Women's Health Matters

Text Size
Jump to body content

Postpartum depression can continue beyond the first few months after giving birth

Oct. 19, 2012

By Patricia Nicholson

New mothers are most often assessed for postpartum depression in the first 12 weeks after giving birth. However, new research shows that for a significant number of women, postpartum depression can last throughout the first year and beyond.

“For some mothers postpartum depression will resolve on its own,” says the study’s lead author, Dr. Cindy-Lee Dennis, senior scientist at Women’s College Research Institute and Shirley Brown Chair in Women’s Mental Health Research at Women’s College Hospital. “However, this research suggests that for about eight per cent of mothers the depression continues and professional treatment is necessary.”

The study, which was recently published in the Canadian Journal of Psychiatry, used data from a national sample of 6,421 women who participated in the Maternity Experiences Survey of the Canadian Perinatal Surveillance System. The participants completed the survey between five and 14 months after giving birth.

In addition to finding that eight per cent of Canadian women had symptoms of depression past 12 weeks postpartum, the study also identified several factors associated with increased risk of postpartum depression. A previous history of depression was associated with an 87 per cent increased risk of postpartum depression, and low household income was associated with a 64 per cent increased risk. Interpersonal violence was linked to a 40 per cent increased risk of postpartum depression. The strongest risk factors were having several stressful life events in the year preceding childbirth, which was associated with an almost 2.5-fold risk of postpartum depression, and low postpartum social support, which almost quadrupled the risk.

“Psychosocial variables are highly significant, even when we adjusted for other covariates, such as parity,” Dr. Dennis says. “Interpersonal violence, a significant number of stressful life events in the year preceding childbirth, low postpartum support and low income – these are all psychosocial variables.”

Dr. Dennis believes that the depression affecting women later in the postpartum period is probably depression that is continuing, rather than postpartum depression that is beginning later. “For the majority of mothers, if they’re going to develop postpartum depression, they usually develop it within the first 12 weeks,” Dr. Dennis says, adding that many women with postpartum depression report their depressive symptoms started within the first four weeks after giving birth.

“So we know postpartum depression often begins early in the postpartum period for many mothers and for about eight per cent of these women their depression will continue past the first year postpartum,” Dr. Dennis explains. “It is also important to note postpartum depression can actually be a continuation of depression that started during the pregnancy which was not detected or treated.”

This information is crucial because of the significant impact a mother’s depression can have on the first year of a child’s life. Because maternal depression affects a mother’s behaviour and cognitions, it also affects the child’s development. Dr. Dennis also suggests maternal depression is a significant risk factor for paternal depression, placing infants and children at even greater risk for poorer developmental trajectories. Approximately 11 per cent of fathers will also experience depression in the first year following childbirth, which can lead to a very stressful home environment for children.

The study results highlight a need for depression screening beyond the first 12 weeks after childbirth.

“We’re very focused on screening mothers early in the postpartum period but this research suggests that we should also be screening mothers later in the postpartum period whenever they have contact with a health professional. For example, a pediatric visit with the baby would be an ideal time to screen,” Dr. Dennis says. “We need to develop notions of identifying depression in mothers later in the postpartum period and past the first year.”

Jump to top page
  • A publication of:
  • Women's College Hospital