Prepregnancy Obesity and a Biobehavioral Predictive Model for Postpartum Depression

Path analysis of influencing factors for anxiety and depression among first-trimester pregnant women

Background

Prenatal anxiety and depression exert a significant influence on the physiological and psychological health outcomes of both expectant mothers and their infants. The aim of this study was to explore the intrinsic relationships between maternal anxiety, depression in early pregnancy, and their influencing factors. The findings of this study provide scientific basis for developing targeted preventive interventions.

Methods

The study involved 887 expectant mothers in the early stages of pregnancy residing in Changsha City from March to August 2022. The sociodemographic characteristics, health and lifestyle factors, and pregnancy-related factors of participants were collected. The Edinburgh Postnatal Depression Scale and the Self-Rating Anxiety Scale were used to assess depression and anxiety, respectively. Chi-square tests and multivariate logistic regression models using SPSS 26.0 were used to assess factors impacting early pregnancy anxiety and depression. Amos 23.0 was used to construct a path model to determine the potential pathways of the influencing factors.

Results

In early pregnancy, the prevalence of depression and anxiety were 17.4% and 15.8%, respectively. Path analysis showed that early pregnancy anxiety and illness during pregnancy had a direct effect on early pregnancy depression. Anxiety had the greatest overall impact on early pregnancy depression. Education, maternal comorbidities, symptoms of pregnancy, electronic device usage time, work stress, active smoking in the 6 months before pregnancy, and sleep quality were found to solely exert indirect effects on early pregnancy depression. Sleep quality had the greatest overall impact on early pregnancy anxiety. Active smoking in the 6 months before pregnancy, sleep quality, and work stress only had a direct impact on early pregnancy anxiety. Additionally, electronic device usage duration and monthly per capita household income exclusively indirectly impacted symptoms of early pregnancy anxiety.

Conclusion

The study highlights the importance of targeted interventions in early screening. Avoiding excessive use of electronic devices and active smoking in the 6 months before pregnancy, alleviating work stress and symptoms of pregnancy, increasing education levels and monthly per capita household income, improving sleep quality, and actively preventing illnesses during pregnancy and maternal comorbidities might reduce anxiety and depression in early pregnancy.

Risk Factors of Postpartum Depression

Postpartum depression (PPD) is a widespread mental health problem and one of the prime causes of maternal suffering and ill health. On a global level, the prevalence of the disorder is about 10 to 15%. Symptoms generally appear within the first four to six weeks, which is the high-risk period. However, it may develop up to one year post-delivery. PPD presents with symptoms of classical depression, including mood fluctuations, bouts of crying, lack of interest in the child, and even thoughts of suicide. PPD not only has adverse effects on the mother's health but also hampers the growth and development of the child. It hampers the formation of a healthy mother-child bond, which in turn may impact feeding practices. The social environment of the infant during the first few months is primarily provided by the mother, and PPD may thus impact the child's development. It also increases the child's susceptibility to malnutrition. Research on postpartum depression has garnered momentum within the last few years. However, the masses are still largely unaware of the disorder and its implications. There is also an inadequacy of awareness of the risk factors of PPD. The cross-cultural differences in manifestations and appropriate preventive measures have not been extensively studied. Some risk factors for PPD are similar to those for classic depression; however, obstetrical and pediatric factors are also involved. This literature review aims to assess the currently known risk factors for PPD, their strength of association, and probable mechanisms to help identify the high-risk group and enable the implementation of preventive measures or facilitate early diagnosis. The factors identified spanned sociodemographic, biological, psychological, and obstetric domains. These included socioeconomic standing, marital relationship, history of psychiatric illness, social support, gestational diabetes, vitamin D deficiency, immigration status, delivery method, violence and abuse, birth experience, and biological and epigenetic markers. The risk factors for postpartum depression are numerous and may have strong to weak associations with the development of PPD. A previous history of depression or psychiatric illness, depressive symptoms during pregnancy, gestational diabetes, and a lack of spousal and social support were the most powerful risk factors. Other significant factors include complications during pregnancy, low socioeconomic status, and stressful life events. Studies on maternal age and chronic illness as risk factors were inconclusive. The roles of genetic and epigenetic markers, cultural factors, and vitamin D insufficiency require further investigation.

