Underwood, 27, married her hockey player partner Mike Fisher four months ago but says kids are not in their immediate future.
Speaking to ABC show, In the Spotlight With Robin Roberts: All Access Nashville, she said: 'We just want to be together and keep it as simple as possible.
'And I think a baby would just make things so complicated right now.'
The former American Idol star added she is looking forward to the end of her tour so she can relax with her new husband.
She said: 'I'll be more home-based. So I'll get to spend, you know, my days with him. We'll be more like a normal couple.'