The sparkle-maestro: mezzo-soprano Katherine Jenkins on babies, wardrobe malfunctions and why opera really should be for the masse

For those efforts, as well as her subsequent work with veterans’ charities and, not least, for a recording career which has racked up millions and provided seven UK classical number one albums, Jenkins was recognised in the 2014 Honours list.

Her most recent big stage outing came at the Queen’s 90th birthday concert at Windsor Castle in May, where she performed I Vow To Thee My Country clad in a Union Jack dress – though hers was a little more stately than Geri Halliwell’s famously short creation.

So if the Establishment has anything as vulgar as an official stamp of approval, Jenkins bears it, and with a degree of pride. No surprise, then, that when she married New York-born artist and film-maker Andrew Levitas, in September 2014 the venue was prestigious: Hampton Court Palace.

Almost a year to the day after her glitzy wedding, Jenkins gave birth to a daughter, Aaliyah Reign Levitas. As we speak – a conversation which takes in Jenkins’s upcoming Glasgow appearance as well as her thoughts on fame, elitism in the arts and “popera”, the word sometimes used to describe her oeuvre – I can hear Aaliyah gurgling and burbling in the background. “She wants to talk to you,” says her mother through giggles, after one particularly noisy interruption.

Juggling interviewers and babies is one thing. Juggling motherhood and a demanding professional career is quite another, especially one which comes with a paparazzi lens attached, as Jenkins’s often does.

“It’s like anything, it’s balancing it that’s the hard thing,” she says. “But I do feel like this is exactly where I should be in my life. I’m loving being a mum, absolutely obsessed with her, and so it’s a lovely balancing act. I’m back singing and I’m back at work because I’m inspired to do stuff because of her. I want her to one day appreciate what I do and I feel really proud when I get to take her to my rehearsals and to my shows. So I certainly have less time for myself, but you know she’s my priority, and my husband, and it’s just … yeah, a new adventure.”

Jenkins was told in advance that being pregnant would actually help her voice, which turned out to be true. It was one reason she continued to sing until quite late in her pregnancy – and why her unborn daughter had early exposure to a great deal of music. Will it prove beneficial in the years to come?

“She definitely heard a lot because I was on tour for the first seven months that I was pregnant, so she was hearing it live,” says Jenkins. “And I think that’s why she has an interest in music now – because she hears so much of it. We’ll see if she wants to go into music one day. Maybe she will, maybe she won’t. I certainly won’t be pushing her in either direction.”

Jenkins also kept up her exercise regime until close to the time Aaliyah was born, again with an eye on a quick return to the stage.

“I think that enabled me to be strong quite quickly after having her. Everybody has to deal with their pregnancies as they feel and listen to their bodies. But that was something I wanted to do and I think it has helped me, post-baby, in terms of singing and feeling ready to go back and perform.”

It’s no surprise she was missing it. Born in Neath in 1980 to a radiographer mother and a retired factory worker father who died when she was 15, Jenkins was singing and performing even before she went to primary school.

“I always loved it, from four years old,” she says. “Then I joined my church choir from seven and was a full-time member of that before I came to London to study.”

That’s a condensed version of the story. The slightly longer one reveals a girl with a singular musical talent and a hunger to succeed which would take her from her council house in industrial south Wales to the Royal Academy of Music in London in just a few years.

An exceptional chorister, Jenkins was a member of the National Youth Choir of Wales and in 1991 won the Welsh Choirgirl of the Year competition. At Gorseinon College in Swansea, where she studied for her A levels, she continued to sing. Then, aged just 17, she won a scholarship to study at the Royal Academy. After that, her career went stellar. By the time she was 20 she had signed a £1 million, six-album deal with record label Universal though even that fee was dwarfed by the £10 million deal she inked with Warner Music in 2008.

Now back on the Decca label, Jenkins hasn’t matched the successes of a decade ago, when the five albums she released between 2005 and 2009 – Living A Dream, Serenade, Rejoice, Sacred Arias and Believe – all settled high up in the top 10 album chart and each topped the UK classical chart. But she remains the UK’s biggest “crossover” star, a neutral enough term used to describe those with a foot in both the classical and the pop worlds.

“To me it means somebody who’s had training in the classical world so can operate in that space, but who also has an interest in making the genre more popular and accessible,” she says when I ask her to define the term. “I think it’s a mixture of commercial opportunities with classical training, and being able to do concerts of both style.”

