Can J Clin Pharmacol Vol 16 (1) Winter 2009:e15-e22 January 22, 2009 e15 �� 2009 Canadian Society of Pharmacology and Therapeutics. All rights reserved. Depression during Pregnancy: Rates, Risks and Consequences Sheila M. Marcus Section Director Child and Adolescent Psychiatry, Perinatal Mood Disorders Program University of Michigan, Ann Arbor, Michigan, USA ABSTRACT Affective illness is common in women, and the puerperium is a time of particular vulnerability. Gender differences in the expression of affective disorders have been attributed to the impact of hormonal influence, socialization, and genetics. Dramatic fluctuations in gonadal hormones that occur following childbirth, influences the increased incidence of mood disorders during this time. Numerous tools including the Edinburgh Postpartum Depression Scale can be used to screen for depression during pregnancy and postpartum. While screening tools may assist with appropriately identifying women who should be further assessed, their use alone does not significantly increase treatment seeking in women, even when their providers are notified about risk. Many studies demonstrate that only a small number (18%) of women who meet criteria for major depressive disorder seek treatment during pregnancy and postpartum. Additionally, common symptoms of depression (sleep, energy and appetite change) may be misinterpreted as normative experiences of pregnancy. Treatment engagement is important as untreated depression during pregnancy may have unfavorable outcomes for both women and children. Complications of pregnancy associated with depression include: inadequate weight gain, under utilization of prenatal care, increased substance use, and premature birth. Human studies demonstrate that perceived life-event stress, as well as depression and anxiety predicted lower birth weight, decreased Apgar scores, and smaller head circumference, and small for gestational age babies. Postpartum depression (PPD) is a common clinical disorder occurring in 15% of deliveries, making it one of the most frequent conditions to complicate pregnancy. Risk factors include past personal or family history of depression, sing marital status, poor health functioning, lower SES, and alcohol use. Women who have a prior history of postpartum depression, particularly with features of bipolarity or psychosis may be at particularly high risk. Introduction The perinatal period is a time of substantial vulnerability to affective illness. Gender differences for many psychiatric disorders have been attributed to genetics, gender role socialization, and to hormonal influences.1 During the perinatal period dramatic fluctuations in gonadal hormones influence the presentation of affective illness.1 Rapid fluctuation in hormone levels during pregnancy, and more dramatically, the rapid fall during postpartum increases the prevalence of mood disorders during this time.

Depression during pregnancy: rates, risks and consequences ��� Motherisk Update 2008 Can J Clin Pharmacol Vol 16 (1) Winter 2009:e15-e22 January 22, 2009 �� 2009 Canadian Society of Pharmacology and Therapeutics. All rights reserved. e16 The substantial increase in hospitalization postpartum has been attributed to mood disorders3 and most psychosis which occurs during the postpartum is affective in nature. Screening Tools Recent studies suggest that 10% of gravid women meet criteria for major depression4,5 and up to 18% show elevated depressive symptomatology during gestation.6 Variable prevalence rates noted within the scientific literature reflect the variety of screening instruments used and whether they reflect data collected by self-report or trained researchers. Additionally, the timing of the collection of the data relative to the duration of pregnancy or time since birth lends variable prevalence rates. Common self- report instruments include the Center for Epidemiologic Studies Depression Scale (CES-D)7,8 and the Edinburgh Postnatal Depression Scale (EPDS).9,10 Of these, the EPDS is more specific to the perinatal period and less reliant on somatic symptoms (such as sleep and appetite dysregulation) which are normative in pregnancy. The Beck Depression Inventory (BDI) is also commonly used as a longitudinal metric for depression.11 The Structured Clinical Interview for Depression (SCID) is an instrument administered by researchers trained in its use and while it is considered the ���gold standard��� for the research diagnosis of depression, its utility is quite limited in primary care settings.12,13 Clinical Features and Detection Rates The clinical features of major depressive disorder (MDD) during pregnancy are identical to those of this illness during any other time of a woman���s life. These symptoms include 8 of 14 symptoms of depression that are present for a period of no less than 2 weeks.14 Women who may attribute insomnia or appetite dysregulation to normative symptoms of pregnancy commonly overlook symptoms of depressed mood and anhedonia. The stigma associated with depression and the asynchrony between the woman���s expectation of bliss during a wanted pregnancy, and her symptoms of sadness and irritability cause many women to under-report these symptoms. Additionally, providers caring for women who are preoccupied with the myriad of clinical information that must be collected during the very brief prenatal visit (fundal