Jessica Ennis-Hill has revealed that she still can't believe she was able to win gold at the World Athletics Championships in Beijing.

The reigning Olympic champion added a second world heptathlon title to her honours list on Sunday despite having only returned to competitive action in May following the birth of her first child.

The 29-year-old admitted that the journey back to the top of her sport has been harder than she expected, but insists that she is "really proud" of her achievement.

"Before you become a parent, you think it will be easy. Then you're thrown into it and realise it's incredibly hard. I would be lying if I said I didn't have moments when I thought: 'What am I doing?'," she told BBC Sport.

"This time last year, I couldn't imagine stepping back on the track, let alone being at the World Championships and winning. I underestimated how hard it would be. There's always that worry and anxiety and you think: 'Am I going to be able to get back to my best?'

"We never talked about medals and I still can't believe it has happened. I'm really proud of what I've been able to do. I'm so glad it has all been worthwhile and I can take my shiny medal back to my son."

Ennis-Hill previously won gold at the 2009 World Championships in Berlin, before following that up with silver two years later in Daegu.