Preschool Behavioral Problems: Links with Maternal Oxytocin and Caregiving Sensitivity in the Postnatal Period, and Concurrent Maternal Psychopathology and Attachment State-of-Mind.

This study investigated maternal oxytocin, caregiving sensitivity and mother-to-infant bonding at 3-months postpartum as predictors of child behavior and psychological outcomes in the preschool years, when controlling for concurrent maternal negative emotional symptoms and adult attachment state-of-mind. Forty-five mother-child dyads were assessed at 3-months and 3.5 years postpartum using mix of questionnaires, observational, interview and biological methods. Results showed that lower levels of maternal baseline oxytocin at 3-months postpartum significantly predicted emotional reactivity in the child at 3.5 years. When maternal adult attachment state-of-mind and negative emotional symptoms were included, lower levels of maternal baseline oxytocin at 3-months postpartum significantly predicted withdrawn child behavior. In addition, unresolved adult attachment and maternal negative emotional symptoms were significantly associated child behavioral disturbance in a range of areas. Findings highlight maternal postnatal oxytocin as a potential indicator of children who may be more likely to show emotional reactivity and withdrawn behavior in the preschool years.

Antenatal depression screening and psychosocial assessment in an Australian private hospital: An evaluation.

BACKGROUND: Universal mental health screening and psychosocial assessment during pregnancy have been recommended as best practice, but uptake of universal programs in the private hospital system has been slow. AIM: The aim of this study was to evaluate the Pre-admission Midwife Appointment Program (PMAP), an antenatal mental health screening program at the Mater Hospital, Sydney. MATERIALS AND METHODS: In this mixed-methods design study, PMAP interview data were collected for a consecutive series of 485 women who attended the PMAP during a 10-month period. Women also completed two postnatal telephone interviews (10 weeks and 9 months postpartum). The interviews involved depression screening and questions about the program. RESULTS: Of the 485 participants, 4.1% screened positive for depression on the Edinburgh Postnatal Depression Scale. In total, 19% were identified as currently suffering from, or at risk of developing, perinatal mental health issues; referrals to support services were provided for the 13% who were not already linked in with appropriate supports. All women displayed a decrease in depressive symptom severity from pregnancy to 10 weeks and 9 months postpartum. The PMAP was viewed positively by consumers, with >93% viewing the program as helpful and >98% saying that they would recommend the program to others. Additional program benefits identified included opportunities to gain practical information and prepare for motherhood and to think/reflect on their emotional well-being. CONCLUSIONS: Given the observed rates of psychosocial risk among this sample, related referral opportunities and positive consumer feedback, we recommend other Australian private hospitals consider implementing PMAP or similar programs.

The impact of midwifery continuity of care on maternal mental health: A narrative systematic review.

BACKGROUND: Systematic reviews have shown that midwifery continuity of care programs lead to improvements in birth outcomes for women and babies, but no reviews have focused specifically on the impact of midwifery continuity of care on maternal mental health outcomes. OBJECTIVE: To systematically review the available evidence on the impact of midwifery continuity of care on maternal mental health during the perinatal period. METHOD: A systematic search of published literature available through to March 2021 was conducted. A narrative approach was used to examine and synthesise the literature. RESULTS: The search yielded eight articles that were grouped based on the mental health conditions they examined: fear of birth, anxiety, and depression. Findings indicate that midwifery continuity of care leads to improvements in maternal anxiety/worry and depression during the perinatal period. CONCLUSION: There is preliminary evidence showing that midwifery continuity of care is beneficial in reducing anxiety/worry and depression in pregnant women during the antenatal period. As the evidence stands, midwifery continuity of care may be a preventative intervention to reduce maternal anxiety/worry and depression during the perinatal period.

The contributions of maternal oxytocin and maternal sensitivity to infant attachment security.

This study investigated links between maternal postnatal oxytocin, maternal sensitivity, and infant attachment security. At 3-months postpartum, participants (n=88) took part in a structured parent-infant interaction. Maternal oxytocin levels were assessed via blood, before and after the interaction. At 12-months postpartum, mother-child dyads completed the Strange Situation Procedure. Neither baseline oxytocin, oxytocin response, or maternal sensitivity were identified as significant independent predictors of infant attachment security or organisation. However, an interaction effect was identified, with higher maternal sensitivity being associated with secure infant attachment for mothers who showed an increase in oxytocin during parent-child interaction. Results indicate that maternal sensitivity, when accompanied by an increase in maternal oxytocin during parent-child interaction, is associated with the establishment of a positive early parent-child attachment relationship. This adds to the growing body of evidence highlighting maternal oxytocin response as a key adaptive process in the postpartum period.

