Postpartum Depression

Abstract

After completing this article, readers should be able to: Postpartum depression (PPD) is a significant public health problem, each year affecting 10% to 20% of new mothers. Many of these women and their children experience short- and long-term adverse consequences. Despite an increasing awareness of the effects of maternal depression on children’s health and welfare, it remains unrecognized and poorly understood by women and clinicians alike. Because pediatricians encounter mothers repeatedly during the postpartum year, it is important that they recognize PPD and appropriately educate and refer mothers for evaluation and treatment.PPD describes a heterogeneous group of depressive symptoms and syndromes that occurs during the first year following birth. The American Psychiatric Association Diagnostic and Statistical Manual of Mental Health Disorders-IV (DSM IV) uses the term “postpartum” more specifically to describe symptoms of major depressive disorder, bipolar disorder, or brief psychotic disorder beginning within 4 weeks of delivery. The psychiatric postpartum experiences usually are divided into three categories: “maternal blues,” PPD, and postpartum psychosis. The DSM IV does not apply “postpartum” to other psychiatric illnesses. However, anxiety disorders, such as panic, obsessive-compulsive disorder, and phobias, can have an initial onset or exacerbation in the postpartum period.Maternal blues or postpartum mood reactivity is considered a “normal” emotional experience for women in the immediate postpartum period. It is estimated that 50% to 80% of new mothers experience transient symptoms of depressed mood, at times alternating with elated moods, irritability, increased crying spells, and a sense of “unreality” during the first 10 days after birth. These symptoms usually resolve without intervention. On the other end of the spectrum is postpartum psychosis, a rare (1/1,000 live births) and serious event that generally occurs within 2 weeks of delivery and is considered a psychiatric emergency that requires immediate psychiatric intervention. PPD falls in the middle, occurring in 10% to 20% of postpartum women and presenting with a range of mild to severe depressive symptoms.Almost 50% of PPD cases are continuations of depressive episodes that occur during or before pregnancy. The incidence of new-onset cases of depression during the postpartum year is estimated to be 15%. However, new-onset cases occur throughout the year; the peak prevalence is at 10 to 14 weeks after delivery.Little is known or understood about the natural course of PPD. In the general population, the average length of a depressive episode is approximately 5 months. In PPD, the natural course and length of time until remission are unknown. Some studies indicate that postpartum episodes resolve more quickly than episodes in the general population; other studies report episodes of similar duration.Risk factors for developing PPD continue to be studied. Currently, the following have been found to increase a woman’s risk: younger maternal age, lower education, single marital status, lower socioeconomic status, personal or family history of a mood disorder, depression during pregnancy, psychosocial stress, lack of social support, and marital discord. Women who have a history of a mood disorder have twice the risk of women in the general population (10% to 40%) of experiencing PPD. Women who have bipolar disorder have the highest risk of developing a postpartum episode, whether psychosis, mania, or depression.The exact pathogenesis of PPD is unknown. It generally is believed that maternal blues is related to the hormonal and physiologic changes that occur after delivery. The role of the dramatic biologic and hormonal fluctuations in the postpartum period is under investigation, with current theories centering on the rapid decrease in progesterone, estradiol, and estriol. Other researchers are exploring the role of the hypothalamic-pituitary-thyroid axis and thyroid dysfunction in PPD. Another biologic theory, related to cyclical hormonal changes, is the kindling model. Because many women who have PPD also experience other reproductive-related mood disorders (premenstrual dysphoric disorder, perimenopausal mood disorders), the kindling model hypothesizes that each reproductive-related psychiatric episode sensitizes the woman to the development or exacerbation of another episode. Psychosocial factors, including culture, social support networks, and economic pressures, also can affect life and role transitions such as motherhood and, hence, are hypothesized to contribute to the development of PPD in some women.It is important to recognize the range of severity and symptomatology that mothers who have PPD can experience. PPD often is differentiated into major and minor depression. Most women (70%) experience minor depression. Symptoms of PPD may include the full range of emotional, cognitive, and neurovegetative symptoms of depression (Table 1). Women who have PPD often experience a cognitive dissonance between being glad they have new infants and not being able to enjoy their children. They may experience anxiety and obsessional thinking that is focused on the welfare of the child and concerns about their parenting ability. Despite what can be severe symptomatology, many women and clinicians do not identify these symptoms as depression.Expert opinions differ as to whether PPD symptoms are unique or “atypical” compared with symptoms of depression in the general population. Some studies indicate that women who have PPD report higher levels of somatic complaints and more irritability, anxiety, fatigue, and depression than women who have depression not related to childbearing. Other studies have found no difference in symptomatology between the two groups.Untreated PPD may result in poor outcomes for the health and welfare of both women and children. There is substantial evidence that