Association between visceral adipose tissue and major depressive disorder across the lifespan: A scoping review

OBJECTIVES

Increasing evidence supports a bidirectional relationship between major depressive disorder (MDD) and obesity, but the role of visceral adipose tissue (VAT) as a measure of obesity in relation to MDD is not well understood. Here we review literature investigating the link between MDD and VAT in terms of biomarkers, sex differences, and aging.

METHODS

PubMed, EMBASE, PsycINFO, and CINAHL searches were conducted on December 11, 2020. No date or language limits were imposed. Major concepts searched were Depressive Disorder linked with Adipose Tissue, White, Hypothalmo-Hypophyseal System, and Pituitary-Adrenal System in addition to keywords. A final set of 32 items meeting criteria for inclusion.

RESULTS

Converging biological evidence suggests a significant bidirectional relationship between VAT and MDD across the lifespan. In adulthood, greater VAT was associated with increased risk for depression, especially in vulnerable groups such as individuals who are overweight/obese, postmenopausal women, and individuals with comorbid medical or psychiatric illness. In older adults, sarcopenia had an impact on the relationship between abnormal VAT and risk of depression. Additionally, sex differences emerged as a potential factor affecting the strength of the association between VAT and depression.

CONCLUSIONS

Elucidating the pathophysiological mechanisms associated with increased rates of depression in obese individuals will be crucial for developing specific treatment strategies that seek to improve outcomes in individuals with comorbid depression and obesity. Moreover, identifying age- and sex-specific risk factors may contribute to a more personalized medicine approach, thereby improving the quality of clinical care.

The impact of obesity-related neuroinflammation on postpartum depression: A narrative review

Obesity is currently one of the most serious health problems, affecting 13% of the world's adult population. Obesity is characterized by persistent low-grade chronic inflammation that assumes systemic proportions and triggers several associated metabolic diseases. Furthermore, obesity has been associated with an increased occurrence of central disorders such as impaired cognitive function, reward system dysfunction, and depression. In summary, there is a quantitative reduction in the release of neurotransmitters in depression. Postsynaptic cells capture lower concentrations of neurotransmitters, which leads to a functional reduction in the central nervous system (CNS). Globally, approximately 15-65% of women experience depressive symptoms during pregnancy, depending on their location. Depressive symptoms persist in some women, leading to postpartum depression (PPD). Thus, obesity may be considered a risk factor for PPD development. This study aimed to synthesize studies on the impact of obesity-related neuroinflammation and PPD. We conducted a narrative review of the relevant literature. The search was performed in electronic databases, specifically PubMed, selecting articles in English published from 2014 to 2021 using the narrative review methodology.

Predicting perinatal health outcomes using smartphone-based digital phenotyping and machine learning in a prospective Swedish cohort (Mom2B): study protocol

INTRODUCTION

Perinatal complications, such as perinatal depression and preterm birth, are major causes of morbidity and mortality for the mother and the child. Prediction of high risk can allow for early delivery of existing interventions for prevention. This ongoing study aims to use digital phenotyping data from the Mom2B smartphone application to develop models to predict women at high risk for mental and somatic complications.

METHODS AND ANALYSIS

All Swedish-speaking women over 18 years, who are either pregnant or within 3 months postpartum are eligible to participate by downloading the Mom2B smartphone app. We aim to recruit at least 5000 participants with completed outcome measures. Throughout the pregnancy and within the first year postpartum, both active and passive data are collected via the app in an effort to establish a participant's digital phenotype. Active data collection consists of surveys related to participant background information, mental and physical health, lifestyle, and social circumstances, as well as voice recordings. Participants' general smartphone activity, geographical movement patterns, social media activity and cognitive patterns can be estimated through passive data collection from smartphone sensors and activity logs. The outcomes will be measured using surveys, such as the Edinburgh Postnatal Depression Scale, and through linkage to national registers, from where information on registered clinical diagnoses and received care, including prescribed medication, can be obtained. Advanced machine learning and deep learning techniques will be applied to these multimodal data in order to develop accurate algorithms for the prediction of perinatal depression and preterm birth. In this way, earlier intervention may be possible.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Swedish Ethical Review Authority (dnr: 2019/01170, with amendments), and the project fully fulfils the General Data Protection Regulation (GDPR) requirements. All participants provide consent to participate and can withdraw their participation at any time. Results from this project will be disseminated in international peer-reviewed journals and presented in relevant conferences.

