Postpartum depression is not simply something that happens shortly after birth and then goes away — a new, longitudinal, population cohort study found that depressive symptoms can present and persist several years out from the immediate postpartum period.
In their study, published in Pediatrics, researchers Diane L. Putnick, PhD, from the Epidemiology Branch of the Division of Intramural Population Health Research, at the Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, Maryland, and colleagues looked at four depression trajectories.
“Like other studies, we found a large low-stable group and a small persistently depressed group,” Putnick and colleagues wrote. “In addition, we found 2 other groups of mothers with initially low-level but increasing symptoms and initially medium-level but decreasing symptoms. Approximately one-quarter of women were assigned to groups with elevated symptoms at some point in the 3 years after birth.”
These findings, the researchers noted, have clinical importance for “identifying mothers at risk for persistent symptomatology… Elevated symptoms can last for years after birth, and at least 2 assessments separated by at least several months are needed to determine the trajectory of an individual mother’s symptoms.”
The study authors noted that the American Academy of Pediatrics recommends “that primary care pediatricians screen for maternal depression at children’s 1-, 2-, 4-, and 6-month well visits.” Once the purview of mental health providers and obstetricians, the AAP noted that when mothers are depressed it can increase their child’s risk of cognitive, emotional, and behavioral problems; thus, treating the mother’s symptoms helps to improve child outcomes.
For the study, 5,034 mothers were recruited for Upstate KIDS, which is a population-based birth cohort study. They assessed depressive symptoms at 4 waves — 4, 12, 24, and 36 months — after the mothers gave birth. They also obtained demographic and perinatal conditions from vital records and maternal reports.
There were 1,498 mothers who had undergone some form of infertility treatment and 1,129 who had multiple births. The study cohort included 4,866 or 97% of those recruited who had provided at least 1 depressive symptom assessment. However, 30% of the 4,866 mothers completed all four waves of the assessment and 71% completed two or more waves.
The study authors identified 4 depression trajectories:
- Low-Stable: n=3,637; 74.7%; Mothers in this group started with low symptoms and remained low through all the waves assessed.
- Low-increasing: n=398; 8.2%; These mothers began with some depression at 4 months ,but it increased across all waves.
- Medium-decreasing: n=613; 12.6%; These mothers experienced higher depressive symptoms but the symptoms abated over time.
- High-persistent: n=218; 4.5%; Mothers in this group experienced the highest levels of depressive symptoms at 4 months. The symptoms decreased across all waves but were higher than the other groups through 36 months.
Among their findings, Putnick and colleagues noted that “mothers with a history of mood disorder diagnosis were >3 times as likely to belong to the medium-decreasing group (odds ratio [OR]: 3.67), 4 times as likely to belong to the low-increasing group (OR: 4.12) and 15 times as likely to belong to the high-persistent group (OR: 15.38),” compared with the low-stable group. The mothers whose trajectory was deemed high-persistent also differed from the low-stable group in that they tended to be younger, have less college education, were unmarried, multiracial or a person of color, multiparous, have had gestational diabetes mellitus (GDM), and delivered earlier.
Also of note, mothers who smoked or those who were nulliparous were most likely to be in the medium-decreasing group than in the low-stable trajectory group.
So, what are the risk factors that might predict a mother’s postpartum trajectory? “Older mothers (ORs: 1.08–1.10) and mothers with a college education (ORs: 2.29–2.52) were more likely, and mothers with a mood disorder (ORs: 0.07–0.27) or GDM diagnosis (ORs: 0.23–0.44) were less likely to be classified in any other depressive symptom group than the high-persistent group,” the study authors wrote. “In addition, compared with the high-persistent group, mothers who smoked during pregnancy were more likely to be in the medium decreasing group, and mothers who were nulliparous were more likely to be in the low-increasing group.”
They also noted that they found, in a follow-up analysis, that “having any number of previous live births increased the risk of being in the high-persistent symptom group compared with the low-stable group.”
The study authors did not find a differential association between the trajectories and infertility treatment, multiple births, pre-pregnancy BMI, gestational hypertension, or infant sex.
Putnick and colleagues reiterated that it is important for pediatricians to pay attention to mothers who may be at risk for postpartum depression — those with a history of mood disorder, young mothers, those who didn’t go to college, and those who had GDM.
Limitations of the study, the authors noted, included its design, which required the measurement of depressive symptoms, not clinical depression. “It is possible that longer and more clinical measures of depression might produce different trajectory groups and predictors of those groups,” they wrote. Moreover, most of the study population was non-Hispanic white and data were not collected before 4 months postpartum. Also, the mothers who joined the study may have had fewer depressive symptoms than those found in the general population. Lastly, the study authors noted that they did not know if some women were treated for depression, which might have altered their trajectories.
Symptoms of depression can present — and, for some, persist — well beyond the postpartum period, and approximately one-quarter of women will have elevated depressive symptoms at some point in the three years after birth, study authors found.
Pediatricians should be aware of this as a mother’s depression can increase a child’s risk for cognitive, emotional, and behavioral issues.
Candace Hoffmann, Managing Editor, BreakingMED™
Putnick and colleagues did not disclose any relevant relationships.
Cat ID: 191
Topic ID: 83,191,191,41,192,55,921,925