Health professional perspectives on an antenatal mental health screening program in a private hospital.

BACKGROUND: Perinatal mental ill-health is a global health priority. Mental health screening during pregnancy is a routine part of clinical practice in many public hospital obstetric services across Australia, but implementation in the private hospital system has lagged. AIMS: This study explored health professionals' perspectives on the Pre-admission Midwife Appointment Program (PMAP), an antenatal mental health screening program at the Mater Hospital, Sydney. MATERIALS AND METHODS: Nine midwives and three medical specialists participated in focus groups or individual interviews; key themes were determined using thematic qualitative analysis. RESULTS: Five major themes and three sub-themes were identified: immediate benefits to women (identifying women at risk; referrals to support services; supporting and educating women); enhanced overall quality of care at the hospital; the dilemma of partners attending; factors that make the program successful; and recommendations for improvement. CONCLUSIONS: Results will inform the implementation of antenatal mental health screening programs at other private hospitals across Australia.

Psychosocial and obstetric determinants of women signalling distress during Edinburgh Postnatal Depression Scale (EPDS) screening in Sydney, Australia.

BACKGROUND AND OBJECTIVES: The perinatal period presents a high-risk time for development of mood disorders. Australia-wide universal perinatal care, including depression screening, make this stage amenable to population-level preventative approaches. In a large cohort of women receiving public perinatal care in Sydney, Australia, we examined: (1) the psychosocial and obstetric determinants of women who signal distress on EPDS screening (scoring 10-12) compared with women with probable depression (scoring 13 or more on EPDS screening); and (2) the predictive ability of identifying women experiencing distress during pregnancy in classifying women at higher risk of probable postnatal depression. METHODS: We analysed routinely collected perinatal data from all live-births within public health facilities from two health districts in Sydney, Australia (N = 53,032). Perinatal distress was measured using the EPDS (scores of 10-12) and probable perinatal depression was measured using the EPDS (scores of 13 or more). Logistic regression models that adjusted for confounding variables were used to investigate a range of psychosocial and obstetric determinants and perinatal distress and depression. RESULTS: Eight percent of this cohort experienced antenatal distress and about 5 % experienced postnatal distress. Approximately 6 % experienced probable antenatal depression and 3 % experienced probable postnatal depression. Being from a culturally and linguistically diverse background (AOR = 2.0, 95% CI 1.8-2.3, P < 0.001), a lack of partner support (AOR = 2.9, 95% CI 2.3-3.7) and a maternal history of childhood abuse (AOR = 1.9, 95% CI 1.6-2.3) were associated with antenatal distress. These associations were similar in women with probable antenatal depression. Women who scored 10 to12 on antenatal EPDS assessment had a 4.5 times higher odds (95% CI 3.4-5.9, P < 0.001) of experiencing probable postnatal depression compared with women scoring 9 or less. CONCLUSION: Antenatal distress is more common than antenatal depressive symptoms and postnatal distress or depression. Antenatal maternal distress was associated with probable postnatal depression. Scale properties of the EPDS allows risk-stratification of women in the antenatal period, and earlier intervention with preventively focused programs. Prevention of postnatal depression could address a growing burden of illness and long-term complications for mothers and their infants.

Determinants of antenatal depression and postnatal depression in Australia.

BACKGROUND: Depression is a leading source of morbidity and health loss in Australian women. This study investigates the determinants of antenatal depressive symptoms and postnatal depressive symptoms in an Australian population, including people from culturally and linguistically diverse (CALD) backgrounds. METHOD: The study used a retrospective cohort of mothers of all live births in public health facilities in 2014 (N = 17,564) within South Western Sydney Local Health District and Sydney Local Health District in New South Wales, Australia. Prevalence of antenatal and postnatal depressive symptoms were estimated for the cohort. Multivariate logistic regression models were conducted to investigate the sociodemographic, psychological and health service determinants of antenatal and postnatal depressive symptoms, measured using the Edinburgh Postnatal Depression Scale (EPDS). RESULTS: The prevalence of antenatal and postnatal depressive symptoms was 6.2% and 3.3% of the cohort, respectively. Significant risk factors for maternal depressive symptoms during pregnancy were, a lack of partner support, history of intimate partner violence, being from the CALD population and low socioeconomic status. Self-reported antenatal depressive symptoms were strongly associated with postnatal depressive symptoms. Risk factors for postnatal depressive symptoms were similar to those for antenatal depressive symptoms, as well as assisted delivery. CONCLUSION: Factors relating to demographic and psychosocial disadvantage were associated with subsequent antenatal and postnatal depressive symptoms in New South Wales, Australia. Our study suggests that screening for probable depression and timely referral for expert assessment of at-risk mothers may be an effective strategy to improve maternal mental health outcomes.