Postpartum Diet and the Lifestyle of Korean and Chinese Women: A Comparative Study

Objective

The study investigated and compared postpartum diet and behaviors, nutrition education, and psychological health status among Korean and Chinese postpartum women (0-6 months after delivery).

Methods

A total of 221 Korean mothers in Gyeonggi-do (South Korea) and 221 mothers in Jinhua (China) participated in the survey between November and December 2018, and the results were statistically analyzed using the SPSS Statistics 25.0 software.

Results

Many postpartum behaviors, such as postpartum diet pattern and care duration differed between Korean and Chinese mothers. The former showed a stronger desire for nutrition education compared with the latter (p < 0.001). Korean mothers' life and meal satisfaction, and contentment with their husband's support were all ~0.5 points higher compared with Chinese mothers, particularly regarding spousal support (p < 0.001). Postpartum depression stresses positively correlated with postpartum infant care stress and negatively correlated with life satisfaction. In addition, primipara mothers were more in need of infant care support and guidance concerning appropriate baby-feeding techniques compared with multipara mothers.

Conclusion

Traditional culture was a crucial factor that influenced the perceptions of postpartum women in South Korea and China. Culturally tailored nutrition education and exercise programs may benefit Korean and Chinese women after childbirth.

The Association between Weight-related Variables and Postpartum Depressive Symptoms

Objectives: Postpartum depressive symptoms (PPDS) are common, and weight-related variables may be risk factors. In this study, we examined associations between weight-related variables and PPDS in postpartum women. Methods: Participants who gave birth within the past 12 months completed an online survey assessing various weight-related variables and PPDS. We examined associations between weight-related variables and PPDS using regression models. Results: Participants (N=315) were 30.1±3.9 years of age and 5.6±3.7 months postpartum. A majority were white (96.2%), married (87.9%), and had a bachelor's degree or higher (70.5%). Having a higher pre-pregnancy body mass index (BMI) and current BMI, lower weight loss at 6 months postpartum, and substantial postpartum weight retention were associated with higher PPDS. There was no relationship between total gestational weight gain, IOM weight gain category, excess weight gain, postpartum weight retention, and pre-pregnancy-to-postpartum change in BMI, and postpartum depressive symptoms. Conclusions: Understanding factors associated with postpartum depressive symptoms can help to develop and implement appropriate screenings/follow-ups and interventions among those at greatest risk. Given the potential connection to PPDS, there is a need for interventions aimed at promoting healthy pre-conception weight and helping women to lose excess pregnancy weight during the postpartum period.

Postpartum depression symptoms in survey-based research: a structural equation analysis

BACKGROUND

Since the last decade, postpartum depression (PPD) has been recognized as a significant public health problem, and several factors have been linked to PPD. Mothers at risk are rarely undetected and underdiagnosed. Our study aims to determine the factors leading to symptoms of depression using Structural Equation Modeling (SEM) analysis. In this research, we introduced a new framework for postpartum depression modeling for women.

METHODS

We structured the model of this research to take into consideration the Malaysian culture in particular. A total of 387 postpartum women have completed the questionnaire. The symptoms of postpartum depression were examined using the Edinburgh Postnatal Depression Scale (EPDS), and they act as a dependent variable in this research model.

RESULTS

Four hundred fifty mothers were invited to participate in this research. 86% of the total distributed questionnaire received feedback. The majority of 79.6% of respondents were having depression symptoms. The highest coefficients of factor loading analysis obtained in every latent variable indicator were income (β = 0.77), screen time (β = 0.83), chips (β = 0.85), and anxiety (β = 0.88). Lifestyle, unhealthy food, and BMI variables were directly affected by the dependent variable. Based on the output, respondents with a high level of depression symptoms tended to consume more unhealthy food and had a high level of body mass indexes (BMI). The highest significant impact on depression level among postpartum women was unhealthy food consumption. Based on our model, the findings indicated that 76% of the variances stemmed from a variety of factors: socio-demographics, lifestyle, healthy food, unhealthy food, and BMI. The strength of the exogenous and endogenous variables in this research framework is strong.

CONCLUSION

The prevalence of postpartum women with depression symptoms in this study is considerably high. It is, therefore, imperative that postpartum women seek medical help to prevent postpartum depressive symptoms from worsening.

