Pictured: The beaming mother of one who is ditching her career to be a professional cage fighter

But despite her beaming smile and slight frame, Dr Sexton has been hiding a secret career that is far removed from her day job as a computer expert.

The 30-year-old, who has a PhD from Cambridge, is a prize-winning cage fighter regularly battling it out in one of the most brutal and bloody sports in the world.

Brutal: Rosi Sexton might look friendly but she is a prize-winning cage fighter

Dr Sexton, from Manchester, has been fighting in the ring for six years after taking it up as a hobby when she started her doctorate.

But she has just signed a big money deal to appear on U.S. television and is ditching her hi-tech career to become a professional fighter full-time.

The sport has a gruesome reputation for bloody, no-holds-barred brawling and pictures of Dr Sexton in action show her pinned to the ground by her opponent.

She decided to take up the sport as a career after a series of spectacular wins.

No-holds-barred: Dr Sexton in the ring

The mix of martial arts used in the ring involves a combination of kickboxing and wrestling, with gruelling bouts lasting up to half an hour.

To keep in top condition and ready for whatever her opponents throw at her, Dr Sexton now trains up to three times a day in her local gym.

Her three-fight deal with a major American broadcaster will see her battle against some of the top female fighters in the U.S.

The matches will be broadcast to millions and earn her thousands of pounds, with the first match set to take place in August.

Fighter... and a mother: Dr Sexton in the gym and right, with her son, Luis

Despite its fearsome reputation, Dr Sexton insists the sport is no longer the highly dangerous activity it once was and is actually very well-regulated.

'I've been pretty lucky. I have had a few minor injuries, such as dislocating my toe,' she says.

"There are risks involved, as there are with any sport, but there is a higher risk with things such as horse racing or rugby.'

'Mixed martial arts is very well-regulated and refereed. There are bumps and bruises, but serious injuries are actually quite rare.

'It is quite a big deal with an American broadcaster and some of the large networks. It means I'll be able to compete against some of the best people in the world.'

Academic: The 30-year-old graduated from Cambridge before doing her doctorate in computer science at Manchester University

Luckily, her new career is also a family affair because her trainer, Karl Tanswell, is also the father of her son, Luis.

And they need not fear that the 30-year-old is planning on it as a profession in the long-term - she is already training to be an osteopath.

With a specialism in sports injuries, her skills could yet come in handy to ease any aches and pains sustained in the ring.

Family affair: Luis and his father Karl Tanswell look on as Dr Sexton fights

Rosi Sexton, who obtained a PhD in computer science from Manchester University