POSTPARTUM DISORDERS 20 Running head: POSTPARTUM DISORDERS 1 Postpartum Disorders and the

POSTPARTUM DISORDERS 20
Running head: POSTPARTUM DISORDERS 1
Postpartum Disorders and the Need for Discrete Diagnostic Criteria
First and Last Name of Student
National University
Psychology 480 – Senior Project
.
Date
Abstract
It has been observed since the time of Hippocrates that women are particularly susceptible to mental illness following childbirth. This form of mental illness is especially worrisome due to its wide-ranging adverse effects on society and potentially tragic outcomes for individuals and families. Sadly, the lack of agreement about the nature of these mental disturbances has led to inadequate diagnosis and treatment of postpartum disorders. Research reveals that generally accepted forms of—and criteria for—postpartum disorders exist; there are both biological and psychosocial risk factors; and postpartum disorders are found around the world. Women suffering from postpartum disorders are at a greater risk for committing suicide and infanticide, and the legal treatment of the latter is inconsistent at best and barbaric at worst. Though there is no doubt that more research is needed, sufficient reliable information exists to strongly suggest the need for a paradigm shift in the American psychiatric community with respect to the recognition and classification of these potentially dangerous disorders.
Table of Contents
Abstract 2
Background of the Study 5
Statement of the Problem 7
Definition of Terms 10
Limitations of the Study 10
Theoretical Framework 11
Review of Literature 12
Categorization of Postpartum Disorders 12
Postpartum Blues 12
Postpartum Depression 13
Postpartum Psychosis 15
Risk Factors for Development of Postpartum Disorders 17
Psychosocial Risk Factors 17
Biological Risk Factors 21
Genetics 21
Hormones 22
Cross-Cultural Review of Postpartum Disorders 24
Neonaticide, Infanticide, and Filicide 26
Discussion, Conclusion, and Recommendations 29
References 32
List of Tables
Table 1 – Cross-Cultural Prevalence of Postpartum Blues 24
Table 2 – Cross-Cultural Prevalence of Postpartum Depression 25
Postpartum Disorders and the Need for Discrete Diagnostic Criteria
Background of the Study
In recent years, the legal cases of Susan Smith and Andrea Yates have brought into focus the disquieting and alarming reality that women are not above killing their own children. The idea that a woman could kill her own child is perplexing—especially in light of the unwavering maternal love and protectiveness that women are expected to feel toward their children from the moment they are born. In both the Smith and Yates cases, mental illness was identified as the precipitating factor causing these women to end their children’s lives. The Yates case is of particular interest because of the form her mental illness took—namely, “postpartum depression that had resulted in two hospitalizations and two suicide attempts” (Charatan & Eaton, 2002, p. 634). Fearing that Yates was suicidal, three months following the birth of her last child, and three months prior to killing her children, Yates’ treating psychiatrist had her hospitalized and treated with antipsychotic medication (Charatan & Eaton). Despite Yates’ history of mental illness and her psychiatrist’s testimony attesting to her mental illness, Yates was found guilty and sentenced to life in prison.
Childbirth marks a period of profound transition in a woman’s life as she experiences significant and rapid biological, social, and psychological changes (Born, Zinga & Steiner, 2004). During the period following childbirth (known as the postpartum period, or puerperium), women are incredibly susceptible to various levels of emotional and psychological distress. In fact, psychiatric hospital admission rates are higher for women during the postpartum period than at any other time of a woman’s life (Born et al.; Shoeb & Hassan, 1990).
Postpartum disturbances have been recognized since the time of Hippocrates (Millis & Kornblith, 1992; Okano, 1999) and postpartum disorders have been documented as early as the 1850s (Jones, 1990). The range of emotions experienced following childbirth has been grouped according to onset, intensity, and duration (Jones). From the least to most severe, postpartum disorders include three main categories: postpartum blues, postpartum depression, and postpartum psychosis (Gale & Harlow, 2003). Despite the recognition and general organization of postpartum disorders, controversy persists about whether postpartum disorders are discrete and separate from other mood and psychotic disorders and if they should therefore have their own classification as mental illnesses (Born et al., 2004; Robertson & Lyons, 2003).
The reasons for the controversy surrounding the characterization of postpartum disorders as discrete mental illnesses are many. One of the difficulties in distinguishing postpartum disorders from other already classified mental illnesses is that presenting physical symptoms—such as shifts in appetite, sleep disturbances and lack of sexual interest—are considered normal following childbirth (Bright, 1994; Nonacs & Cohen, 1998; Robertson & Lyons, 2003). Additionally, symptoms of psychotic episodes are similar regardless of whether they occur postpartum or at another time (Born et al., 2004; Millis & Kornblith, 1992). Something as seemingly basic as defining what constitutes the postpartum period is also challenging and, as a result, definitions are inconsistent (Chaudron & Pies, 2003). For example, the United States National Library of Medicine defines puerperium as the period of up to eight weeks following delivery (Born et al.), but clinically it usually includes a full twelve months after delivery (Born et al.; Chaudron & Pies).
