Britain's Jessica Ennis-Hill says winning a heptathlon gold medal in the World Championships is 'among her greatest feats'.

Script: SOUNDBITE (English) Jessica Ennis-Hill, Heptathlon world champion:

(On winning the world title after giving birth).

"Without a doubt, one of the greatest things I have done. Just having achieved what I achieved before having my son, and being able to get back into training and deal with all the challenges (and) injuries and all those kind of things this year and come back to win a world title is really, really amazing."

SOUNDBITE (English) Jessica Ennis-Hill, Heptathlon world champion:

(On back-to-back Olympic titles and possible retirement afterwards).

"To win another Olympics is something that not many athletes have done back to back - so that would be an incredible achievement. I think it is going to be a very, very difficult ask. And so much can change in a year. But definitely that's what I am working on. I am definitely going to get back into training. And train hard to be in the best shape I can possibly be to contend for a medal in Rio. And then we will take it from there and see what happens."

SOUNDBITE (English) Jessica Ennis-Hill, Heptathlon world champion:

(On doping).

"I think every athlete wants their sport to be clean and the more true performances we see, the more athletes that are getting caught and are coming to light is really, really great because we're making a change in our sport. Obviously, it is sad to read in the press but, I've said before, there are so many athletes that train so hard and really deliver true performances on the track and we want to see more of those."

SOUNDBITE (English) Jessica Ennis-Hill, Heptathlon world champion:

(On contacting Sebastian Coe, the president-elect of the IAAF, to hurry up appeal).

"I haven't but I think obviously Seb (Coe) is in a really great position now. And I think he is going to do a lot of good for the sport so it's really great that he is there now."