A quick tour of London’s theatres this month would come as quite a shock to those who think opera is all about ten-ton maidens dying of consumption and agitated Teutonic gods splashing around with mermaids. At the Barbican, Tom Adès’s Powder Her Face has an aria sung by a heroine (the late Duchess of Argyll, no less) as she satisfies her lover orally. Yes, she does sound a bit muffled. At the Coliseum, John Adams’s Nixon in China literally makes a song and dance out of global politics. Henry Kissinger has rarely seemed so entertaining.

But the summer’s most startling opera has to be Push!, which opens next week at the Riverside Studios, London, and then tours the country (www.pushopera.com for details). The strange title? Surely it can’t be about . . . Well, yes it is. Men of a squeamish disposition should look away now. Push! is the world’s first opera about childbirth.

And to ensure that the message is properly delivered, as it were, no fewer than six mothers are portrayed, simulating the birth of ten babes (one mum has quintuplets). Now why didn’t Puccini think of that? This may sound like too much of a gynaecological thing, even for those pressing for opera to be “relevant to ordinary people”. But though I can’t vouch for David Bruce’s music, I have read Anna Reynolds’s libretto, and it’s a lot wittier than I feared. Less about the physicality of the birth process itself (though plenty of yelling is involved), more an emotional journey through the mental states of six different women — joyous, fearful, distressed or bitter — as they face the greatest of life’s pivotal moments.

“So many operas are about arcane things,” says the director, Bill Bankes-Jones. “This is a universal subject.” But he admits to being surprised by the advertising angle taken by the Cambridge Arts Theatre, where Push! plays in July. “Book for this,” its website suggests, “if you enjoyed The Vagina Monologues.”

Bankes-Jones’s nine-year-old company, Tête à Tête, has spearheaded the drive to break down stereotyped expectations about opera. Four years ago, for instance, the company collaborated with London’s homeless to produce a stunning staging in Westminster Abbey of Benjamin Britten’s Canticles. Push! itself was developed through the Genesis Opera Project, a scheme financed, to the tune of a million quid, by John Studzinski, the high-flying City banker who regards such generous patronage as part of his Christian witness, and sees unusual new operas as feeding into “a new spiritual movement”.

Such patrons are much needed. As Bankes-Jones points out, there is little new work coming at present from the big opera houses. “They haven’t got the nerve,” he says scathingly. “And they haven’t the machinery to nurture young composers and librettists. It’s a bleak time for new opera.”

He has a point. All the more reason, then, to catch Push!. And Tête à Tête’s marketing is no less inventive than its choice of subjects. “Come dressed in a nurse’s uniform and get in free!” its brochure promises. You don’t get that sort of offer from Covent Garden.