Although it has been recognized that women are particularly vulnerable to psychological disturbances following childbirth, in 1926 the American Psychological Association and American Medical Association eliminated postpartum psychosis from the list of mental disorders because “no distinct syndrome existed which showed a connection between a psychiatric disorder and childbirth” (Connell, 2002, p. 152). Postpartum disorders are therefore not uniquely defined in the Diagnostic and Statistical Manual, Fourth Edition (DSM-IV), but instead are listed casually as examples of other disorders in the “not otherwise specified” category (Agrawal, Bhatia & Malik, 1997; Seyfried & Marcus, 2003; Steiner, 1998). A consequence of this method of diagnosing postpartum disturbances is inadequate recognition, prevention, and treatment, the repercussions of which can be quite serious (Kumar, 1994; Millis & Kornblith, 1992).
Statement of the Problem
Postpartum disorders present a complex predicament for women and their families. When a woman experiences emotional dilemmas following childbirth it damages her confidence to care for her infant, puts strain on the marital relationship (if present), and hinders her quality of life (Adewuya, Eegunranti & Lawal, 2005). An outcome for many women suffering from postpartum depression is “low self-esteem compounded by a sense of responsibility for their illness” (Millis & Kornblith, 1992, p. 193). New mothers often experience feelings of isolation. Due to the pressure women feel to be “perfect” mothers and the belief that they should be experiencing nothing but joy at the birth of their child, women often keep their troubling feelings to themselves, further exacerbating their struggle (Millis & Kornblith). Women afflicted with postpartum mental illness may get to the point where they become a danger to themselves. The risk of suicide for women admitted to a psychiatric hospital due to psychological issues in the first year following childbirth is seventeen times that of the general population (Ahokas & Aito, 1999). Women who are suicidal during the postpartum period are usually suffering from psychosis (Appleby, 1996) and represent psychiatric emergencies requiring hospitalization and treatment (Born et al., 2004; Clayton, 2004).
In addition to the general and more serious problems facing women suffering from postpartum illnesses, infant development is also of significant concern. Women who have a reduced emotional capacity are often unable to effectively bond with their infants (Millis & Kornblith, 1992). Additionally, women with postpartum depression are more “hostile toward their infants and less likely to interact with them and respond to their needs” (Born et al., 2004, p.34). Postpartum depression negatively influences infant cognitive, social, and emotional development (Adewuya et al., 2005), likely due to the impaired mother-infant bonding. One study found that “infants whose mothers were effectively unavailable due to postpartum depression were more likely to exhibit developmental problems between the ages of four and eight” (Millis & Kornblith, p. 195).
The greatest danger presented by postpartum disorders is the threat posed to the life of the infant. Child abuse and neglect are more common among women with postpartum illnesses (Gold, 2001). While infanticide and filicide committed because of postpartum depression is rare (Gold), it is more likely that a woman suffering from postpartum psychosis may commit such an act (Gold; Seyfried & Marcus, 2003). It is estimated that as much as 4% of women suffering from postpartum psychosis will commit infanticide (Ahokas & Aito, 1999; Gold).
In the American legal system, disparity exists with respect to the treatment of women who commit infanticide due to postpartum mental illness, and postpartum psychosis has traditionally not been a viable defense (Connell, 2002). Postpartum psychosis is hard to prove in insanity defenses due to the lack of agreement in the medical community about the parameters of the diagnosis (Connell). The courts look to medical experts to substantiate mental illness and since the research is limited and the psychiatric community divided, women are not treated fairly or consistently in the legal system (Connell; Spinelli, 2004). “Each act is judged in isolation” (Spinelli, p. 1549), the result of which has been punishments ranging from a couple of years in prison to lifetime incarceration, and even the death penalty (Manchester, 2003; Oberman, 2003; Spinelli).
Postpartum disorders are psychologically damaging to women and children and can even jeopardize their lives. Owing to the current disagreement about whether or not postpartum disorders are separate and distinct mental illnesses, healthcare professionals are not adequately trained to recognize postpartum disorders (Millis & Kornblith, 1992). Therefore, these disorders are “underrecognized, underdiagnosed and undertreated” (Born et al., 2004, p. 29). The tragic case of Andrea Yates highlights the crucial need for discrete diagnostic criteria. This study will undertake an examination of research that explores the characteristics of—and risk factors contributing to—postpartum disorders, and a review of the cross-cultural prevalence of postpartum disorders and their relationship to infanticide, thereby documenting the need for discrete postpartum diagnoses. Enough evidence exists to justify and satisfy the need, although more research is also indicated.
Definition of Terms
Estradiol: (oestradiol): potent oestogenic steroid sex hormone secreted by the ovaries (Colman, 2009).
Filicide: killing of one’s son or daughter (Sonanes & Stevenson, 2005).
Infanticide: deliberate killing of an infant, usually newborn (Last, 2007).
Neonaticide: act of killing a baby within the first 24 hours of its life (Law & Martin, 2009).