Barriers to antenatal psychosocial assessment and depression screening in private hospital settings.

PROBLEM: The evidence of benefit for antenatal psychosocial assessment and depression screening has been sufficient to lead the implementation of screening in public hospitals in all states of Australia. Details of the implementation of perinatal screening in private obstetric settings is less well known. AIM: As any successful implementation relies on the identification of local barriers, we aimed to determine what perceived or actual barriers may exist for the implementation of evidence-based perinatal screening interventions in private obstetric care, and specifically within small private hospitals. METHOD: The integrative literature review method offers a structured systematic approach to organise, synthesize and critique research from a range of sources. This method was used to determine what barriers have been identified in implementing psychosocial assessment and depression screening with women receiving obstetric care in private hospital settings. FINDINGS: The integrative review findings suggest that barriers to implementing psychosocial screening in the private sector are similar to those experienced in the public sector but may also be influenced by the corporate focus of private services. Barriers were identified among health professionals, within the personal and psychosocial context of women and their families, and at provider or system level. CONCLUSION: Once identified, barriers can be systematically addressed to enhance the success of implementing psychosocial and depression screening in the private sector. Screening is likely to be influenced by the business models and operating systems of private service providers. Health professionals working within this environment need more support to conduct perinatal assessment within this context.

Psychological consequences of pelvic floor trauma following vaginal birth: a qualitative study from two Australian tertiary maternity units.

Vaginal birth may result in damage to the levator ani muscle (LAM) with subsequent pelvic floor dysfunction and there may be accompanying psychological problems. This study examines associations between these somatic injuries and psychological symptoms. A qualitative study using semi-structured interviews to examine the experiences of primiparous women (n = 40) with known LAM trauma was undertaken. Participants were identified from a population of 504 women retrospectively assessed by a perinatal imaging study at two obstetric units in Sydney, Australia. LAM avulsion was diagnosed by 3D/4D translabial ultrasound 3-6 months postpartum. The template consisted of open-ended questions. Main outcome measures were quality of information provided antenatally; intrapartum events; postpartum symptoms; and coping mechanisms. Thematic analysis of maternal experiences was employed to evaluate prevalence of themes. Ten statement categories were identified: (1) limited antenatal education (29/40); (2) no information provided on potential morbidities (36/40); (3) conflicting advice (35/40); (4) traumatized partners (21/40); (5) long-term sexual dysfunction/relationship issues (27/40); (6) no postnatal assessment of injuries (36/40); (7) multiple symptoms of pelvic floor dysfunction (35/40); (8) "putting up" with injuries (36/40); (9) symptoms of post-traumatic stress disorder (PTSD) (27/40); (10) dismissive staff responses (26/40). Women who sustain LAM damage after vaginal birth have reduced quality of life due to psychological and somatic morbidities. PTSD symptoms are common. Clinicians may be unaware of the severity of this damage. Women report they feel traumatized and abandoned because such morbidities were not discussed prior to birth or postpartum.

Oxytocin in the postnatal period: Associations with attachment and maternal caregiving.

BACKGROUND: This study investigated the associations of maternal oxytocin, self-reported attachment insecurity and depressive symptoms with maternal caregiving sensitivity at 3-4months postpartum, observed during the 'free play' and 'reunion' episodes of the Still Face Procedure. METHODS: 112 mothers completed questionnaires and gave blood samples to determine oxytocin plasma levels before (time 1) and after participating in the Still Face Procedure with their infant (time 2). RESULTS: Sensitive maternal caregiving during the free play episode was predicted by 'good' infant behavior; during the reunion episode it was predicted by 'good' infant behavior, higher baseline levels of maternal oxytocin and a greater maternal oxytocin response, or in other words, a larger increase in maternal oxytocin level from time 1 to time 2. With other variables free to vary, baseline maternal oxytocin levels mediated an inverse relation between maternal adult attachment avoidance and sensitive maternal caregiving during the reunion episode. CONCLUSION: Results highlight the association between oxytocin and sensitive maternal caregiving and suggest that oxytocin is a biological mechanism through which maternal attachment insecurity affects early parenting quality.

