How effective is postpartum depression screening?
More than one in 10 new mothers is thought to experience significant postpartum depression. The condition has a substantial impact on the whole family, and while effective treatments are available, fewer than half of cases are detected in routine care.
Postpartum depression is typically diagnosed a month to a year after childbirth. Women experience a combination of low mood, fatigue, anxiety, irritability, feelings of being unable to cope and difficulty sleeping. It is distinct from the “baby blues,” which is a short-lasting state of low mood suffered by up to 80 percent of mothers within three to four days following birth.
Postpartum depression is not recognized by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) as being diagnostically distinct from major depression, although the manual does contain a “Postpartum Onset” specifier for patients with an onset within four weeks of giving birth.
Formal screening in the U.S. is often carried out using the Edinburgh Postnatal Depression Scale, a 10-item, self-rated instrument also used throughout Europe, New Zealand and Australia. A threshold score of 12.5 was shown in one Australian study to accurately detect major depression. It can be quickly scored, and a woman who meets a threshold score can be assessed in more detail.
Dr. Mike Paulden of the University of York, UK, and colleagues recently investigated the utility of the Edinburgh Postnatal Depression Scale for widespread screening of new mothers. They write on the website of the British Medical Journal that widespread screening via questionnaire “has been advocated but is controversial.”
Universal screening needs to be balanced against a high rate of false positives, that is, women with an incorrect diagnosis of depression. Although the Edinburgh Postnatal Depression Scale is the most frequently researched, and “performs reasonably well,” the team concludes that it “does not represent value for money for the National Health Service.”
Nevertheless, a worrying number of women with postpartum depression are overlooked in primary care clinics. Victoria Hendrick, associate professor at the University of California at Los Angeles, writes, “The mother’s suffering, coupled with the burden that her depression places on the family and the potential detrimental impact on the relationship between mother and child and the child’s cognitive and social development, call for prompt and effective methods of screening for postpartum depression.”
She adds, “Postpartum depression is a highly treatable condition. A variety of interventions, including antidepressants and psychotherapy, can be helpful. A principal challenge remains in more effectively screening for and identifying this common diagnosis.”
In a study of 214 women who brought their children to a general pediatric clinic, 86 (40 percent) reported high levels of depressive symptoms on the psychiatric symptom index. But only 29 of this group were identified as depressed on a questionnaire given by the pediatricians.
The researchers, from Case Western Reserve University in Cleveland conclude that pediatric health care providers did not recognize most mothers with high levels of self-reported depressive symptoms. They suggest that pediatricians may benefit from extra training, and asking directly about maternal wellbeing or using a structured screening tool to identify mothers who are at risk.
Postpartum depression risk factors include history of depression, abuse, or mental illness, smoking or alcohol use, fears over child care, anxiety before or during pregnancy, background stress, poor marital relationship, lack of financial resources, the infant’s temperament or health problems such as colic, and lack of social support.
C. Neill Epperson, MD, of Yale University School of Medicine, points out that when the onset of postpartum depression is abrupt and symptoms are severe, women are more likely to seek help early in the illness. In cases with a gradual onset, treatment is often delayed, if it is ever sought.
Detecting the condition is often complicated by several factors, he adds. For example, most women expect a period of adjustment after having a baby and may not recognize that what they are experiencing is not within the norm. Women may also be reluctant to admit that something is wrong, out of shame and fear. In addition, women may worry that they will be “locked up” or their baby taken away.
“Another complicating factor is that women who did not receive their perinatal care from a family physician are often confused about whom to turn to,” says Dr Epperson. “To overcome these significant impediments to the identification of postpartum depression, family physicians should develop formal mechanisms for identifying symptoms.”
When a new mother appears to be depressed, he suggests that health care providers “conduct a careful history and physical assessment,” consider her circumstances, and then use a reliable screening questionnaire.
Hendrick, V. Treatment of postnatal depression. The British Medical Journal, Vol. 327, November 1, 2003, pp. 1003-1004.
Paulden, M. et al. Screening for postnatal depression in primary care: cost effectiveness analysis. The British Medical Journal, 2010;340:b5203.
Heneghan, A. M. et al. Do pediatricians recognize mothers with depressive symptoms? Pediatrics, Vol. 106, December 2000, pp. 1367-73.