Pregestational overweight and obesity and symptoms of postpartum depression: Data from the Birth in Brazil Study

BACKGROUND

Relationship between pregestational overweight and obesity and symptoms of postpartum depression (PPD) has been documented in developed countries. In middle and low-income countries the studies are scarce and the pattern of findings is more mixed. Our objective is to assess the effect of pregestational overweight and obesity on development symptoms of PPD in a nationwide Brazilian study.

METHODS

The study included 23,894 puerperal women, from 2011 to 2012. The Edinburgh Postnatal Depression Scale (EPDS) was applied from 6 to 18 months postpartum, with ≥13 points as the cutoff. Classification of pregestational nutritional status followed the method recommended by the Institute of Medicine. Confounding variables were identified using directed acyclic graph (DAG), and propensity score estimated the effect of nutritional status on PPD symptoms.

RESULTS

Prevalence of PPD was 26.3%. Women with excess weight represented nearly 32% of the sample. In the crude analysis, women with pregestational obesity showed 23% higher odds of developing symptoms of PPD when compared to those with normal weight (OR=1.23 CI 95% 1.04-1.45). There was a loss of statistical significance after propensity score analysis (OR=1.14 CI 95% 0.91-1.42).

LIMITATIONS

The symptoms of PPD were measured in a single moment, and sensitivity analysis revealed the existence of omitted or non-measured variables potentially modifying these estimates.

CONCLUSIONS

Although we did not find a relationship between pregestational nutritional status and depressive symptoms, the results are important because of the problem's magnitude. Future studies should aim at a more comprehensive understanding of the complex relationship between the variables.

Risk factors for postpartum depression: An evidence-based systematic review of systematic reviews and meta-analyses

PURPOSE

Postpartum depression (PPD) is the most common psychiatric condition after childbirth which not only effects the mother's health, but also might have impact on child's development and parenting behaviors. Because the etiology of PPD has not been fully cleared, the efforts towards identification of risk factors are crucial for both the children and mother's health.

METHOD

PubMed, EMBASE and PsycINFO databases were searched since inception until July 2019 to collect data about the risk factors of PPD and only systematic review and meta-analysis can be included.

RESULT

To identify the real risk factors, protective factors and controversial factors, nineteen parts of the interpretation were adopted. The risk factors are mainly concentrated in the following aspects: violence and abuse, immigration status, gestational diabetes, cesarean section, depressive history, vitamin D deficiency, obese and overweight, postpartum sleep disruption and poor postpartum sleep, lack of social support, traditional dietary pattern (Japanese, Indian, United Kingdom, and Brazilian dietary pattern), multiple births, preterm and low-birth-weight infants, postpartum anemia, negative birth experience. The controversial factors are serum level of cortisol, thyroid peroxidase autoantibodies status, acculturation, traditional confinement practices. Skin-to-skin care, higher concentrations of DHA in mothers' milk, greater seafood consumption, healthy dietary patterns, multivitamin supplementation, fish and PUFA intake, calcium, Vitamin D, zinc and possibly selenium are protective factors.

CONCLUSION

Thirteen risk factors were identified, but five factors still controversial due to the insufficient of the evidence. What's more, skin-to-skin care and some nutrition related factors are protective factors against PPD.

Perinatal Predictors of Postpartum Depression: Results of a Retrospective Comparative Study

Postpartum mood disorders occur in a considerable number of women with the most common postpartum disorder being baby blues. The study aimed at the identification of the risk factors present before delivery, which may be comprised in prophylactic programs concerning postpartum mood disorders. The research material includes data retrieved from the medical record of patients delivering in Warsaw in the years 2010–2017 who routinely completed Edinburgh Postnatal Depression Scale (EPDS) after delivery. Data of 604 patients were analyzed. The study group included 75 women who obtained at least 12 points in EPDS, which constituted 12.4% of the whole group (mean = 14.92, SD = 3.05). The control group was made up of 75 women who obtained no more than 5 points in EPDS. A significant correlation was reported between the parity and their order vs. the risk of developing postpartum mood disorders. Women with an increased risk delivered at about 37 gestational weeks, while women in whom the risk of such disorders was low delivered at about 39 gestational weeks. No increased risk was noted in women with premature rupture of membranes. Primigravidas and women who delivered prematurely were the most predisposed to developing postpartum depression and should undergo screening tests in the perinatal period.

