Prenatal and Postpartum Maternal Psychological Distress and Infant ...

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Mar 10, 2012 - partum distress contributes to cognitive and socio-emotional development. Keywords Infant development 4 Maternal psychological distress 4.
Child Psychiatry Hum Dev (2012) 43:683–714 DOI 10.1007/s10578-012-0291-4 REVIEW PAPER

Prenatal and Postpartum Maternal Psychological Distress and Infant Development: A Systematic Review Dawn Kingston • Suzanne Tough • Heather Whitfield

Published online: 10 March 2012  Springer Science+Business Media, LLC 2012

Abstract Infant development plays a foundational role in optimal child development and health. Some studies have demonstrated an association between maternal psychological distress and infant outcomes, although the main emphasis has been on postpartum depression and infant-maternal attachment. Prevention and early intervention strategies would benefit from an understanding of the influence of both prenatal and postpartum maternal distress on a broader spectrum of infant developmental outcomes. We conducted a systematic review of studies assessing the effect of prenatal and postpartum maternal psychological distress on five aspects of infant development: global; cognitive; behavioral; socio-emotional; and psychomotor. These findings suggest that prenatal distress can have an adverse effect on cognitive, behavioral, and psychomotor development, and that postpartum distress contributes to cognitive and socio-emotional development. Keywords Infant development  Maternal psychological distress  Systematic review  Maternal psychosocial care

Background Healthy child development has been viewed as a necessary foundation for reducing health and social inequities across the life course [1, 2]. Early years programming has been an important strategy for the prevention of developmental problems, largely influenced by an increasing understanding of environmental influences on the neuroplasticity of the young D. Kingston (&) Faculty of Nursing, Rm 5-258 Edmonton Clinic Health Academy, University of Alberta, 11405-87th Avenue, Edmonton, AB T6G 1C9, Canada e-mail: [email protected] S. Tough Faculty of Paediatrics and Community Health Sciences, Centre for Child, Family, and Community Research, University of Calgary, Calgary, AB, Canada H. Whitfield McMaster University, Hamilton, ON, Canada

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brain [2]. From an economic standpoint, investment in the early years in the form of quality education, child development, and parenting programs has shown greater return than investments allocated post-kindergarten [2]. Yet, based on the Early Development Index (EDI), 25–30% of children in Canada enter school with some form of physical, socioemotional, or cognitive-language delay, and Canadian trends reveal an increase in developmental vulnerability in several provinces over the past decade [2, 3]. Advocates suggest that the decline in healthy child development at a time when there has been increased attention in this area implies that greater investment in early years services is required [2]. However, it also compels us to consider earlier influences in a child’s life that have not been sufficiently addressed to date. Tandem to the movement to develop and enhance universal services to support healthy early years’ development has been a growing interest in the long-term effects of risks that occur during pregnancy and the postpartum period on child development. Although maternal health may represent a key point of early, ‘‘upstream’’ intervention, the evidence surrounding early life factors has not been translated into prevention/intervention strategies or policy. The recently released Marmot Review, Fair Society, Healthy Lives, proposed a ‘‘second revolution in the early years’’ to increase the support of parents starting in pregnancy and continuing through primary school [4]. This report recommended ‘‘giving priority to pre- and post-natal interventions that reduce adverse outcomes of pregnancy and infancy’’ (p. 16) [4]. An earlier report by the World Health Organization’s Commission of Social Determinants stated, ‘‘Implementing a more comprehensive approach to early life includes…comprehensive support to and care of mother before, during, and after pregnancy—including interventions that help to address prenatal and postnatal maternal mental health problems’’ (p. 53) [5]. These documents formally acknowledge the important influence of maternal health during the prenatal and postpartum periods in child health and development. Given that maternal psychological distress (e.g., stress, anxiety, depression) in pregnancy is common [6, 7], and a substantial proportion of women who experience distress in pregnancy or during the postpartum period continue to have symptoms into their child’s early years [8–10], maternal psychological distress represents a prevalent, enduring, and modifiable influence that may significantly impact fetal and child development. Interest in the effect of maternal psychological distress on infant outcomes and its underlying mechanisms has surged over the past two decades. While much of the early research in this field focused on studying the impact of postpartum depression (PPD) on outcomes such as maternal-infant interaction and infant temperament, more recent studies have explored the effects of different forms of maternal psychological distress and their timing on a broader array of infant outcomes, including infant development. Some key findings of this body of evidence suggest that: (a) developmental delay in infancy is associated with delay in later childhood stages [11]; (b) predictors of neurodevelopmental delay can be detected during the first 10 months of life [12, 13]; (c) infant developmental delay and its causes are amenable to early intervention targeted at the infant and its family [14, 15]; and (d) intervention aimed at reducing maternal psychological distress can lower the risk of adverse infant developmental outcomes [16]. Very few reviews have synthesized evidence relating prenatal and postpartum maternal psychological distress to infant development. Of these, few are methodologically rigorous, systematic reviews; most address a single form of maternal distress during the prenatal or postpartum period; and, the majority focus on older children. Given the importance of the role of infant development in future child development and health, a substantive review of the impact and magnitude of effect of maternal prenatal and postpartum psychological

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distress on infant development would inform prevention, early intervention, and policy strategies for reducing the risks of developmental delay that occur in a child’s earliest environment. Objectives The objectives of this systematic review were to: (a) assess the relationship between prenatal and postnatal maternal psychological distress and infant development from birth to 12 months; (b) estimate the magnitude of effect of the relationship between various forms of maternal psychological distress and infant developmental outcomes; (c) describe the quality of the evidence for the relationship between maternal psychological distress and infant development; (d) identify gaps in the existing evidence; (e) describe the implications of the review findings; and (f) formulate research, clinical, and policy related recommendations.