Genetic Regulation of Maternal Oxytocin Response and Its Influences on Maternal Behavior.

We interrogated the genetic modulation of maternal oxytocin response and its association with maternal behavior using genetic risk scores within the oxytocin receptor (OXTR) gene. We identified a novel SNP, rs968389, to be significantly associated with maternal oxytocin response after a challenging mother-infant interaction task (Still Face Paradigm) and maternal separation anxiety from the infant. Performing a multiallelic analysis across OXTR by calculating a cumulative genetic risk score revealed a significant gene-by-environment (G × E) interaction, with OXTR genetic risk score interacting with adult separation anxiety to modulate levels of maternal sensitivity. Mothers with higher OXTR genetic risk score and adult separation anxiety showed significantly reduced levels of maternal sensitivity during free play with the infant. The same G × E interaction was also observed for the extended OXTR cumulative genetic risk score that included rs968389. Moreover, the extended cumulative OXTR genetic risk score itself was found to be significantly associated with maternal separation anxiety as it specifically relates to the infant. Our results suggest a complex montage of individual and synergistic genetic mediators of maternal behavior. These findings add to specific knowledge about genetic regulation of maternal oxytocin response in relation to maternal adjustment and infant bonding through the first few months of life.

Obstetric and psychosocial risk factors for Australian-born and non-Australian born women and associated pregnancy and birth outcomes: a population based cohort study.

BACKGROUND: One in four Australians is born overseas and 47% are either born overseas or have a parent who was. Obstetric and psychosocial risk factors for these women may differ. METHOD: Data from one Sydney hospital (2012-2013) of all births recorded in the ObstetriX database were analysed (n = 3,092). Demographics, obstetric and psychosocial risk profile, obstetric interventions and complications and selected maternal and neonatal outcomes were examined for women born in Australia and overseas. RESULTS: Women born in Australia were younger, more likely to be primiparous (28.6 v 27.5%), be obese (32.0% v 21.4%), smoke (19.7 % v 3.0%), have an epidural (26.2% v 20.2%) and were less likely to have gestational diabetes mellitus (GDM) (6.8% v 13.7% when compared to non-Australian born women. The highest rates of GDM, Gestational Hypertension (GH) and maternal anaemia were seen in women born in China, the Philippines and Pakistan respectively. Differences were also seen in psychosocial screening between Australian and non-Australian women with Australian-born women more likely to smoke and report a mental health disorder. There was an association between having an Edinburgh Postnatal Depression Scale (EPDS) ≥ 13 and other psychosocial issues, such as thoughts of self-harm, domestic violence, childhood abuse etc. These women were also less likely to breastfeed. Women with an EPDS ≥ 13 at booking compared to women with EPDS ≤12 had a higher chance of being diagnosed with GDM (AOR 1.85 95% CI 1.14-3.0). CONCLUSIONS: There are significant differences in obstetric and psychosocial risk profiles and maternal and neonatal outcomes between Australian-born and non-Australian born women. In particular there appears to be an association between an EPDS of ≥13 and developing GDM, which warrants further investigation.

Adult separation anxiety and unsettled infant behavior: Associations with adverse parenting during childhood and insecure adult attachment.

OBJECTIVE: This study examined the prevalence and correlates of Adult Separation Anxiety Disorder (ASAD) and Adult Separation Anxiety (ASA) symptoms in a sample of first-time mothers with an unsettled infant during the first postpartum year. METHODS: Eighty-three primiparous women admitted to a residential parent-infant program participated in a structured clinical interview for DSM-IV diagnosis and questionnaires assessing ASA symptoms, adult attachment and childhood parenting experiences. Nurses recorded infant behavior using 24-hour charts. RESULTS: The prevalence of ASAD in this sample was 19.3% and women with ASAD were, on average, more likely to be diagnosed with depression and anxiety disorders, report aversive parenting experiences during childhood and show adult attachment style insecurity. Both ASAD and ASA symptoms were predicted by adult attachment anxiety, and ASAD was associated with unsettled infant behavior. Attachment anxiety and attachment avoidance mediated relations between parental over-control and ASAD diagnosis, and between parental abuse and ASAD diagnosis. Attachment anxiety mediated the relation between parental over-control and ASA symptoms, and attachment avoidance mediated the relations of parental over-control and parental abuse with ASA symptoms. CONCLUSIONS: This study highlights the prevalence of ASAD among first time mothers experiencing early parenting difficulties and the roles of childhood parenting experiences and adult attachment style in the development of the disorder. This points to the importance of introducing universal screening for ASAD in postnatal settings, and for the development of targeted interventions.

