Researchers at the University of Calgary have identified a few controllable factors that could potentially reduce the rate of sudden infant death syndrome, or SIDS, in Canada.

The study found that prenatal smoking and overheating can contribute to the mysterious phenomenon, which causes the deaths of approximately 200 infants in Canada each year. The root cause of SIDS remains unclear, but the findings from the University of Calgary could save dozens of babies' lives every year.

"SIDS is a diagnosis of exclusion," Dr. Shabih Hasan, the lead author of the study, told CTV Calgary. "We can't say what causes it but we know what factors are associated with it."

Hasan says parents and caregivers should refrain from loading up a child's crib with too many blankets and heavy pieces of clothing, so the child's heartrate does not become elevated from the heat. He also insists babies should always be put to bed on their backs.

"For every single sleep – daytime, nighttime, doesn't matter – the baby should be put on his or her back," Hasan said. "Never on (his or her) stomach or prone position." He added that a single blanket is often enough to keep a child warm, and that the head should not be covered.

The rate of SIDS has fallen significantly since the 1980s, when children were dying of the phenomenon at twice the current rate. The "Back to Sleep" campaign has been credited with helping to reduce those numbers, by encouraging parents to put children back to sleep on their backs whenever they wake up and move around their crib.

Doctors like Hasan insist that the SIDS rate can drop even further, if parents keep a few simple measures in mind.

  1. Don't smoke while pregnant
  2. Don't bundle up a child in too many blankets or clothing
  3. Only put a child to bed on his or her back
  4. Don't overload a child's crib with soft bedding or toys

Breastfeeding the child is also preferable, and parents are advised not to sleep in the same bed as a child, to avoid the danger of smothering.

Hasan and his team developed their findings by studying two groups of pregnant lab rats that were exposed to high heat, infectious bacteria and, in one group's case, second-hand smoke. Researchers found that the offspring of those pregnant rats had greater difficulty with fighting infections. The babies of rats exposed to smoke were also more likely to experience breathing problems, which included a sudden stop in breathing often noticed in SIDS victims.

Sarah Cormier, whose four-month-old child died of SIDS, says parents need to take Hasan's recommendations seriously.

"We want people to know that SIDS still exists – that it happens," she told CTV Calgary. Cormier insists she did "everything right" with her child, but the mysterious affliction still cost the little girl her life.

"It was actually our family dog who alerted us that something was wrong – (it) just started circling the basinet," Cormier recalled. "Your life is forever changed in that moment."

With files from CTV National News Alberta Bureau Chief Janet Dirks and CTV Calgary's Bill MacFarlane.