect compared to 1~2 times/week groups [-2.91 (-3.99, -1.83)] and 5~6 times/week groups [-3.28 (-4.75, -1.81)]. No significant differences were observed in pairwise comparisons of intervention effects among the five common types of aerobic exercises. (95%CL including 0). The Surface Under the Cumulative Ranking curve (SUCRA) results align with the findings mentioned above and will not be reiterated here.

CONCLUSION

The efficacy of aerobic exercise in preventing and treating postpartum depression is significant compared to standard care, with a greater emphasis on prevention. The optimal prescribed exercise volume for intervention comprises a frequency of 3~4 exercise sessions per week, moderate intensity (35~45 minutes). Currently, several uncharted internal factors influence the optimal intervention effect of aerobic exercise, such as the potential enhancement brought by team-based and supervised exercise. Given the absence of significant differences in certain results and the limitations of the study, it is essential to exercise caution when interpreting the outcomes. Further research is needed in the future to provide a more comprehensive understanding.

Relationship between prenatal checkup status and low birth weight: a nationwide birth cohort-the Japan Environment and Children's Study

PURPOSE

We investigated the association between prenatal checkup status and low birth weight (LBW). We also sought to identify the background factors of pregnant women that influence their attendance at prenatal checkups and consider measures that might prove useful in reducing the LBW rate.

METHODS

Using data from a large nationwide birth cohort study, the Japan Environment and Children's Study (JECS), the sample comprised 91,916 unique mother-infant pairs with singleton live births. The outcome variable was cases of LBW, and the exposure variable was prenatal checkup status (number of visits missed). Adjusted odds ratios (AORs) with 95% confidence intervals (CIs) were calculated by logistic regression analysis.

RESULTS

AORs (95% CIs) for cases of LBW were 1.57 (1.46-1.69) for 1 missed checkup, 2.40 (1.97-2.94) for 2 missed checkups, and 2.38 (1.46-3.88) for ≥3 missed checkups. A linear trend was also observed (P < .0001). Further analysis revealed that the main risk factors for missed checkups were divorced or widowed marital status, followed by negative attitude toward pregnancy, and single marital status, whereas protective factors were being employed and better mental health in mid-late pregnancy.

CONCLUSIONS

Our results suggest the importance of implementing various measures to promote regular attendance at prenatal checkups.

Longitudinal study of the relationship between number of prior miscarriages or stillbirths and changes in quality of life of pregnant women: the Japan Environment and Children's Study (JECS)

BACKGROUND

Although a history of miscarriage or stillbirth has been reported to negatively affect quality of life (QOL) during the subsequent pregnancy, the association between the number of previous miscarriages or stillbirths and QOL, as well as trends in QOL during pregnancy, has not been clarified. This study sought to determine this association during early and mid- to late pregnancy.

METHODS

Data from 82,013 pregnant women who participated in the Japan Environment and Children's Study (JECS) from January 2011 to March 2014 were analyzed. In early and mid/late pregnancy, participants completed questionnaires and QOL was assessed using the Physical and Mental Component Summary (PCS and MCS, respectively) scores from the 8-item Short-Form Health Survey (SF-8). The pregnant women were divided into four groups according to number of previous miscarriages or stillbirths (0, 1, 2, and ≥ 3), and the PCS and MCS scores in early pregnancy and mid/late pregnancy were compared between group 0 and groups 1, 2, and ≥ 3. Generalized linear mixed models were used for analysis.

RESULTS

PCS score in early pregnancy was lower in group 1 (β =  - 0.29, 95% confidence interval [CI] - 0.42 to - 0.15), group 2 (β =  - 0.45, 95% CI - 0.73 to - 0.18), and group ≥ 3 (β =  - 0.87, 95% CI - 1.39 to - 0.35) than in group 0. Group 1 and group ≥ 3 showed a trend for increased PCS score during pregnancy (β = 0.22, 95% CI 0.07 to 0.37 and β = 0.75, 95% CI 0.18 to 1.33, respectively) compared with group 0.

CONCLUSIONS

PCS score in early pregnancy was lower with a more frequent history of miscarriage or stillbirth. However, in terms of changes in QOL during pregnancy, pregnant women with a history of miscarriage or stillbirth showed greater increases in PCS score during mid/late pregnancy than pregnant women with no history of miscarriage or stillbirth.

Caesarean section and childhood obesity at age 3 years derived from the Japan Environment and Children's Study

Caesarean section (CS) birth is widely reported to be a risk factor for childhood obesity. Although susceptibility to childhood obesity is influenced by race and ethnicity, it is unclear whether this risk of childhood obesity with CS birth also applies in the Japanese population. We investigated the impact of CS birth on obesity at 3 years of age in Japanese children. We obtained data from 60,769 mother-toddler pairs in the Japan Environment and Children's Study, a large-scale birth cohort study. Obesity was determined by body mass index measured at 3 years of age. Analysis revealed that 11,241 toddlers (18.5%) had a CS birth and that 4912 toddlers (8.1%) were obese. The adjusted risk ratio for obesity at 3 years of age when born by CS compared with vaginal delivery, estimated using inverse probability of treatment weighting, was 1.16 (95% confidence interval 1.08-1.25). These results suggest that CS birth modestly increases the risk of obesity at 3 years of age in Japanese children.

Association of infants' feeding pattern up to 2 years postpartum with mothers' mental and physical health: the Japan Environment and Children's Study

BACKGROUND

Exclusive breastfeeding, a longer breastfeeding duration, and interaction with the baby during lactation improve mothers' mental health. However, few studies have targeted women around 2.5 years after childbirth, when women are still considered to have been in a period of mental and physical health vulnerability. This study examined this aspect in a large cohort of mother-child pairs.