Postpartum: relating to the period of a few days immediately after birth (Oxford, 2010a)
Primipara: of or related to a woman who is giving birth for the first time (Barber, 2004)
Puerperium: the period of up to about six weeks after childbirth, during which the mother’s body returns to its pre-pregnant state and her uterus returns to its normal size (Oxford, 2010b)
Limitations of the Study
Uncertainty regarding the classification and clinical presentation of postpartum disorders has been a major hindrance to the study of these illnesses. Due to the lack of uniform criteria, studies within the United States have been limited, and the methods for characterizing women with presenting symptoms have varied from study to study. Studies conducted in the United States and abroad have used inconsistent criteria by which to identify and measure the prevalence of postpartum disorders. While the general characteristics of postpartum disorders are similar across the board, existing variations make it difficult to rely on the conclusions drawn from the studies examined.
Additionally, when looked at as a whole, some of the studies regarding the causes of postpartum illnesses have been somewhat inconclusive. For example, some studies support certain hormonal characteristics as precipitating factors to the development of postpartum psychosis, while others do not support this conclusion. It is clear that additional research is required to definitively characterize the risk factors connected to postpartum disorders.
Theoretical Framework
The scientific study of postpartum disorders is in its relative infancy. To date, studies have attempted to identify the many risk factors for postpartum illness in order to pinpoint what causes them. In the United States, postpartum disorders have mostly been deemed psychosocial problems, but mounting evidence suggests biology is a huge component (Millis & Kornblith, 1992). It is clear that a woman’s susceptibility to postpartum disorders includes biological, psychosocial, personality, and other circumstantial factors, although the relative impact of each component is unknown (Glover & Kammerer, 2004). The specific nature of the disorder, and whether it is characterized as depressive or psychotic, seems to indicate which factors are the most influential in its development. By virtue of the fact that this study seeks to explore and understand postpartum disorders from a holistic viewpoint, an analysis of risk factors from biological and psychosocial perspectives will be included.
Review of Literature
Categorization of Postpartum Disorders
Postpartum disorders are organized into three main categories, including postpartum blues, postpartum depression, and postpartum psychosis. Postpartum disorders can be thought of as three forms of the same illness occurring along a continuum; they share similar symptoms differing mainly in the degree of their severity. Gaining a better understanding of postpartum disorders requires elaboration on the three categories and the most prevalent symptoms of each.
Postpartum blues. Postpartum blues, also referred to as “maternity blues, mother’s blues, baby blues, and third-, fourth-, or tenth-day blues” (Bright, 1994, p. 596), is the most common postpartum condition and is not thought of as pathological due to its short duration and its high frequency of occurrence (Bright; Millis & Kornblith, 1992). Postpartum blues is thought to affect anywhere from 30%–80% of women, with onset occurring within a few days of delivery and typically resolving within two weeks (Bright; Clayton, 2004; Harris, 1994; Millis & Kornblith; Seyfried & Marcus, 2003). Symptoms of postpartum blues include depressed mood, tearfulness, emotional lability, anxiety, sleep disturbance, fatigue, and feelings of confusion (Clayton; Harris; Millis & Kornblith; Seyfried & Marcus). Postpartum blues is considered transient and not likely to affect a woman’s normal functioning or her ability to care for herself or her infant (Bright; Steiner, 1998). Due to the normalcy of postpartum blues and the relatively minor symptoms, the condition does not usually require professional care (Bright). Treatment might include “validation, reassurance, assistance with self and baby care, and observation for worsening symptoms” (Millis & Kornblith, p. 193). Normally, these can generally be provided by family members.
Postpartum depression. Postpartum depression is the second level within the continuum of postpartum disorders and is a more serious condition often precipitated by postpartum blues. The prevalence rate of postpartum depression is 7%–22% (Ahokas & Aito, 1999; Born et al., 2004; Clayton, 2004; Harris, 1994; Millis & Kornblith, 1992; Seyfried & Marcus, 2003; Steiner, 1998) and occurs within a few weeks to six months following delivery (Ahokas & Aito; Born et al.; Seyfried & Marcus; Steiner). Some, however, believe women are susceptible for the entire first year after childbirth (Clayton; Millis & Kornblith). Symptoms of postpartum depression are very similar to, and almost indistinguishable from, symptoms of depression occurring at other times (Gale & Harlow, 2003; Seyfried & Marcus), which is one of the main reasons there is no discrete diagnostic category for postpartum depression. More specifically, symptoms are characterized by a “downward spiral” that includes feelings of sadness, depressed mood, anger, feeling overwhelmed, anxiety, and loneliness (Robertson & Lyons, 2003, p.414). In cases of major depression, symptoms may also include agitation, auditory hallucinations, delusions and disorientation (Agrawal et al., 1997).
While many of the symptoms of postpartum depression are characteristic of depression occurring at others times, postpartum depression does have distinguishing features. The condition of postpartum depression is different from depression occurring at other times simply because it is precipitated by the specific life event of giving birth (Gale & Harlow, 2003). This is important because some of the feelings contributing to the depression are particular to the birth of a child, including feelings of guilt and inadequacy about being a new mother (Gale & Harlow). Also present may be intrusive, aggressive and obsessive thoughts about harming the baby (Gale & Harlow; Seyfried & Marcus, 2003) or fears about something else harming the baby accompanied by compulsive checking behavior (Born et al., 2004). These fears may contribute to the greater prevalence of anxiety that occurs with postpartum depression as compared to the frequency with which it occurs in depression experienced at other times (Gale & Harlow; Seyfried & Marcus).