maternal depression can have a negative impact on the cognitive, social, and behavioral development of children, including infants and toddlers (Table 2). Although there is no agreed-upon “high-risk age” for exposure to maternal depression, there is evidence that even very young infants exposed to depressed mothers can exhibit withdrawn behavioral styles as early as 3 months of age.The effects of maternal depression can be severe and long-lasting. Infants of depressed mothers may be at increased risk of child abuse and are more likely to exhibit insecure attachment patterns. The behaviors that may be exhibited when attachment is impaired are listed in Table 2. Early attachment patterns are important because they remain stable and influence relationships later in a person’s life. School-age children who had postnatally depressed mothers have increased rates of behavioral disturbance. In addition, recent studies have identified that maternal depression may affect the mother’s implementation of and follow-through with pediatric preventive practices as well as the use of pediatric health care services. Adult offspring of depressed parents have increased rates of major depression as well as other psychiatric disorders. Finally, it is important to remember that not all children of depressed mothers experience these outcomes; many children cope effectively and develop normally.Many factors contribute to the effects of PPD on infant development. The severity and duration of the condition as well as the stress of life events, maternal age, number of children, economic resources, and emotional support can influence maternal behavior and its subsequent impact on infant development. Furthermore, maternal depression can affect parenting behavior, parenting attitudes, maternal-infant interactions (Table 3), family dynamics, and marital harmony/discord in a variety of ways. An important example of the heterogeneous nature of PPD and its effects are the parenting behaviors exhibited by depressed mothers. Depressed mothers may exhibit normal behavior and affect, be withdrawn and disengaged, be angry and intrusive, or manifest a combination of these behaviors. Infant responses depend on the mother’s behavior. Infants of withdrawn mothers are more likely to exhibit fussy and crying behavior; infants of angry mothers avoid looking at or interacting with their mothers. The child’s temperament, behavior, and concomitant medical complications also can affect the severity of maternal depression and the mother’s ability to cope and parent effectively. The child’s biologic and genetic predisposition as well as the age may influence the child’s responses to maternal depression.Mothers also may suffer negative repercussions from the PPD experience. They are at higher risk of future depression, not just recurrent PPD. Studies of adolescent mothers find that at 4 months postpartum, depressed adolescent mothers are three times more likely to use alcohol or illicit substances than are nondepressed adolescent mothers. Mothers may have difficulty attaining a healthy maternal role and confidence in their parenting skills. Studies have found that women change their reproductive plans and may choose not to become pregnant again to avoid another postpartum episode.Interpersonal psychotherapy, cognitive behavioral therapy, and antidepressants have been successful in treating PPD. Support groups and psychoeducational material also are essential to decrease the isolation of affected women and to increase their understanding of the disorder and their options for help.Because women who have PPD often do not recognize their symptoms as depression, most do not seek professional care. Almost 50% of women who have clinically significant symptoms of PPD remain undetected by clinicians. Except for the 1-month obstetric postpartum visit, healthy childbearing women do not see a health care practitioner regularly, except pediatricians, during the postpartum year. Thus, pediatricians have a unique opportunity to assess women and to provide early intervention, education, and appropriate referral.Although most pediatricians will not treat mothers, screening mothers for psychosocial issues that may affect children and families is within their scope of practice. Some pediatricians informally screen for maternal depression, but a recent study found this method to be inadequate (Heneghan, et al, 2000). Researchers screened mothers of infants and toddlers for depression with a validated screening tool. At the same time, pediatric clinicians completed questionnaires about the mother that included 10 depressive symptom items. A comparison of results showed that pediatric clinicians did not recognize most mothers who had depressive symptoms regardless of symptom severity.The first step to improving detection is to educate pediatricians about the prevalence, risk factors, and symptoms of PPD. With heightened awareness, pediatricians may be more likely to ask psychosocially oriented questions about the mother and family functioning. Table 4 provides a partial list of questions to help pediatricians begin to talk with mothers about this important, often hidden issue. No studies to date have established an improved rate of PPD detection with the use of these specific questions. Another possibility is to use a validated screening tool. The advantages of a screening tool are that it is quick and easy and has been validated to detect depression at a specific score. Thus, pediatricians may feel more confident talking with mothers about their feelings with this information in hand. Studies in Britain and Sweden indicate that it is feasible for pediatricians to screen mothers for PPD during health supervision visits. Logically, the next questions are: “What screening tool do I use and when?”Only three depression screening tools are designed and validated specifically to detect PPD effectively: The Edinburgh Postnatal Depression Scale (EPDS) (Cox et al, 