Methods Inclusion and Exclusion Criteria and Definitions Studies were included in this review if the: (a) exposure was any form of maternal psychological distress (e.g., anxiety, depression, stress, psychological distress) occurring during pregnancy or the postpartum period (i.e., 1 year following birth); (b) outcome was a measure of child development that was assessed from birth up to and including 12 months and included global indices of development, behavior, cognitive development, socio– socio-emotional development, and psychomotor development; (c) study recruited women and children from developed countries; (d) study was published in English; and, (e) study was a primary study that was published between 1990 and 2010. Studies were excluded from this review if: (a) maternal distress during the prenatal or postpartum period was part of a composite variable that extended beyond 1 year postpartum; (b) the exposure was a pharmacologic treatment for maternal distress; or, (c) the study did not have a comparison group. The categorization of infant outcomes (e.g., as cognitive or behavioral) was based on the investigators’ own descriptions. A global index of development combined a number of developmental components (e.g., socio-emotional, behavioral, cognitive development) into a single index (e.g., Child Behavior Checklist Total Score; Bayley Scales of Infant Development). Trimesters of pregnancy were categorized as first (0–13 weeks gestation), second ([13–26 weeks), and third ([26–40? weeks). Effect sizes were based on Cohen’s guidelines (trivial when r \ 0.10; small when d = 0.20 or r = 0.10–0.30; medium when d = 0.50 or r = 0.30–0.50; and, large when d = 0.80 or r C 0.50) [17]. Odds ratios (ORs) of \1.7 were defined as small, [1.7–2.5 were medium, and [2.5 were large [17]. Search Strategy, Title and Abstract Review, Critical Appraisal, Data Extraction, Analysis The search strategy was developed in consultation with a university-based librarian. Five electronic databases were searched, including Embase, CINAHL, Eric, PsycInfo, and Medline. Reference lists were reviewed and key journals were hand-searched. The search

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encompassed the period from January 1, 1990, to August 10, 2010. The detailed search strategy is available from the authors. The titles and/or abstracts of each article were reviewed independently by 2 individuals based on the a priori inclusion and exclusion criteria. Disagreements related to inclusion or exclusion were resolved by discussion and consensus. In cases where decisions could not be reached based on title or abstract review, the full-text version of the article was retrieved and reviewed. A modified version of the critical appraisal form for observational studies developed by the Scottish Intercollegiate Guideline Network (http://www.sign.ac.uk/methodology/checklists.html) was used to assess the quality of each article. Each study was appraised based on its study design, potential for selection bias, confounders, withdrawals and dropouts, follow-up, blinding, and measurement of exposures and outcomes. The quality of the articles was assessed by 2 independent reviewers with experience in critical appraisal. Disagreements were resolved by consensus. Data were extracted by one reviewer using a standardized data extraction form that was developed for this review. Studies were also reviewed for the potential to conduct a meta-analysis.

Results: Overview The search strategy yielded a total of 17,792 studies with 18 studies having infant outcomes (Fig. 1). These studies recruited participants from a variety of different countries (e.g., New Zealand, Finland, Netherlands, US, Australia, Sweden, Israel). The majority of these studies were published in the past decade (n = 16) with over 60% of these being published in the past 5 years (2005–2010). All but 2 studies were longitudinal and the majority (n = 12) represented community-based samples. Among these 18 studies, most evaluated the effect of maternal distress on infant cognitive (n = 7) or psychomotor (n = 7) development, with fewer assessing the effects on global indices of infant development (n = 2), behavior (n = 2), and socio-emotional development (n = 4). There was a fairly even distribution of the number of studies that assessed prenatal (n = 7) and postpartum maternal distress (n = 8), with 3 studies addressing both. We examined each infant outcome for the potential to conduct a meta-analysis. The diversity of the outcomes (e.g., dichotomous and continuous measures) precluded metaanalysis. We also reviewed the studies for the potential to calculate mean differences where outcomes were dichotomized, but insufficient data were available. As such, a thorough qualitative analysis was conducted. We included all studies in our qualitative analysis because few studies met the inclusion criteria (n = 18), particularly across the various forms of infant development; in addition, their inclusion enabled us to qualitatively describe the heterogeneity that existed between weak and moderate/strong studies [18].

Results: Infant Development Global Indices of Infant Development (Table 1) General Overview of Studies (n = 2) Two longitudinal studies from Finland and New Zealand evaluated the influence of maternal distress on global indices of infant development at 12 months [19, 20]. One study was community-based with half of the mothers having term, small for gestational age infants [20],

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*Articles retrieved through search strategy; title and abstract review (n=17,792)

Studies excluded (n=17,620) due to: (a) not a primary study or a case study (n=5,753); (b) wrong exposure and outcome (n=8,684); (c) wrong exposure (n=2,660); (d) wrong outcome (n=473); (e) correct exposure and outcome but in older population (n=50)

Studies retrieved for more detailed evaluation (n=172) Studies excluded due to recruitment in developing countries; maternal distress measured after 12 months postpartum; maternal and paternal measures of distress not analyzed separately; children