Treatment of postpartum depression is dependent on the severity of symptoms and can include psychotherapy, pharmacotherapy, and electro-convulsive therapy (ECT) (Clayton, 2004). With respect to psychotherapy, interpersonal and cognitive behavioral approaches have both been effective in improving depressive symptoms, although, in general, women have been less responsive to treatment in the postpartum period than when experiencing depression at other times (Clayton). Additionally, for some unknown reason, women with postpartum depression take longer to respond to pharmacotherapy than when treated for depression at other times (Gold, 2001). A cost benefit analysis needs to be done when determining whether to use pharmacotherapy because medicine is excreted in breast milk and may have an impact on a breastfeeding infant, although no clinical studies have been performed to determine what that impact might be (Clayton). Women have a 50% chance of re-experiencing postpartum depression following subsequent deliveries (Gold).
Postpartum psychosis. Postpartum psychosis is the least prevalent but most serious of the postpartum disorders (Bright, 1994; Robertson, Jones & Benjamin, 2000). Postpartum psychosis occurs in 1–2 cases per 1000 deliveries (Agrawal et al., 1997; Meakin, Brockington, & Lynch, 1995; Millis & Kornblith, 1992; Nonacs & Cohen, 1998; Terp & Mortensen, 1998) and generally has a sudden and rapid onset within the first few days postpartum (Agrawal et al.; Gale & Harlow, 2003; Meakin et al.; Millis & Kornblith; Nonacs & Cohen; Steiner, 1998), although it can occur as late as several months following delivery (Ahokas & Aito, 1999; Terp & Mortensen). Though the first occurrence of postpartum psychosis usually follows primiparity, it is possible that it will not occur until after several pregnancies (Robertson & Lyons, 2003).
Postpartum psychosis seriously affects a woman’s ability to function (Steiner, 1998). It is often delineated into major depression with psychotic features, bipolar disorder and schizoaffective disorder (Clayton, 2004; Okano; 1999). Because each of the postpartum disorders is on the same continuum, some of the symptoms of postpartum psychosis may be similar to those of postpartum depression, with the differences often being the degree to which the symptoms are experienced. Generally, postpartum psychosis is characterized by sudden onset and just as sudden cessation with varying degrees of mental illness throughout the postpartum period (Connell, 2002). In Western countries, symptoms tend to be more affective in nature and mania is very common. Those characterized as having postpartum schizophrenia have symptoms of disorientation, agitation, hallucinations, and formal thought disorder (Agrawal et al., 1997). Characteristics of other postpartum psychoses include delusions, visual and auditory hallucinations, disorientation, perplexity, and lability of mood and blunting of affect (Agrawal et al.; Robertson et al., 2000). Delusions and depressive thoughts may center on distorted thinking of oneself as a bad mother who is incapable of self-care and caring for her child (Haapasalo & Petäjä, 1999). Delusions are also often connected to thoughts of harming the infant (Chaudron & Pies, 2003) and/or fears that the infant is “possessed, has special powers, is divine, or is dead” (Born et al., 2004, p. 32).
Many of the symptoms of postpartum psychosis resonate with the symptoms of psychosis experienced at other times. There are, however, characteristics that set postpartum psychosis apart. For example, women afflicted with psychosis during the postpartum period “have been shown to be more delusional, disoriented, and agitated with greater frequency than men or women suffering from psychosis unrelated to childbirth” (Connell, 2002, p. 146). Unusual symptoms, such as tactile, olfactory, and visual hallucinations, also occur (Spinelli, 2004). Particularly concerning is the tendency for symptoms to wax and wane, where the woman appears to be okay one minute and is clearly psychotic the next (Chaudron & Pies, 2003; Spinelli). This makes it more complicated to diagnose the condition of postpartum psychosis and adds to the confusion regarding the legitimacy of the diagnosis (Macfarlane, 2003).
Women suffering from postpartum psychosis pose a danger to themselves and their infants (Chaudron & Pies, 2003; Macfarlane, 2003; Steiner, 1998; Terp, Engholm, & Moller, 1999) and consequently hospitalization is necessary (Robertson & Lyons, 2003; Steiner). Treatment of postpartum psychosis consists of antipsychotic medication and/or mood stabilizers (Clayton, 2004; Seyfried & Marcus, 2003), and may include ECT (Seyfried & Marcus). The prognosis for those who receive treatment is very positive (Pfuhlmann, Franzek, Beckmann, & Stober, 1999; Robertson & Lyons). Within two to three months as many as 95% of women improve (Bright, 1994) and most usually return to normal functioning (Robertson & Lyons). The long-term outcome is better for those suffering from postpartum psychosis than those suffering from psychosis occurring at other times (Terp et al.), which may be another distinguishing feature of postpartum psychosis. Unfortunately, although the prognosis is favorable, reoccurrence of postpartum psychosis is common following subsequent deliveries, with reoccurrence rates ranging from 17% to as high as 80% (Gold, 2001; Pfuhlmann et al.; Robertson & Lyons; Terp et al.).
