The phrase “happy mom, happy baby” has never been more accurate.

Research from the University of Calgary’s faculty of medicine suggests the mood of a pregnant woman can impact her baby’s health.

Gerry Giesbrecht, psychologist and lead author of the study, said the study assessed how the stress hormone cortisol fluctuates when a woman’s mood changes.

“We know that cortisol crossed the placenta and we know that too much cortisol is associated with poor development,” he said. “What our study is showing is we should be paying attention to stress, depression and anxiety during pregnancy because of the way it affects cortisol in pregnant women.”

Fiona McCord took part in the study when she was pregnant with her now nearly two-year-old son, Brik, and will take the results to heart if she has future pregnancies.

“I think any study that says, ‘Don’t do this because it has negative results for your baby,’ you’ll follow.”