Separation anxiety, attachment and inter-personal representations: disentangling the role of oxytocin in the perinatal period.

In this paper, we aimed to assess cross-sectionally and longitudinally associations between disturbances in maternal early attachment experiences, symptoms of separation anxiety and depression and oxytocin plasma levels. We examined a mediational model that tested the hypothesis that anxious attachment style arising from the mothers' early bonding experiences with her own parents was associated with high levels of separation anxiety which, via its impact on depression, was associated with reduced levels of oxytocin in the postnatal period. Data is reported on a structured sample of 127 women recruited during pregnancy from a general hospital antenatal clinic and an initial follow up cohort of 57 women who were re-assessed at 3-months post-partum. We found an association between lower oxytocin level in the post partum period and symptoms of separation anxiety and depression during pregnancy, as well as maternal negative interpersonal representations, upbringing attributes and anxious attachment style. Further meditational analysis revealed that the unique association between anxious attachment and depression is mediated by separation anxiety and that depressed mood mediated the relationship between separation anxiety and oxytocin. In conjunction with evidence from the literature suggesting that lower oxytocin level is associated with bonding difficulties, our findings have significant implications for understanding the biological processes underpinning adverse attachment experiences, negative affect state, and mother-to-infant bonding difficulties.

Emotional flooding and hostile discipline in the families of toddlers with disruptive behavior problems.

This study examined the relationship between negative parenting practices and dysfunction in parents' cognitive processing of child affect cues in families of toddlers with disruptive behavior problems. This dysfunction comprised a bias toward the misclassification of child affect as anger (affect appraisal bias) and parents' proneness to emotional flooding (Gottman, 1991, 1993). Participants were families of toddlers (n = 82; 53% male; aged 18-48 months) referred to a tertiary-level health service for the treatment of disruptive behavior problems. Affect appraisal bias was indexed in terms of the discrepancy between rates of child anger coded from video recordings of parent-child interactions and rates of child anger estimated by parents immediately after these interactions. Parenting practices and emotional flooding were assessed using the Parenting Scale and the Parental Flooding Scale. Both hostile and overreactive discipline were positively associated with severity of disruptive behavior problems, however only hostile discipline was associated with the biased appraisal of child affect and emotional flooding. Emotional flooding was found to be a unique predictor of hostile discipline, independent of covariates including the severity of disruptive behavior problems. Variance in hostile discipline was further explained by the interaction between emotional flooding and affect appraisal bias. Emotional flooding appears to be particularly proximal to hostile discipline in the families of toddlers with disruptive behavior problems, consistent with evidence previously reported for nonclinical families.

Maternal deaths in NSW (2000-2006) from nonmedical causes (suicide and trauma) in the first year following birth.

INTRODUCTION: Trauma, including suicide, accidental injury, motor traffic accidents, and homicides, accounts for 73% of all maternal deaths (early and late) in NSW annually. Late maternal deaths are underreported and are not as well documented or acknowledged as early deaths. METHODS: Linked population datasets from births, hospital admissions, and death registrations were analysed for the period from 1 July 2000 to 31 December 2007. RESULTS: There were 552,901 births and a total of 129 maternal deaths. Of these deaths, 37 were early deaths (early MMR of 6.7/100,000) and 92 occurred late (late MMR of 16.6/100,000). Sixty-seven percent of deceased women had a mental health diagnosis and/or a mental health issue related to substance abuse noted. A notable peak in deaths appeared to occur from 9 to 12 months following birth with the odds ratio of a woman dying of nonmedical causes within 9-12 months of birth being 3.8 (95% CI 1.55-9.01) when compared to dying within the first 3 months following birth. CONCLUSION: Perinatal services are often constructed to provide short-term support. Long-term identification and support of women at particular risk of maternal death due to suicide and trauma in the first year following birth may help lower the incidence of late maternal deaths.

Immigrant maternal depression and social networks. A multilevel Bayesian spatial logistic regression in South Western Sydney, Australia.

The purpose is to explore the multilevel spatial distribution of depressive symptoms among migrant mothers in South Western Sydney and to identify any group level associations that could inform subsequent theory building and local public health interventions. Migrant mothers (n=7256) delivering in 2002 and 2003 were assessed at 2-3 weeks after delivery for risk factors for depressive symptoms. The binary outcome variables were Edinburgh Postnatal Depression Scale scores (EPDS) of >9 and >12. Individual level variables included were: financial income, self-reported maternal health, social support network, emotional support, practical support, baby trouble sleeping, baby demanding and baby not content. The group level variable reported here is aggregated social support networks. We used Bayesian hierarchical multilevel spatial modelling with conditional autoregression. Migrant mothers were at higher risk of having depressive symptoms if they lived in a community with predominantly Australian-born mothers and strong social capital as measured by aggregated social networks. These findings suggest that migrant mothers are socially isolated and current home visiting services should be strengthened for migrant mothers living in communities where they may have poor social networks.