Risk Factors for the Development of Postpartum Disorders
Like most mental illnesses, the etiology of postpartum disorders is multifactorial; there is no single risk factor for their onset and development. Historically, in the United States, psychosocial risk factors have been thought to be the most prevalent causes of postpartum disorders (Millis & Kornblith, 1992). However, in keeping with the tradition of Hippocrates (who thought postpartum disorders were related to a blood dysfunction in the brain), current research is also focusing on a biological etiology, especially with respect to postpartum psychosis, and mounting evidence suggests biological factors are a huge component (Millis & Kornblith).
Psychosocial risk factors. In general, the most common psychosocial risk factor for the development of postpartum disorders is the presence of major life stressors during or following pregnancy (Born et al., 2004; Marks, Wieck, & Checkley, 1991; Millis & Kornblith, 1992). According to one study, “82% of women admitted to hospital within 90 days of delivery had long-term difficulties or life events” (Marks et al., p. 45). Serious life stressors might include unplanned pregnancy, social isolation, an unsupportive spouse, being a single mother, low-income status (Born et al.; Boury, Larkin, & Krummel, 2004; Bright, 1994; Clayton, 2004; Harris, 1994; Millis & Kornblith; Seyfried & Marcus, 2003) and having a new infant with significant health problems or a highly irritable temperament (Born et al.; Millis & Kornblith). These life stressors likely play a larger role in the onset of postpartum depression than in postpartum psychosis (Marks et al.).
Sleep deprivation occurring during late pregnancy, labor, and the period immediately following childbirth is another life stressor that may contribute to postpartum disorders (Born et al., 2004; Sharma & Mazmanian, 2003). This period is marked by significant sleep disturbance, especially in primiparous women (Sharma & Mazmanian). Hippocrates even noted that sleep disruption was connected with one postpartum woman in particular who was thought to have died because of postpartum mania. Her symptoms included, “insomnia on day 1, restlessness, and loss of sleep on the 6th day postpartum followed by delirium 5 days later and then coma” (Sharma & Mazmanian, p. 100). Modern studies on the relationship between sleep disturbance and postpartum disorders are limited, but do support a connection (Sharma & Mazmanian).
Looking at each of the postpartum disorders independently, it is apparent that certain psychosocial risk factors are specific precipitants to particular postpartum disorders. Aside from low-income status, marital discord, and mood disturbance before or during pregnancy, there are not many identified psychosocial risk factors for postpartum blues (Seyfried & Marcus, 2003). As mentioned previously, postpartum blues is very common and not particularly concerning so there is not much data focusing specifically on the risk factors for developing the blues. However, it does appear that certain psychosocial elements pose a greater risk to developing postpartum depression and postpartum psychosis.
In the development of postpartum depression, low-economic status is a particularly strong risk factor (Boury et al., 2004; Clayton, 2004). Those in a lower socioeconomic bracket have higher rates of depression generally, which puts them at a greater risk for depression following childbirth (Boury et al.). In addition, obesity is more prevalent in low-income women, which makes them susceptible to higher postpartum weight. Higher postpartum weight contributes to feelings of depression due to pressures to fit within a thin ideal and feelings of failure because of the inability to conform to this ideal (Boury et al.). A combination of life stressors, depressive symptoms, and low-income influence “financial stress, lack of employment opportunities, possible social isolation, transportation problems, limited opportunity for recreational or exercise activities, and lack of relief for the constant demands of raising small children” (Boury et al., p. 28).
Certain personality characteristics are also risk factors for the development of postpartum depression, such as neuroticism (Dennis & Boyce, 2004; Harris, 1994), interpersonal sensitivity, low self-esteem, and a negative dysfunctional cognitive style (Dennis & Boyce). These characteristics exacerbate the conflicting feelings that women have about motherhood in terms of how they think they are supposed to feel (i.e., happy and overjoyed) and the reality of their depressed and confused feelings (Robertson & Lyons, 2003). Poor coping skills together with these challenging personality traits aggravate feelings of failure leading to more depression (Boury et al., 2004).
A few of the psychosocial risk factors for postpartum depression are also risk factors for postpartum psychosis, although the relationship to postpartum psychosis is not as great. These coincident risk factors include low-economic status, unplanned pregnancy, and a strained marital relationship (Agrawal et al., 1997). The gender of the child may also have an impact. In one study, the majority of women suffering from postpartum psychosis had given birth to a female child. This may act as a stressor for those who are culturally pre-disposed to want, and expect, to give birth to a male child (Agrawal et al.).
Although a certain degree of connection between these risk factors and postpartum psychosis has been found, the most prevalent psychosocial risk factors in the development of postpartum psychosis are primiparity (Agrawal et al., 1997; Bright, 1994; Harris, 1994; Marks et al., 1991; Seyfried & Marcus, 2003) and a history of bipolar disorder (Bright; Chaudron & Pies, 2003; Harris; Marks et al.; Robertson, Jones, Haque, Holder, & Craddock, 2005). The majority of studies have found that women suffering from postpartum psychosis are first time mothers. Additionally, a personal history of mental illness, particularly of bipolar disorder, put women at a greater risk for developing postpartum psychosis. One study found the prevalence of postpartum psychosis to be 260 cases per 1000 among women with histories of bipolar disorder compared to the 1–2 per 1000 among the general population (Chaudron & Pies). Another study suggests that as many as half of women with bipolar histories will suffer from postpartum psychosis immediately following childbirth (Robertson et al., 2005).
