What is postpartum depression?

Postpartum depression is a major depressive episode occurring in the postpartum period.¹ While the United States Centers for Disease Control and Prevention (CDC) and the American College of Obstetricians and Gynecologists (ACOG) define this as the 12 months following childbirth, there is disagreement in the field about the length of this period and thus about the precise definition of postpartum depression.

The American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) does not have a distinct definition for postpartum depression but rather uses peripartum onset as a specifier for major depressive disorder, with the requirement of onset during pregnancy or within the first four weeks postpartum.² DSM-5 notes that depressive episodes can begin prior to delivery, which led to their decision to refer to the condition as major depressive disorder with peripartum onset. However, this broad terminology loses the distinction between depression with prenatal onset and postpartum onset. Genetic and other biological evidence indicates that depression with onset in pregnancy may be biologically distinct from that with onset postpartum, and onset within the first 6-8 weeks postpartum may also be biologically distinct from that arising later in the postpartum year.³

The below diagnostic criteria for a major depressive disorder are pulled directly from DSM-5: ²

1. Five (or more) symptoms of depression in a two-week period that represent a change from previous functioning; at least one of the symptoms is either (1) being depressed mood or (2) loss of interest or pleasure.
   1. Depressed mood most of the day, nearly every day, as indicated by either subjective report (e.g., feels sad, empty, hopeless) or observation made by others (e.g., appears tearful). (Note: In children and adolescents, can be irritable mood.)
   2. Markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly every day (as indicated by either subjective account or observation).
   3. Significant weight loss when not dieting or weight gain (e.g., a change of more than 5% of body weight in a month), or decrease or increase in appetite nearly every day. (Note: In children, consider failure to make expected weight gain.)
   4. Insomnia or hypersomnia nearly every day.
   5. Psychomotor agitation or retardation nearly every day (observable by others, not merely subjective feelings of restlessness or being slowed down).
   6. Fatigue or loss of energy nearly every day.
   7. Feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) nearly every day (not merely self-reproach or guilt about being sick).
   8. Diminished ability to think or concentrate, or indecisiveness, nearly every day (either by subjective account or as observed by others).
   9. Recurrent thoughts of death (not just fear of dying); recurrent suicidal ideation without a specific plan; a specific suicide plan; or a suicide attempt.
2. The symptoms cause clinically significant distress and impairment in social, occupational, or other important areas of functioning.
3. The episode is not attributable to the physiological effects of a substance or another medical condition.
4. At least one major depressive episode is not better explained by schizoaffective disorder and is not superimposed on schizophrenia, schizophreniform disorder, delusional disorder, or other specified and unspecified schizophrenia spectrum and other psychotic disorders.
5. There has never been a manic episode or a hypomanic episode.

While the above criteria apply to any episode of depression, it is likely that there are distinct clinical features to postpartum depression.  One influential study from 2017 found five distinct clinical phenotypes of postpartum depression, three of which included prominent anxiety symptoms.⁴

Postpartum depression is common; a 2018 meta-analysis of 58 studies found that the global prevalence of postpartum depression was 17% (95% Confidence Interval [CI] [0.15-0.20]).⁵ A 2013 study (n=9,998) found that at four and six weeks postpartum, 14.0% of women had depression as assessed by the Edinburgh Postnatal Depression Scale (EPDS; scored from 0-30 with scores of 10 or higher indicating a positive screen for depression).⁶ Minority women were more likely to have postpartum depression, with 19.4% of Black women, 18.9% of Asian women, 18.1% of Hispanic women, and 22.6% of those identifying as other having depression compared to 12.5% of white women. Among the 826 participants who accepted further diagnostic assessment, 40.1% experienced onset of depressive symptoms within four weeks after birth, 33.5% had onset during pregnancy, and 26.5% before pregnancy, meaning that the 14.0% incidence of depression represented a mixture of antenatal and postpartum depression cases.

Postpartum depression is a serious condition that has been associated with a variety of negative health outcomes for both mother (worse psychological health, quality of life, interpersonal relationships, and risk of suicide) and baby (lower weight and length, worse overall health, more disruptive sleep, worse motor development, social-emotional development, and behavioral development).⁷ It’s difficult to know whether these deleterious effects on early childhood development are due to the postpartum depression itself or stem from the bonding and attachment difficulties associated with postpartum depression. While postpartum depression is linked to bonding difficulties, these negative health effects may also be applicable to those without postpartum depression who have bonding and attachment difficulties from other causes.

A population-based study in Canda of women who gave birth between 1988-1992 examined the cause of death for women during pregnancy or in the postpartum period.⁸ Results were divided into two time periods; pregnancy and early postpartum defined as 20 weeks’ gestation to 42 days postpartum and the remainder of the postpartum period defined as 43-225 days postpartum. Suicide was the cause of 2.14% of deaths in the earlier group (n=187) and 17.92% in the later group (n=251), making it a leading cause of death. The other leading causes were circulatory disease (17.64% of earlier deaths, 14.34% of later deaths), cancer (5.88% of earlier deaths, 16.33% of later deaths), and motor vehicle accidents (11.76% of earlier deaths, 20.72% of later deaths).

A CDC report on maternal mortality in 2020 using data from 38 states found 525 cases of deaths during pregnancy or within one year of the end of pregnancy.⁹ The leading causes of death were mental health conditions (22.5%), cardiovascular conditions (16.6%), infection (16.4%), and hemorrhage (11.2%). Mental health conditions included deaths of suicide, overdose/poisoning related to substance use disorder, and other deaths determined to be related to a mental health condition.