History of premenstrual syndrome and development of postpartum depression: A systematic review and meta-analysis

BACKGROUND

Premenstrual syndrome (PMS) is thought to be a risk factor for postpartum depression (PPD), but results from studies examining the association have been mixed.

OBJECTIVES

To estimate the association between pre-pregnancy history of PMS and development of PPD and evaluate the risk of bias of included evidence.

SEARCH STRATEGY

PubMed, EMBASE, CINAHL, PsycINFO, Cochrane Library, CNKI, Wanfang Data, and reference lists of relevant papers were searched.

SELECTION CRITERIA

Observational studies that collected pre-pregnancy history of PMS and measured PPD status between one week and one year after delivery were included.

DATA COLLECTION AND ANALYSIS

This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Random-effect models were used to calculate pooled odds ratios (ORs) with 95% confidence interval (CI). Small study effect was analysed by funnel plot. Risk of bias was assessed using the Risk of Bias Instrument for Non-Randomized Studies of Exposures (ROBINS-E).

MAIN RESULTS

Our meta-analysis included 19 studies. Overall, women with a pre-pregnancy history of PMS had more than double the odds of PPD compared to those without PMS (OR: 2.20, 95% CI: 1.81-2.68). However, the quality of evidence was low: five studies had moderate risk, eleven studies had serious risk, and three studies had critical risk of bias.

CONCLUSIONS

Current evidence supports a significant association between history of PMS and development of PPD. Well-designed prospective studies are needed to further investigate this relationship.

The association between body mass index and postpartum depression: A population-based study

BACKGROUND

Postpartum depression (PPD) reportedly affects between 6.5-19% of all new mothers. Identifying those at greatest risk for PPD has implications for prevention, early detection and intervention. While the relationship between extremes of body mass index (BMI) and depression has been frequently studied, the association between BMI and PPD is less understood.

METHODS

Prospective cohort of all women with live singleton births in Sweden 1997-2008. We calculated the relative risk (RR) for PPD in relation to each woman's BMI and depression history. PPD diagnosis was based on a clinical diagnosis of depression within the first postpartum year.

RESULTS

First trimester BMI measurements were available for 611,506 women. Low BMI (< 18.5) RR_adj = 1.52, [95% CI: 1.30-1.78] and high BMI (> 35) RR_adj = 1.23, [95% CI: 1.04-1.45] were associated with increased PPD risk. Women with a depression history had an increased risk with low BMI (RR_adj = 1.51, [95% CI: 1.17-1.95]).

LIMITATIONS

Only first births were analyzed, potentially underestimating PPD incidence. Clinical data from health registries offers limited resolution regarding the specificity of diagnoses and incomplete sensitivity if women do not seek care.

CONCLUSIONS

First trimester of pregnancy BMI is associated with PPD risk. This risk is further modified by depression history. While low BMI places all women at risk for PPD, being overweight increases risk of PPD only in women without a history of depression. Future research should explore potentially modifiable mechanisms involved in the relationship between PPD and BMI and should also examine interventional strategies for pregnant women at the extremes of BMI and/or with a depression history.

Maternal early pregnancy obesity and depressive symptoms during and after pregnancy

BACKGROUND

Previous studies have linked maternal obesity with depressive symptoms during and after pregnancy. It remains unknown whether obesity associates with consistently elevated depressive symptoms throughout pregnancy, predicts symptoms postpartum when accounting for antenatal symptoms, and if co-morbid hypertensive and diabetic disorders add to these associations. We addressed these questions in a sample of Finnish women whom we followed during and after pregnancy.

METHODS

Early pregnancy body mass index, derived from the Finnish Medical Birth Register and hospital records in 3234 PREDO study participants, was categorized into underweight (<18.5 kg/m2), normal weight (18.5-24.99 kg/m2), overweight (25-29.99 kg/m2), and obese (⩾30 kg/m2) groups. The women completed the Center for Epidemiological Studies Depression Scale biweekly during pregnancy, and at 2.4 (s.d. = 1.2) and/or 28.2 (s.d. = 4.2) weeks after pregnancy.

RESULTS

In comparison to normal weight women, overweight, and obese women reported higher levels of depressive symptoms and had higher odds of clinically significant depressive symptoms during (23% and 43%, respectively) and after pregnancy (22% and 36%, respectively). Underweight women had 68% higher odds of clinically significant depressive symptoms after pregnancy. Overweight and obesity also predicted higher depressive symptoms after pregnancy in women not reporting clinically relevant symptomatology during pregnancy. Hypertensive and diabetic disorders did not explain or add to these associations.

