Richard Branson
Sir Richard Branson is worth an estimated £5 billion. Reuters

Billionaire Richard Branson has revealed how he had to call an ambulance after losing his virginity when the woman he was having sex with suffered a mid-coitus asthma attack he mistook for evidence of his own sexual prowess.

"I thought I must have been the greatest lover of all time," the Virgin founder said, "because the lady seemed like she was enjoying it until she whispered in my ear 'asthma attack, asthma attack'.

"The ambulance brought me back down to earth with a bump."

Branson, 67, was speaking ahead of the release of his second biography Finding My Virginity. He also discussed the book's title, saying he lost an argument with publishers.

"I think our publishers decided that it would only be sold in Soho backstreet shops so I was talked down of that one. I did a book about flying and I wanted to call that one 'Getting It Up' and they wouldn't let me do that either."

The magnate, who is worth $5 billion (£3.7 billion), recently launched a fundraising appeal for those affected by the devastation left by Hurricane Irma as it tore across the Virgin Islands and Caribbean.

Branson owns his own private island, called Necker Island, in the region.

"As you can see from the photos, much of the buildings and vegetation on Necker has been destroyed or badly damaged," Branson wrote in a blog post from Puerto Rico as he kickstarted efforts to aid an enormous recovery operation.

"We felt the full force of the strongest hurricane ever in the Atlantic Ocean. But we are very fortunate to have a strong cellar built into Necker's Great House and were very lucky all of our teams who stayed on Island during the storm are safe and well."

He has also called on the British government to establish a plan for the recovery of the region, which was torn apart by the category five storm when it struck in early September.