Children who experience extreme weather events before they're born have lower IQs than those that don't, a new report suggests.
The report from Global Health Alliance Australia laid bare the impacts climate change is having on health, AAP reports.
It looked at more than 100 pieces of research and policy analysis to work out how environmental conditions are affecting people's health.
Global Health Alliance Australia executive director Misha Coleman was shocked by fact the research suggested an effect on children's IQ.
Studies on the subject found evidence the change is due to stress hormones from the mother crossing into the placenta.
One study found specific effects in children that went through the 2011 Brisbane floods, which was part of a cluster of floods in Queensland from 2010 to 2011.
"It's been estimated that those kids lost about 14 IQ points because of the stress their mothers went through," Coleman told AAP.
The study also revealed higher temperatures and greenhouse gasses are leading to increased asthma attacks and allergies.
Coleman said sometimes it could be hard for people to understand the broader implications of climate change on health.
"During the Black Saturday fires for example, people know about how many people died in the fires," she told AAP.
"But over those days, we had like 43 degree temperatures, there were an additional 374 deaths from heatstroke, because there is a relationship with heart failure and other sorts of underlying diseases that are massively exacerbated."