TORONTO -- Two out of three young mothers have at least one mental health problem, according to a new study that also found they faced these issues four times as often as mothers older than 21 and teenagers without children.

The new research, published Feb. 10 in the Journal of Adolescent Health, also found that 40 per cent of young mothers have more than one mental health issue, including depression, some form of anxiety or hyperactivity.

"Young mothers can face a great deal of adversity both before and after becoming a parent,” lead author Dr. Ryan Van Lieshout said in a press release. “Yet next-to-nothing has been known about the rates and types of significant mental health problems among these women in our community."

The authors of the study said identifying and treating these issues in mothers is critical as their mental health affects the wellbeing of their children. Researchers also deemed these parents to be a “high-risk group.”

The hope is the study “can be used to develop better screening processes, more effectively detect mental health problems in teenaged mothers, and direct treatment,” Van Lieshout said.

"We did this study to better understand these problems so that we can help to improve outcomes for young mothers and their families."

Van Lieshout, an associate professor of psychiatry and behavioural neurosciences at McMaster University, also urges for greater partnerships between health-care, educational, and social service organizations to tackle the issue.

The findings, compiled in part with the McMaster Children’s Hospital and funded by Hamilton Health Sciences, stemmed from responses of hundreds of participants of the Young Mothers Health Study between 2012 and 2015.

The researchers recruited 450 mothers in and around Hamilton aged younger than 21 years old, and 100 mothers aged older than 20 years old at the time of their first delivery.

These parents were compared with 15- to 17-year-old girls without children who were assessed for mental disorders via the 2014 Ontario Child Health Study.

This authors claimed the study was the first of its kind to use diagnostic interviews to examine a range of mental health problems beyond postpartum depression. Previous studies were only based on small sample sizes and mailed questionnaires.

"Structured diagnostic interviews are the gold standard for this kind of research,” Van Lieshout said. “We're glad to have used this method to talk to hundreds of young mothers about their experiences."