Biological risk factors. Biological risk factors for the development of postpartum disorders have been receiving increased attention. There is no single biological risk factor identified in the development of postpartum disorders (Seyfried & Marcus, 2003). Most of the biological elements studied thus far are categorized into two main groups: genetics and hormones. Strong evidence suggests that both may play a role in the development of postpartum disorders, although more conclusive studies are required to draw a definitive connection to these risk factors and mental illness following childbirth.
Genetics. According to one study, “clinical and genetic evidence suggests that puerperal psychosis probably represents the manifestation of an affective disorder diathesis with the episode being precipitated by childbirth” (Craddock, Brockington, Mant, Parfitt, McGuffin, & Owen, 1994, p. 359). Many family studies, including twin and adoption studies, point to a strong genetic link to the onset and development of postpartum disorders (Born et al., 2004; Craddock et al.; Seyfried & Marcus, 2003; Steiner, 1998). The prevalence of having a family history of mood-related disorders in first-degree relatives is much higher in women suffering from postpartum disorders than in the general population (Born et al.; Steiner). A family history of bipolar disorder and postpartum psychosis puts women at an even greater risk for suffering from postpartum psychosis (Born et al.; Craddock et al.; Glover & Kammerer, 2004; Millis & Kornblith, 1992). In fact, women with a family history of postpartum psychosis are more than 50% likely to have an episode themselves (Born et al.). One study has found a particular gene in the serotonin transporter that has been shown to have a significant influence on the susceptibility to postpartum psychosis (Glover & Kammerer). While the link between family history and postpartum disorders is clear, more studies are needed to better understand the genetic factors that contribute to their onset.
Hormones. Studies exist that examine the influence of changing hormones on the development of postpartum disorders. More specifically, researchers have focused on the effects of estrogen and progesterone levels and thyroid hormone functioning in cases of postpartum disorders. Changes in the levels of estrogen and progesterone have an impact on neurotransmitter functioning (Clayton, 2004; Harris, 1994; Meakin et al., 1995; Millis & Kornblith, 1992; Steiner, 1998) and estrogen has antidepressant as well as antipsychotic influences (Ahokas & Aito, 1999). Changes in estrogen and progesterone levels can therefore affect mood and behavior, and have the potential to induce serious mood reactions, especially in women who are susceptible to depression (Born et al., 2004). During pregnancy, there is a slow rise in estrogen and progesterone levels to several hundred times normal levels, followed by a sudden and rapid drop after delivery (Ahokas & Aito; Harris; Millis & Kornblith). Some women may be more greatly impacted by this substantial drop in hormone levels and it may be associated with postpartum depression and psychosis in women who are otherwise vulnerable to the development of mental illness (Ahokas & Aito; Glover & Kammerer, 2004; Harris; Millis & Kornblith).
One study conducted on two postpartum psychotic women showed both of them were unresponsive to anti-psychotic medication (Ahokas & Aito, 1999). These women were deficient in estrogen levels following childbirth. These women were very responsive to estradiol treatment and symptoms quickly dissipated showing that there may in fact be a significant connection to a drop in estrogen levels and postpartum psychosis. Both women relapsed after discontinuing the estradiol treatment further supporting the connection between estrogen deficiency and postpartum psychosis.
In another study consisting of four women suffering from postpartum psychosis, the relationship between their illnesses and a drop in hormones was challenged (England, Richardson, & Brockington, 1998). Each woman in this study delivered prematurely when hormone levels were approximately half the peak levels typically attained by the end of pregnancy. Therefore, the precipitous fall in hormone levels did not necessarily occur in these women but they still developed postpartum psychosis. It is highly likely that estrogen and progesterone play a significant role in postpartum psychosis, but additional studies are needed to further illustrate and explain the relationship.
Another important link between hormones and postpartum disorders is the evident effect of thyroid hormone dysfunction on the development of mental illness in the puerperium. Various mental conditions and disorders such as anxiety, depression, mania, hypomania, obsessive-compulsive symptoms, delirium, impaired attention and memory, paranoid ideation and auditory or visual hallucinations have been linked to hyperthyroidism and hypothyroidism (Placidi, Boldrini, Patronelli, Fiore, Chiovato, Perugi, et al., 1998). Many of these symptoms are present in women suffering from postpartum depression, and it has been shown that “transient hypothyroidism, sometimes preceded by hyperthyroidism, occurs in up to 5% of women in the postpartum year, reaching a peak at four to five months” (Harris, 1994, p. 290). There is a connection between thyroid disorders and postpartum disorders, especially major depression, psychotic depression and/or severe psychosis (Okano, 1999). As many as 1% of postpartum women experience mood disorders because of thyroid dysfunction (Steiner, 1998). In addition to hypothyroidism and hyperthyroidism, studies have found a connection between the presence of thyroid autoantibodies and postpartum depression (Glover & Kammerer, 2004).
