The association of adversity during pregnancy with poor pregnancy and childbirth outcomes is well established [1–3]. The antenatal stressors are broadly related to the intrauterine environment (e.g. nutrition; maternal stress; exposure to smoking, drugs and alcohol), psychosocial experience (e.g. interpersonal violence; loneliness; anxiety and depression), and socioeconomic context (e.g. low income; class; migrant; unemployment; education; housing) a mother has experienced and is currently experiencing [4].
The public health importance of this perinatal adversity is related to its demonstrated impact on multiple domains of childhood and adult outcomes across the life course [5, 6]. Of importance here is the intergenerational nature of this experience of adversity and the impact of mothers’ own childhood experience of adversity on her current pregnancy and childbirth outcomes.
There is an increasing understanding of the impact of exposure to adverse childhood experiences such as child maltreatment and exposure to domestic violence, and health and well-being outcomes across the life course. There is a strong dose-response relationship between exposure to adversity and poor health outcomes, including depression, anxiety, substance use, sexually transmitted diseases, suicide attempts, and a range of chronic diseases. Psychologically stressful experiences often compound those risks during adulthood as a result of ongoing intermittent partner violence, substance use, mental illness and social exclusion [7].
Young-Wolf and colleagues [8] note that there is a “growing body of literature suggesting that adverse childhood experiences are associated with increased mental health risks during pregnancy, including higher depressive symptoms, anxiety, suicidality, and substance use”. There is increasing interest in the role that maternal mental health plays in the intergenerational transmission of experienced adversity [9, 10]. In this study, we will focus on the impact of experienced adversity, as reported during antenatal booking, on perinatal depressive and anxiety symptoms as measured by the Edinburgh Depression Scale.
Pregnancy, childbirth and parenthood present a time of increased stress and vulnerability, placing women at higher risk of developing mood disorders in the perinatal period. If unrecognised or untreated, there are a range of adverse outcomes for women, their newborns and their families, including long- term neuropsychiatric sequelae in offspring. Globally, depression is a leading source of disease burden [11–13], with the prevalence of postpartum depression estimated to be 10–15 per cent worldwide on average, and in some countries can be as high as 40–45 per cent [14]. In Australia, it is estimated that 111,000 mothers were diagnosed with depression [15]. Of these, approximately one in two had perinatal depression, and over one in five was newly diagnosed during the perinatal period.
Significant relationships have been demonstrated between maternal depressive symptoms, their family and social circumstances, factors relating to community integration and ethnicity, and history of professional psychosocial support received [12, 16]. In particular, in the postpartum period, an increasing level of social support provision has a positive effect on decreasing depression risk [16, 17]. During the antenatal period, depressive symptoms are indeed as prevalent amongst pregnant women [18], and its risk has similarly been shown to be reduced with having good social support [19]. Antenatal events and social circumstances, such as disease during pregnancy, family dissatisfaction or social isolation, have also been identified as risk factors for postnatal depression [11, 20]. Maternal depressive symptoms and events in the antenatal period are strongly associated with postnatal depressive symptoms and numerous adverse perinatal outcomes including preterm delivery and low birth weight [19, 21–25].
Psychosocial assessment during pregnancy can identify both risk and protective factors for the development of perinatal mood disorders. The New South Wales (NSW) Safe Start Policy [26] is a universally delivered programme for publicly booked pregnant women in the state of NSW, Australia. The programme incorporates antenatal and postnatal psychosocial assessment and the risk factors identified are used to organise further assessment and intervention. The Safe Start risk stratification framework was developed following a rigorous analysis of literature and expert policy advice. We are not aware of previous empirical studies that have sought to quantify the sub-populations at risk using latent class analysis or other cluster analysis approaches.
The study reported here is part of a translational psychosocial epidemiology study of perinatal adversity in Sydney Australia that aims to design perinatal and early childhood interventions that break the cycle of psychological trauma and adversity. The translational study has established a population cohort in the Sydney Local Health District (SLHD) and South Western Sydney Local Health District (SWSLHD), that will enable long-term modelling of outcomes in the local population and the impact of current and future health service interventions.
SLHD and SWSLHD are located in the Centre, Inner West and South Western regions of metropolitan of Sydney. In Sydney, the SLHD and SWSLHD cover 52% of the metropolitan area, with an estimated population of 1.6 million people of different cultural backgrounds [27, 28]. In the Sydney metropolitan area, more than half of the population spoke English at home (58.4%). Other most common languages spoken at home included Mandarin (4.7%), Arabic (4.0%) and Cantonese (2.9%) [29]. A number of maternal and child health services are provided to all communities across both districts, including those with socioeconomically disadvantaged populations [27, 28].
Here, we examined whether maternal sub-groups can be identified on the basis of their varying experiences of adversity, and whether the risk of antenatal and postnatal depressive symptoms differs between sub-groups, to inform maternal and child health service system redesign in Sydney.