Author Jill Mansell cannot contain her excitement. Her new book Three Amazing Things About You is the most satisfying she has ever written, the critics love it and this Valentine’s Day copies will be flying off the shelves, no doubt.

The queen of romantic comedy fiction has now notched up 26 novels and 10 million sales, with book number 27 (as yet untitled) almost finished. Despite these mind-boggling statistics, she refuses to view herself as a prolific writer. “I only write one book a year,” she says with characteristic modesty. “Other people can write three books a year! But I’m a slow writer, 1,000 words a day is my average. I couldn’t manage two books a year and publishers like consistency, so I stick to the one.”

A former clinical neurophysiologist, Mansell decided to swap her white coat for a typewriter after reading a magazine article about women who had written bestsellers, Jilly Cooper was one of them, as were Mills and Boon authors Charlotte Lamb and Anne Hampson. She would never have dreamt that one day she’d be joining such distinguished company. “I was sitting in the waiting room at the hospital where I worked, picked up a magazine and started reading about four women who had transformed their lives by becoming bestselling authors,” she recalls.

“I thought ‘I’d like to do that’! I then joined a local evening class in creative writing and that was it. These women made becoming a writer seem achievable to me.”

It’s easy to sneer at the fictional genre commonly known as ‘chick lit’ where the hapless heroine eventually meets her handsome hunky Mr Right and lives happily ever after. But it is undeniably a widely read and hugely popular genre and lucrative for those authors who have nailed it.

Mansell knew she wanted to write romantic fiction but not in the traditional, formulaic vein of Barbara Cartland or Mills and Boon. Key to her style from the start was an injection of humour.

“When I first started going to my evening class, all those years ago, the class was taught by a Mills and Boon writer, and at the time you could write 
10 Mills and Boons books a year and become a multimillionaire. So I did try to write for them but they wrote back and rejected what I’d written saying, ‘Too many jokes and too much humour!’”

A snub from a major publisher of romantic fiction could have been a crushing blow to the ambitions of a budding writer but Mansell decided to stick to her romantic comedy leanings and soon afterwards her first book was published, Fast Friends in 1991 through UK publisher Headline Books. She left her job at the hospital in 1992 and hasn’t looked back. “When I wrote my first book I never expected it to be published,” she admits. “A lot of people write one book then can’t write a second. I was so thrilled my first book had been accepted, I found the second really easy to write and just sort of carried on from there.”

Astonishingly, she has written most of her novels by hand because sitting at a keyboard and typing just doesn’t allow the creative juices to flow. “It would be a million times easier if I could just type when writing my books,” she says. “Another writer once said to me, ‘Writing your books by hand is like refusing to use a washing machine and carrying all your washing three miles downhill to a river, and then washing your clothes in the river!’ I’ve tried typing so many times but it just doesn’t flow.

“There are quite a few of us who still write our books by hand – Jackie Collins, Joanna Trollope, Jilly Cooper and Jeffrey Archer all do. And our names all begin with J!”

Fortunately Mansell’s publisher no longer has to type all of the manuscripts – she’s commandeered her 22-year-old daughter to do it. She has two children but says the decision to have kids was made a lot easier when she became a successful writer.

“When you work in a hospital you know how much money you are going to earn until the day you retire and it wasn’t very much, really. I always thought I could never afford to have children because of the cost of childcare. It is very difficult working all hours in a hospital and having reliable childcare. So I honestly don’t know if I would have had children if I’d still been (working) there.”

Her medical background was really put to the test this time with her new book. The central character has cystic fibrosis, which called for some extensive research. Cystic fibrosis is a life-shortening inherited disease that mostly affects the lungs.

“I did tons of research for this, which I have not had to do before,” she says. “With something as important as cystic fibrosis you have to get it right. I’d looked at blogs and spoke to a guy who is involved in the Cystic Fibrosis Trust in the UK and he wrote a book called Smile Through It: A Year on the Transplant List.

“I’d seen many interviews with people with cystic fibrosis on TV and they always struck me as being really amazing people. Not self-pitying. Just people you would like to know.”

She adds, “The Cystic Fibrosis Trust in the UK has been thrilled and delighted with the book. I was a bit concerned when I heard that my publisher had been in touch with them but I needn’t have been as they are so happy with it. Apparently, nobody has ever written a book where the heroine has cystic fibrosis before. Because I’ve worked in a hospital I am hugely in favour of organ donation.”

The story is moving and emotional but uplifting, too. It is also written in her trademark humorous style. But wasn’t it difficult to see the funny side of such a serious condition?

“No it wasn’t,” says Mansell emphatically. “I worked in a hospital for 20 years and would often meet patients who only had a year or two to live. They would still crack jokes and be funny and laugh. People who work in hospitals get used to this black humour. I understand people who don’t may find it’s in questionable taste!

“I was careful not to do anything like that in the book but they are still normal people who just don’t know what is going to happen from one day to the next. You can have the healthiest person in the world who thinks they are going to live until they’re 100 but then something happens and boom, they are gone.”

There are no plans for her to go rogue and write a feminist science fiction book or a true crime novel. She’s happy in her literary comfort zone, even though she admits to being stuck in a routine.

“The problem is I’ve got so many people waiting for the next book. If I tried writing something different the chances are it would not be as successful. Because I write about nice characters, the kind of characters you’d like to be friends with, that’s nice for me, too. I don’t know how much I’d enjoy writing something gritty or about a mass murderer. I am probably stuck in a routine but it is a routine that I am very happy with,” she says with refreshing honesty.

So many women have told her that reading her books has given them the courage to get out of a bad relationship. Men also like to surreptitiously pick up her work and see the world from a female perspective, which in no small part has been aided by the Kindle.

“Men also read my books,” she says. “They don’t always plan to but if they are on holiday and run out of ‘manly’ stuff to read they are forced to read one of my books! They are normally pleasantly surprised. Plus they like seeing the world from a female angle.

“If there is an embarrassment factor about reading my books in public, that is where the Kindle has come in. My books have sold very well on Kindle so that has kind of worked in my favour!”

With Valentine’s Day on the horizon, there could be some furious online activity to download the book on to a loved one’s Kindle. Or even an old-school hard copy could be winging its way through the post.

“A lot of people ask for one of my books for Valentine’s Day instead of chocolates or flowers,” says Mansell.

“But maybe the important thing to remember is to be nice to each other all of the time. You should buy your loved one something or treat them to dinner when it is not Valentine’s Day. That would be great.”