From John Peel indie favourite with 10,000 Maniacs to impassioned socio-political crusader, Natalie Merchant's career has undergone many twists. But none, perhaps, quite as curious as this. Absent from the scene since becoming a mother in 2003, the singer explained that she became fascinated with how people down the centuries viewed the experience of childbirth. Thus, she is performing songs from Leave Your Sleep, an album setting (mostly) 19th-century children's poetry to music.

Any fears of a dull, worthy affair were soon banished as she grinningly describes "collaborating with people who are dead" and fleshes out the music with tales of the poets' lives. Her fitted black dress gave her the aura of a sensual schoolteacher as she explained how Robert Louis Stevenson wrote The Land of Nod – about returning to childhood through dreams – while he thought he was dying of consumption, and that EE Cummings was inspired by "cavorting with prostitutes".

The stripped-down format – the album's 130 musicians were replaced by just guitars and cello – was arguably superior, as it focused attention on her stunning voice: a crystal mix of innocence and frets. Performing under portraits of the poets, she made their words sound real and exciting.

The songs span the childhood experience from joy and hilarity – hauling a man up from the crowd to read Edward Lear's limericks – to disillusion and horror with haunting takes on the likes of Charles Causley's Nursery Rhymes of Innocence and Experience.

Previously uneasy with her past, Merchant seemed as delighted as the audience to rediscover her back catalogue, whether a simmering Motherland or Tell Yourself, her stunning advice for a 13-year-old girl. This is an evening of the magical power of words and music: at 46, Merchant may be in her prime.

At Symphony Hall, Birmingham tomorrow (0121-780 3333), then touring.