METHODS

Data were obtained from 85,735 mothers in an ongoing nationwide birth cohort study in Japan. Exposures were exclusive breastfeeding (yes/no), continued breastfeeding up to 2 years (yes/no), and interaction with the baby during feeding (yes/no). Outcomes were mothers' mental and physical health 2.5 years after childbirth measured using Mental and Physical Component Summary scores (MCS and PCS scores, respectively) from the 8-item Short-Form Health Survey. Generalized additive mixed model analysis was used to derive each estimate for the three exposures and their interactions, with each "no" answer as reference.

RESULTS

Exclusive breastfeeding and interaction with the baby during feeding were associated with MCS score increases of 0.28 (95%CI: 0.10-0.47) and 0.41 (95%CI: 0.29-0.54), respectively. However, no associations were found for continued breastfeeding up to 2 years and no interactions were identified. No significant differences were observed for PCS scores.

LIMITATIONS

All variables were measured using a self-administered questionnaire.

CONCLUSIONS

Continued exclusive breastfeeding until 6 months and interaction with the baby during feeding may help to promote mother's mental health 2.5 years after childbirth. These findings further strengthen the rationale for the World Health Organization's recommended lactation practices.

Cesarean section and parenting stress: Results from the Japan Environment and Children's Study

BACKGROUND

Accumulating evidence suggests a long-term health risk of cesarean section for the mother and child, but few studies have examined the link between cesarean section and parenting stress. Here, we examined this association by exploiting a large dataset.

METHODS

Participants were 65,235 mothers participating in the Japan Environment and Children's Study, an ongoing nationwide birth cohort. Outcome variables were parenting stress assessed as total score and subscale scores (representing the difficult child, parental distress, and spouse factors) on the Japanese 19-item version of the Parenting Stress Index Short Form (J-PSI-SF). Exposures were the mode of delivery, the timing of the J-PSI-SF assessment (1.5, 2.5, and 3.5 years postpartum), and the interaction between them. Multivariate regression analysis was used to calculate adjusted β coefficients and standard error of the means (SEMs).

RESULTS

The J-PSI-SF total score was higher in the cesarean section group than in the vaginal delivery group (adjusted β = 0.24, SEM = 0.09). This increase was primarily due to higher scores for the difficult child factor (adjusted β = 0.18, SEM = 0.05) and not to higher scores for the parental distress or spouse factor.

CONCLUSIONS

Cesarean section was associated with higher parenting stress, especially in relation to the difficult child factor. Our results highlight the importance of paying particular attention to the mental health of both mother and child in the case of cesarean section.

Prediction model for nonopiate-induced neonatal abstinence syndrome

BACKGROUND

Neonatal abstinence syndrome (NAS) induced by opiate use is common worldwide. Psychiatric drugs are a more common cause of NAS in Japan but infants of mothers taking psychiatric medications do not always develop NAS. The purpose of this study was to develop a practical model for predicting the onset of nonopiate-induced NAS, using variables available at birth.

METHODS

In this diagnostic study, prediction models were developed using multivariable logistic regression with retrospective data collected at our hospital between 2010 and 2019. The NAS diagnosis was based on the Isobe score, and maternal medications were converted to dose equivalents.

RESULTS

A total of 164 maternal and infant dyads met the inclusion criteria; 91 were included in the analysis, of whom 29 infants (32%) were diagnosed with NAS. Final models were created with and without the drug indices. The model without the drug indices consisted of neonatal head circumference in z-scores and Apgar scores at 5 min < 9, and the model with the drug indices included these, as well as antipsychotics and hypnotics indices. The C-statistics were 0.747 (95% CI: 0.638-0.856), and 0.795 (95% CI: 0.683-0.907), respectively, indicating that the models possessed good predictive accuracy for NAS onset.

CONCLUSIONS

This study developed models that predicted nonopiate-induced NAS accurately. They may be further improved through the use of drug indices.

The Possible Effects of Zinc Supplementation on Postpartum Depression and Anemia

Background and Objectives: The effects of postpartum zinc supplementation are still unclear. Our purpose in this study is to investigate the association between Zn supplementation and postpartum depression, defined by an Edinburgh Postnatal Depression Scale (EPDS) score ≥ 9, and the effect on the hematological status of postpartum women. Materials and Methods: We first investigated whether zinc supplementation affected the perioperative levels of zinc, hemoglobin, and hematocrit in 197 cases who underwent cesarean section and had postpartum anemia. Next, logistic regression analyses were performed on 148 eligible cases to determine the association between zinc supplementation and postpartum depression. Results: Postpartum zinc supplementation significantly improved the status of maternal blood zinc levels and reduced the risk of developing postpartum depression (adjusted odds ratio: 0.249; 95% confidence interval: 0.062–0.988; p = 0.048). Iron supplementation is a standard and effective strategy for treating anemia; however, the combination of oral iron plus zinc supplementation resulted in slightly significant negative effects on postpartum hemoglobin and hematocrit compared to oral iron supplementation only. Conclusions: Postpartum zinc supplementation causes a significant positive effect on postpartum depression (EPDS score ≥ 9). Zinc supplementation had a negative but transient influence on the hematological status in women with postpartum anemia treated with oral iron supplementation; however, the differences were not clinically significant. Thus, we did not regard it as an adverse effect to be considered, and postpartum zinc supplementation may be viewed as beneficial in postpartum women.