New research reveals how many calories pregnancy burns – and surprising way energy used

New research has left people shocked at the number of calories pregnancy burns.

Biologists from Monash University in Melbourne have discovered human pregnancy requires an astonishing 49,753 dietary calories. That's the same as 104 McDonald's Happy Meals or 218 Mars bars.

"Most of (the) energy that mammals put into reproduction is 'boiled off' as metabolic heat, only 10% ends up in the actual baby," explained Dr Dustin Marshall, one of the study's authors, in an interview with CNN.

He added: "When both lactation and metabolic loads are accounted for, the baby itself represents less than 1/20th of the total reproductive investment."

The research team looked at data from 81 species – from planktons to humans – to model the energetic dynamics of pregnancy. While most creatures channel about 10% of their energy expenditure into their offspring, humans allocate a mere 4%.

A staggering 96% of the energy is poured into the demanding processes of 'gestation' – the journey from conception to the moment of birth.

"The results were surprising," Dr Samuel Ginther, the study's lead author, said. "We found that for many animals, the energy spent on simply carrying and caring for offspring before birth far outweighs the energy invested in the offspring themselves."

The findings have sparked astonishment across social media platforms, too – but not everyone is surprised. On Instagram, one user said: "I think this is a reminder to men why women deserve comfort and not be at work while pregnant or at all," while another added their voice saying: "I mean OK that's a lot of ice cream to eat in nine months."

Another Instagrammer remarked: "Literally we been saying this...but apparently everyone likes to think that women are 'exaggerating and being hysterical' whenever we talk about this."

Echoing the sentiment, someone else noted: "Us moms could've told you that."