Cross-Cultural Review of Postpartum Disorders
Many studies make it clear that postpartum disorders are not unique to Western societies. Although there are identified differences with respect to prevalence rates, symptoms, and risk factors, most cultures recognize the existence of the blues, depression, and psychosis triggered by childbirth. The prevalence of postpartum blues appears to be higher in Western countries, but it has been found in every country where it has been examined (Rondón, 2003). See Table 1 for a summary of cross-cultural prevalence rates of postpartum blues.
Table 1
Cross-Cultural Prevalence of Postpartum Blues
Percentage of Women
Country with Postpartum Blues
England 43–76%
France 30%
Germany 41%
Italy 30%
Jamaica 46–60%
Japan 13–26%
Tanzania 50–76%
USA 42–76%
Kumar, 1994; Rondón, 2003
Postpartum depression occurs in 5%–15% of all postpartum women worldwide with relative consistency in China, Japan, the United States, Canada, Europe, Great Britain, Israel and Turkey, and the occurrence of postpartum psychosis is also similar across most cultures (Gale, 2003). Table 2 provides a summary of cross-cultural prevalence rates of postpartum depression.
Table 2
Cross-Cultural Prevalence of Postpartum Depression
Percentage of Women
Country with Postpartum Depression
Arabic women 15.6%
Chile 9%
England 10–23%
Goan women of India 23%
Japan 3–17%
Malaysia 25–35%
Netherlands 20%
Nigeria 10–14.6%
South Africa 34.7%
Uganda 10%
USA 8–26%
Zimbabwe 16%
Adewuya et al., 2005; Keng, 2005; Kumar, 1994
No significant cultural differences have been found in the symptoms of postpartum blues (Rondón, 2003). Symptoms experienced by women with postpartum depression are also similar among different cultures (Adewuya et al., 2005). Among Japanese women, for example, symptoms include depression, tearfulness, tension, irritability, confusion, restlessness, loss of appetite, and poor concentration (Rondón). Brazilian women experienced oversensitivity, over emotionality, tearfulness, lability of mood, and irritation (Rondón). While not much difference has been documented in terms of the symptoms of postpartum blues and postpartum depression, there does appear to be a cross-cultural difference with respect to postpartum psychosis. In Western cultures, there is a high prevalence of affective disturbance in postpartum psychosis. However, in other cultures there is a high rate of schizophrenia, ranging from 44%–75.5% (Kirpinar, Coskun, & Çayköylü, 1999). For example, in a study conducted of Indian women with postpartum psychosis, schizophrenia was more common than depression (Agrawal et al., 1997). In addition, a study conducted in Turkey also showed a much higher rate of schizophrenia in postpartum psychotic women (Kirpinar et al.). This also appears to be the case in Japan and Nigeria (Kirpinar et al.).
Risk factors for postpartum disorders in other countries are not well studied at this time. One study of Nigerian women suggests that the psychosocial risk factors may be somewhat different from those in Western cultures. There did not appear to be any connection to age, marital status, or socioeconomic status for women who suffered from postpartum depression (Fatoye, Adeyemi, & Oladimeji, 2004). One element in the study that did correlate with factors present in Western societies was primiparity (Fatoye et al.).
Neonaticide, Infanticide, and Filicide
Undoubtedly, the most disturbing outcome of postpartum disorders is the occurrence of a woman killing her child. Women suffering from postpartum mental illness are at serious risk for committing such an act (Clayton, 2004). There are five main categories of reasons women kill their children, including: neonaticide, usually involving unwanted pregnancies in young women; in conjunction with a violent or abusive partner; neglect; abuse; and infanticide related to mental illness (Oberman, 2003; Spinelli, 2004). For the most part, mothers who kill their children fall into this last category. Women do not generally kill their children in a “cold-hearted or calculating manner,” rather it is often a consequence of severe depression or psychosis (Gold, 2001, p. 346) and a diminished connection to reality (Chandra, Vankatasubramanian, & Thomas, 2002). Child killings are often “impulsive, unplanned acts emerging from high degrees of stress, frustration, anger, or depression or some combination thereof” (Chandra et al., p. 458). The most common types of child killing include infanticide and filicide (Haapasalo & Petäjä, 1999), with a higher prevalence rate found of the former (Gold). In a study conducted of fifty women with severe postpartum mental illness, 43% had infanticidal ideas, 36% had infanticidal behavior, and 34% had infanticidal ideas and behavior (Chandra et al.). One infant within the first year of life is killed every day in the United States, although some suggest infanticides are underreported and may actually be twice this number (Overpeck, 2003; Spinelli). Maternal filicide rates may also be underreported with up to 20% of cases of Sudden Infant Death Syndrome (SIDS) actually being deaths resulting from filicide (Haapasalo & Petäjä; Overpeck).