Parenting self-efficacy: links with maternal depression, infant behaviour and adult attachment.

BACKGROUND: This study examined predictors of parenting self-efficacy (PSE) in a sample of first-time mothers during the first year after childbirth and evaluated the effect of a brief, intensive, mother-infant residential intervention on PSE and infant behaviour. METHODS: 83 primiparous women with infants aged 0-12 months admitted to a residential parent-infant program participated in a structured clinical interview for DSM-IV diagnosis of depressive and anxiety disorders and completed questionnaires assessing psychological distress, adult attachment and childhood parenting experiences. During their residential stay, nurses recorded infant behaviour using 24-hour charts. RESULTS: Results showed PSE to be inversely correlated with maternal depression, maternal anxiety and attachment insecurity. Low levels of parental abuse during childhood, avoidant attachment, male infant gender and depressive symptom severity were found to predict low PSE. Major depression mediated the relation between attachment insecurity and PSE, but there were no links between PSE and infant behaviour. After the intervention, there was a significant improvement in PSE, with abusive parenting during childhood and depressive symptom severity being predictive of change. CONCLUSIONS: This study highlights the links between maternal psychopathology and maternal background factors such as childhood parenting experiences and attachment style in the development of postnatal PSE. Directions for future research are discussed.

Social exclusion, infant behavior, social isolation, and maternal expectations independently predict maternal depressive symptoms.

The objective of the study was to identify latent variables that can be used to inform theoretical models of perinatal influences on postnatal depressed mood and maternal-infant attachment. A routine survey of mothers with newborn infants was commenced in South Western Sydney in 2000. The survey included the Edinburgh Postnatal Depression Scale (EPDS) and 46 psychosocial and health-related variables. Mothers (n = 15,389) delivering in 2002 and 2003 were surveyed at 2-3 weeks for depressive symptoms. Nonlinear principal components analysis was undertaken to identify dimensions that might represent latent variables. Correlations between latent variables and EPDS >12 were assessed by logistic regression. A five-dimension solution was identified, which accounted for 51% of the variance among the items studied. The five dimensions identified were maternal responsiveness, social exclusion, infant behavior, migrant social isolation, and family size. In addition, the variable maternal expectation contributed significantly to total variance and was included in the regression analysis. Regression on EPDS >12 was predictive for all variables except for maternal responsiveness, which was considered an outcome variable. The findings are consistent with the proposition that social exclusion, infant behavior, social isolation among migrant mothers, and maternal expectations are determinants of maternal mood.

Postnatal depression and socio-demographic risk: factors associated with Edinburgh Depression Scale scores in a metropolitan area of New South Wales, Australia.

OBJECTIVE: The aim of this study was to determine the prevalence and risk factors for postnatal depressive symptoms in women living in metropolitan Sydney, Australia. METHOD: A population-based cross-sectional study of mothers of newborn infants was undertaken during home and community clinic visits in South West Sydney from 2000 to 2004. A comprehensive 45 item survey questionnaire was completed by 29 405 mothers. A self-report Edinburgh Postnatal Depression Scale (EPDS) of depressive symptoms was completed by 25 455 mothers at the first child and family nurse visit. The primary study outcome measures were EPDS scores greater than 9 and greater than 12. RESULTS: At a mean infant age of 2.16 weeks the prevalence of EPDS >9 was 12% and EPDS >12 was 6.2%. Results from multiple logistic regression revealed that EPDS >9 and EPDS > 2 were associated with a maternal country of birth other than Australia, difficult financial situation, living in the suburb one year or less, 'no regret leaving the suburb', unplanned pregnancy, not breastfeeding, and poor rating of mother's own health. Other social demographic factors such as marital status, maternal age, education of mother, or being Aboriginal or a Torres Strait Islander show no significant association with postnatal depressive symptoms. CONCLUSIONS: The results confirm prevalence rates and maternal individual-level risk factors from previous studies. The study contributes to the limited number of studies of postnatal depression and socio-demographic factors. Neighbourhood and community group-level factors may be important and should be studied further.