CONCLUSIONS

Maternal early pregnancy overweight and obesity and depressive symptoms during and after pregnancy are associated. Mental health promotion should be included as an integral part of lifestyle interventions in early pregnancy obesity and extended to benefit also overweight and underweight women.

Use of the Antenatal Risk Questionnaire to Assess Psychosocial Risk Factors Associated with Risk for Postpartum Depression: A Pilot Study

INTRODUCTION

Postpartum depression is the most common complication of childbirth. The purpose of this pilot study was to examine use of the Antenatal Risk Questionnaire (ANRQ) to assess psychosocial risk factors associated with increased risk for the development of symptoms of postpartum depression.

METHODS

This study was a prospective investigation of women during the third trimester of pregnancy. Women were recruited from a high-volume collaborative obstetric and midwifery practice in a large academic tertiary-care hospital. Participants were enrolled during their third trimesters of pregnancy and studied through 6 weeks postpartum. Surveys were completed for psychosocial risk (ANRQ), perceived stress, and symptoms of depression. Bivariate analysis was conducted and multiple regression analysis was performed to examine the effects of the predictor variables on the outcome variable, symptoms of depression at 6 weeks postpartum.

RESULTS

Thirty-five women participated in the study. Prenatal ANRQ scores, Perceived Stress Scale (PSS) scores, and Edinburgh Postnatal Depression Scale (EPDS) scores were significantly correlated with EPDS scores at 6 weeks postpartum. In the multiple regression analysis, the prenatal ANRQ score was a significant predictor of the postpartum EPDS score, whereas the prenatal PSS and EPDS scores were not significant. This regression model explained 57% of the variance in symptoms of depression at 6 weeks postpartum.

DISCUSSION

Key past and present psychosocial risk factors experienced by women (measured by the prenatal ANRQ) were a significant predictor of postpartum depressive symptoms. In light of our results, use of the ANRQ in clinical practice warrants further exploration.

Risk factors for postpartum depression among Chinese women: path model analysis

Background

Postpartum depression causes harm to both mothers and infants. The purpose of this study was to find out several potential risk factors, and to identify the intrinsic interrelationships between factors and postpartum depression by constructing a path model. The results of this study may help to control the increasing incidence of maternal postpartum depression.

Methods

The study was based on a sample of mothers from a cross-sectional study which was set up at 4 weeks after a mother had childbirth and was conducted in three streets at Kaifu District of Changsha in Hunan province from January to December 2015. Questionnaires were distributed to subjects who responded to questions concerning factors related to pregnancy, delivery and infants within 4 weeks after childbirth. The Edinburgh Postnatal Depression Scale (EPDS) was used to measure postpartum depression. Chi-square test was used to detect significant differences between non-postpartum depression group and postpartum depression group. A path model was constructed to explore the interrelationships between variables, and to verify the relationships between variables and postpartum depression.

Results

The proportion of maternal postpartum depression was 6.7%. Univariate analysis showed that there were significant differences between non-postpartum depression group and postpartum depression group (all P-values <0.05) on the part of maternal age, parity, frequent exposure to mobile phone during pregnancy, gestational hypertensive disorders, fetus number, premature delivery, birth weight, initiation of breastfeeding, mode of feeding, infant illness within 4 weeks after delivery and infant weight at 4 weeks. Path analysis results showed that the final model could be fitted well with sample data (P = 0.687, CMIN/DF = 0.824, NFI = 0.992, RFI = 0.982, IFI = 1.002, TLI =1.004, CFI = 1.000 and RMSEA < 0.001). Frequent exposure to mobile phone during pregnancy, maternal age and gestational hypertensive disorders had both direct and indirect effects on postpartum depression. Mode of feeding and infant weight at 4 weeks, which was the most total effect on postpartum depression, had only a direct impact on postpartum depression. Fetus number, premature delivery, initiation of breastfeeding and birth weight had only an indirect influence on postpartum depression.

Conclusion

The findings of this study suggest that constructing a path analysis model could identify potential factors and explore the potential interrelations between factors and postpartum depression. It is an effective way to prevent maternal postpartum depression by taking appropriate intervention measures and carrying out health education for pregnant women.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-017-1320-x) contains supplementary material, which is available to authorized users.