1987), Postpartum Checklist (Beck, 1995), and the Postpartum Depression Screening Scale (PDSS) (Beck and Gable, 2000). Scales developed to screen for depression in the general population may not detect PPD as well because of the overlap of somatic symptoms (sleep disturbance, fatigability, loss of appetite, somatic preoccupation, loss of libido, body image) with the physical changes in the postpartum period. The EPDS, Postpartum Checklist, and PDSS were designed to minimize the effects of this overlap in the assessment of depression.Screening should not be implemented without attention to follow-through. Because PPD remains undetected by many clinicians, all mothers should be screened, not just those whom pediatricians feel may be at high risk. The number of times and the visit at which mothers should be screened during the postpartum year have not yet been established. However, with the current knowledge of peak prevalence occurring around 3 months, the incidence of new cases throughout the postpartum year, and the significant long-term effects of PPD on mothers and children, it is reasonable to screen mothers at least three times during the year. The 2-, 6-, and 12-month health supervision visits (as well as any time the pediatrician is concerned about the mother) are reasonable time points to use a brief screening tool.Repeated screens may be used to: 1) track changes in symptom severity to determine the need for referral and intervention, 2) identify women at risk as well as affected women, 3) identify women who have suicidal ideation, 4) provide mothers a nonverbal venue to express their emotions, and 5) provide an opening for discussion of other sensitive issues.The practical implementation of using a screening tool in a busy clinical practice is critical. Clinicians must be careful to use the information rather than simply gather the data. It is essential to score the measure consistently and to pay attention to answers that imply high risk (eg, suicidal ideation). Unless there is imminent danger to the mother or infant, the pediatrician’s role is limited to providing information about PPD and referring the mother to her primary care clinician, a psychiatrist, a therapist, self-help groups, or Web sites of organizations that may provide education and networking sources. Pediatricians also can help the family by monitoring the impact of the depression on the mother-child interaction, the pediatric preventive practices, and the infant’s health and development. Pediatricians already routinely assess preventive practices and infant development. The mother-child interaction may be assessed by a combination of asking questions (“How connected do you feel to your baby?” or “Do you enjoy playing with the baby?”) and closely observing the interactions (Table 3).With knowledge of the mother’s depression, the pediatrician can provide information and support to the mother as she determines her treatment options. One option is antidepressant treatment. Many mothers who have PPD experience guilt and anxiety when deciding whether to take medications while breastfeeding. Many know the benefits of human milk and wish to breastfeed, but are concerned about their infants’ exposure to medication. The pediatrician, in collaboration with the mothers’ psychiatrists, can support women in their choices and assist them in weighing the risks and benefits of using specific medications while breastfeeding. The risk-benefit analysis must be highly individualized, taking into account the severity of the maternal illness, the maternal support system, the age and health of the infant, and the potential effects of either nursing or not on the mother’s self-esteem. Furthermore, the role of sleep deprivation and the potential for an exacerbation of symptoms due to insomnia associated with breastfeeding must be considered. Insomnia is an especially important consideration for women who have bipolar disorder because it may precipitate mania, depression, or even psychosis.Recent articles review the use of psychotropic medications during breastfeeding (Llewellyn and Stowe, 1998; Chaudron and Jefferson, 2000; Ito, 2000; Burt et al, 2001). These articles provide clinicians with comprehensive reviews, including maternal and infant serum levels, human milk levels, and milk-to-plasma ratios of infants exposed to antidepressants and mood stabilizers through human milk. Table 5 summarizes these reports. The review by Ito suggests that tricyclic antidepressants and sertraline are the antidepressants of choice. However, the article does not address the newer antidepressants or other serotonin reuptake inhibitors except fluoxetine. Among the mood stablizers, carbamazepine and valproate generally are recommended because they are estimated to expose infants to less than 10% of the therapeutic dose standardized by weight. In general, lithium is not recommended during nursing. The American Academy of Pediatrics Committee on Drugs Report (2001) classifies lithium as “associated with significant effects on some nursing infants” and recommends its use with caution in nursing mothers because of the potential for toxicity. However, if a mother requires lithium and chooses to nurse, lithium levels should be monitored closely in the mother’s plasma and milk and the infant’s plasma. The infant also should be monitored for any signs of lithium toxicity.PPD is a treatable and underrecognized illness that affects 10% to 20% of new mothers and may have significant repercussions for the health and well-being of women and their children. Pediatricians may help mothers to identify, cope with, and seek treatment for PPD by routinely screening new mothers for depression, identifying high-risk maternal attitudes and behaviors, providing referrals to mental health specialists, and assisting with the risk-benefit analysis of medication treatment during breastfeeding. By becoming actively involved, pediatricians can help their pediatric patients.