Along London's Southbank passers by were met with the unusual sight of 'pregnant' mums back-flipping their bumps.
The dancers in the video above weren't really pregnant; they were professionals wearing pregnancy suits. But the idea was to say to people: "Dancing like this when you're pregnant is dangerous. But for mums in poor countries - who often give birth without access to midwives, hospitals, or medicines - pregnancy is an even bigger gamble."
The Millennium Development Goal 5 pledged to reduce the number of women dying in pregnancy or childbirth by 75 per cent, but it is the Goal most off track. World leaders must ensure that the promises they made are put back on track.
Similar flashmobs also went on in Paris, Berlin, Utrecht and Canada, which you can see by browsing over to YouTube.