Depression is often the most prominent affective feature found in women who commit infanticide and filicide, and is the most common cause of filicide (Chandra et al., 2002). In a review of one study, 25% of the women committed to a psychiatric hospital after killing their children were found to have depression (Chandra et al.). One of the features found more frequently in postpartum depression as opposed to depression occurring at other times is disturbing, aggressive, and obsessive thoughts (Chandra et al.), making the woman a danger to herself and her child. Depressive murder is often linked to the belief that it is in the best interest of the child because the mother does not want her child to be motherless after she commits suicide. This is referred to as “delusional altruism” (Chandra et al., p. 461). The greatest predictor of infanticidal behavior, and the second most common cause of filicide, according to two studies, is psychosis (Chandra et al.; Haapasalo & Petäjä, 1999). A review of women committed to a psychiatric hospital after killing their children found a 40% prevalence rate for psychosis (Chandra et al.).
Despite the known connection between severe postpartum mental illness with infanticide and filicide, women who commit these acts are treated inconsistently in the U.S. legal system, whereas many other countries take into consideration a woman’s mental condition if the killing occurs within one year of giving birth (Manchester, 2003). In 1647, Russia was the first country to “adopt a more humane attitude” (Spinelli, 2004, p. 1550) toward women who committed infanticide. By 1888, most European countries had made a legal distinction between infanticide and murder if the mother was mentally ill (Spinelli). Early in the twentieth century, England enacted the Infanticide Act of 1922, automatically reducing a woman’s sentence from murder to manslaughter and mandating treatment rather than incarceration if the killing occurred within the first year after giving birth (Charatan & Eaton, 2002; Connell, 2002; Manchester). At least 22 other countries around the world have adopted a similar law (Oberman, 2003). In contrast, there is tremendous societal ambivalence in the United States towards women who kill their children, which is reflected by the inconsistent and wide-ranging sentences handed down to them, from prison to the death penalty (Manchester; Oberman; Spinelli).
Discussion, Conclusions, and Recommendations
Women are particularly susceptible to experiencing mental illness following childbirth. These conditions, collectively known as postpartum disorders, include the blues, depression, and psychosis. Postpartum blues is transitory by nature and not particularly alarming, except that worsening symptoms can escalate to postpartum depression. Postpartum depression is similar to depression occurring at other times, although there are distinguishing characteristics, not the least of which is the specific onset of depression triggered by pregnancy and delivery. Postpartum psychosis, the most serious of the postpartum disorders, includes many elements that appear to be unique to psychosis occurring in the puerperium, including psychotic symptoms experienced with greater intensity and frequency, and symptoms that are more unusual.
The risk factors for development of postpartum disorders are many. Psychosocial risk factors include life stressors and sleep deprivation. Low economic status appears to be especially conducive to the development of postpartum depression while primiparity and a history of bipolar disorder are likely contributors to the onset of postpartum psychosis. The results of many family studies show a genetic link for the development of postpartum disorders, particularly when mental illness or a history of postpartum illness is found in first-degree relatives. Other biological factors examined for the part they play in the development of postpartum disorders include the effect of rapidly changing hormones and thyroid dysfunction following delivery.
Many societies around the world recognize the existence of postpartum disorders. Differences exist with respect to psychosocial risk factors as well as presenting symptoms. Nevertheless, many societies acknowledge and study these disorders regardless of cultural differences. Additional scientific research is needed to further identify and classify presenting symptoms and risk factors in other societies.
Fortunately, the killing of a child by its mother is a rare event. However, women afflicted by postpartum depression and psychosis are more at risk for committing such an act. Without question, the threat a mentally ill mother may pose to herself or her child must be taken seriously. While other countries recognize postpartum disorders as legitimate conditions that may cause women to commit infanticide or filicide, the United States has not been as comfortable making it a viable defense.
Enough documentation exists to support the legitimization of postpartum disorders as discrete mental illnesses. Historically and culturally, a woman’s susceptibility to mental illness following childbirth has been acknowledged, yet the psychiatric community in the United States continues to debate whether or not postpartum disorders are distinct from mental illnesses occurring at other times. By failing to come to a positive consensus about the idiosyncratic qualities present in postpartum disorders, a disservice to women and the mental health community is perpetuated. Lack of clearly defined criteria by which postpartum illnesses can be recognized and diagnosed has inhibited research as well as training in the medical community. At-risk women are therefore not always adequately treated, and certainly preventive measures are not taken.
It would be prudent for the psychiatric and medical communities to categorize postpartum disorders as discrete diagnoses. Doing so can only have a positive impact on society. Standardized diagnostic criteria will assist researchers so that the nature of these disorders can be better understood. Greater understanding will in turn promote the development of effective tools for recognizing and treating postpartum mental illness. Additionally, legitimizing the diagnosis of postpartum mental illness will go far with respect to treating women with fairness and dignity in the legal system when the disorder triggers infanticidal acts. Most important, however, is the possibility of saving lives. Some women are pushed to the brink of committing suicide or infanticide when suffering from postpartum disorders. These women deserve recognition and treatment to hopefully prevent tragedies from occurring, like the killing of Andrea Yates’ children. These types of events devastate families and entire communities, certainly making postpartum disorders worthy of their own diagnostic criteria.
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