ACOG’s 2023 clinical guidelines for perinatal depression (encompassing both antenatal and postpartum) recommend psychotherapy as first-line treatment for mild-to-moderate depression.¹⁰ While ACOG does not have any specific recommendations of therapy modalities to treat postpartum depression, they cite various counseling interventions, primarily cognitive behavioral therapy (CBT) and interpersonal therapy (IPT), as effective at reducing the risk of developing postpartum depression.¹

When pharmacotherapy is needed, ACOG recommends selective serotonin reuptake inhibitors (SSRIs) be used as first-line pharmacotherapy, with serotonin-norepinephrine reuptake inhibitors (SNRIs) as reasonable alternatives.¹⁰ Recent evidence indicates that the risks to the fetus and newborn due to psychiatric drugs, which are low, are usually outweighed by the risks to mother and child of untreated depression.^11,12 Untreated depression carries risk including suicide risk, marital discord, not seeking proper obstetrical care, and difficulty caring for children.

It’s difficult to know how long postpartum depression can last without treatment. One 2020 population-based cohort study (n=4,866) found that the mean number of participants with depressive symptoms (assessed using an abridged 5-item Edinburgh Postnatal Depression Scale [EPDS-5]) remained relatively similar from four months to three years postpartum (2.73% at four months, 2.42% at 12 months, 2.26% at two years, and 2.42% at 3 years).¹³

Postpartum depression is distinct from postpartum blues, colloquially called baby blues.¹² Baby blues does not have a strict definition, but it is a common transient emotional condition that occurs early in the postpartum period. A 2020 systematic review and meta-analysis of 26 studies found that the estimated prevalence varies from 13.7% to 76.0%, with an overall aggregated prevalence of 39.0%.¹⁴ Despite its commonality, its pathophysiology is poorly understood.

Hallmark symptoms can include emotional lability, depressed mood, tearfulness, unstable mood, insomnia, and anxiety.¹² It typically starts very close to birth and ends within two weeks. Symptoms lasting longer than two weeks or severe symptoms such as suicidal ideation are never part of the baby blues but rather an indication of incipient postpartum depression or another illness.

References

1. Screening and Diagnosis of Mental Health Conditions During Pregnancy and Postpartum: ACOG Clinical Practice Guideline No. 4. Obstet Gynecol. Jun 1 2023;141(6):1232-1261. doi:10.1097/aog.0000000000005200
2. Depressive Disorders. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR®). American Psychiatric Association; 2022.
3. McEvoy K, Osborne LM, Nanavati J, Payne JL. Reproductive Affective Disorders: a Review of the Genetic Evidence for Premenstrual Dysphoric Disorder and Postpartum Depression. Curr Psychiatry Rep. Oct 30 2017;19(12):94. doi:10.1007/s11920-017-0852-0
4. Putnam KT, Wilcox M, Robertson-Blackmore E, et al. Clinical phenotypes of perinatal depression and time of symptom onset: analysis of data from an international consortium. Lancet Psychiatry. Jun 2017;4(6):477-485. doi:10.1016/s2215-0366(17)30136-0
5. Shorey S, Chee CYI, Ng ED, Chan YH, Tam WWS, Chong YS. Prevalence and incidence of postpartum depression among healthy mothers: A systematic review and meta-analysis. J Psychiatr Res. Sep 2018;104:235-248. doi:10.1016/j.jpsychires.2018.08.001
6. Wisner KL, Sit DK, McShea MC, et al. Onset timing, thoughts of self-harm, and diagnoses in postpartum women with screen-positive depression findings. JAMA Psychiatry. May 2013;70(5):490-8. doi:10.1001/jamapsychiatry.2013.87
7. Slomian J, Honvo G, Emonts P, Reginster JY, Bruyère O. Consequences of maternal postpartum depression: A systematic review of maternal and infant outcomes. Womens Health (Lond). Jan-Dec 2019;15:1745506519844044. doi:10.1177/1745506519844044
8. Turner LA, Kramer MS, Liu S. Cause-specific mortality during and after pregnancy and the definition of maternal death. Chronic Dis Can. 2002;23(1):31-6.
9. Trost S, Busacker A, Leonard M, et al. Pregnancy-Related Deaths: Data from Maternal Mortality Review Committees in 38 U.S. States, 2020. U.S. Department of Health and Human Services Centers for Disease Control and Prevention; 2024.
10. Treatment and Management of Mental Health Conditions During Pregnancy and Postpartum: ACOG Clinical Practice Guideline No. 5. Obstet Gynecol. Jun 1 2023;141(6):1262-1288. doi:10.1097/aog.0000000000005202
11. Chapter 13. Depressive Disorders. In: Hutner LA, Catapano LA, Nagle-Yang SM, Williams KE, Osborne LM, eds. Textbook of Women's Reproductive Mental Health American Psychiatric Association Publishing; 2022.
12. Osborne LM, Payne JL. Clinical Updates in Women's Health Care: Mood and Anxiety Disorders. The American College of Obstetricians and Gynecologists; 2017.
13. Putnick DL, Sundaram R, Bell EM, et al. Trajectories of Maternal Postpartum Depressive Symptoms. Pediatrics. Nov 2020;146(5)doi:10.1542/peds.2020-0857
14. Rezaie-Keikhaie K, Arbabshastan ME, Rafiemanesh H, Amirshahi M, Ostadkelayeh SM, Arbabisarjou A. Systematic Review and Meta-Analysis of the Prevalence of the Maternity Blues in the Postpartum Period. J Obstet Gynecol Neonatal Nurs. Mar 2020;49(2):127-136. doi:10.1016/j.jogn.2020.01.001