And is she comfortable with the description? “I think it’s one of the better ones,” she says. “There’s things like ‘popera’, which I don’t really like. But ‘crossover’ gives the idea of spanning two genres and I think that’s what it is. It’s spanning classical and pop.”

If Jenkins has any sort of political message to convey based on her background, her route into singing and her position as a crossover artist, it’s this: opera and classical music need to be re-framed as non-elitist activities which anybody should be able to enjoy, either as participant or audience member.

“I think it’s about taking out the bits that make people feel uneasy or excluded, and making it feel very accessible,” she says. “Letting people go to concerts or access opera performances, for example, where ticket prices are hugely expensive, and doing them sometimes in pop venues.”

She’d also like to see more opera performers appearing in non-traditional venues, places “you wouldn’t expect”, as she puts it, “like Renée Fleming performing at the Superbowl”. Fleming became the first opera singer to perform at that famous American sporting event, singing The Star-Spangled Banner at the 2014 final. “That’s a great way to get people interested in performers. And you never know, seeing Renée at the Superbowl might one day lead someone to go and see her at the Met [New York’s famous Metropolitan Opera].”

I tell her about the visit my daughter’s primary school will soon be having from Scottish Opera, part of a long-running schools education programme which the national company claims gives 10,000 children a year a taste of live opera. She’s delighted at the prospect.

“I think it’s so important,” she says. “Music is one of the first things to get cut in education programmes so it’s really important that children from all backgrounds get the opportunity to experience culture and the arts. So for children to see opera up close and personal is amazing and that makes me really excited.”

Jenkins herself visits Glasgow’s Royal Concert Hall next month to perform songs from her most recent album, Celebration, a collection of hymns, anthems and favourites from stage musicals. It also includes a cover of David Bowie’s Heroes.

She’ll be joined on stage by the Scottish Chamber Orchestra for what she calls her “Christmas celebration tour”, though she adds: “When I say celebration I mean the anthemic, celebratory, uplifting music that I tried to create for the album but not just specific to the album. So Christmas music, community singing, folk songs and things from around the UK as well as some of the most requested songs from all of the albums … I’m wanting to get everyone in the festive spirit. Things can be a bit stressful in December, so it’s nice to sprinkle some sparkle over everybody and get them singing along and remembering what it’s all about.”

So any Slade covers planned? She isn’t saying, though if 2012’s This Is Christmas album is anything to go by, the festive selection will be more Nat King Cole and Bing Crosby than Noddy Holder and Roy Wood.

Jenkins’s Glasgow show is part of an 11-date tour of the UK and Ireland which ends with a concert at London’s Barbican on December 27. The singer is at least taking Christmas Eve, Christmas Day and Boxing Day off to spend with the family, but it’s clear that even with millions or records sold and millions of pounds banked, performing live is still the heartbeat of her art, still the thing she keeps coming back to and which, you feel, she cannot do without.

“It is my favourite part,” she admits. “Aside from standing on stage and seeing how music affects people and how they interact with it, it’s also just lovely seeing people on the road, getting to meet them after the concert and catch up with some of them who have been very kind in following my concerts for a long time.

“I love going into the studio and getting the opportunity to be a perfectionist and focus on one thing as long as possible – but nothing beats the aspect of seeing how you can make somebody laugh one moment and cry the next. And how things can go wrong and how that can be a really funny moment that you’ll remember from a concert.”

I’m amazed. Surely after all that rehearsing, nothing ever goes wrong?

“Oh yeah,” she laughs, “they go wrong all the time. The other day I was singing at Raymond Blanc’s music festival in Oxfordshire and I went to hit a high note, took a deep breath and my dress pinged open at the back at the neck. I thought ‘Oh my gosh, it’s going to fall down now’ and I sang the rest of the aria thinking, ‘Please don’t fall! Please don’t fall!’ So there can be things like that, technical things, forgetting the words on occasions. You’ve just got to go with it and be honest with the audience and hopefully that makes you human. Everyone makes mistakes every now and again.”

Even a Royal Academy-trained singer and recording star who is, by her own admission a perfectionist (see above)? Yes, even her.

Katherine Jenkins is at the Royal Concert Hall, Glasgow on December 20