Extreme heat can double stillbirth risk - study

Earth's average temperature is projected to rise by nearly three degrees by the end of the century, compared with pre-industrial times, and the World Health Organization (WHO) is warning of "an existential threat to all of us" with pregnant women facing "some of the gravest consequences".

For the study in India, the researchers used what is called the wet-bulb-globe-temperature (WBGT), which measures the effects of temperature, humidity, wind speed and radiant heat on human bodies.

India is predicted to become one of the first countries in the world where temperatures will top the safe limit for healthy people who are simply resting in the shade, according to a recent study from the University of Cambridge.

She says a previous study found many women didn't want to squat in an open field to relieve themselves and so would avoid drinking water, developing urinary problems as a result.

India has made huge improvements to maternal and baby health in recent years, but the stillbirth rate is still 12.2 per 1,000 births, according to data from the World Bank Group.

On the outskirts of Chennai, Thillai Bhasker - a brick-kiln owner - has erected giant steel roofs with special heat-protective coatings on them, to provide his workers with much-needed shade.