Paula Radcliffe has admitted for the first time she has put motherhood on hold to pursue her athletics career.
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Radcliffe, 31, and husband Gary Lough believe it would be "selfish" to have children while she is still competing.
"I do badly want a family," she told Saturday's The Times Magazine. "But it would be selfish at the moment because we move around so much."
She added: "Both of us want, when we have kids, for them to be the centre, not my running."
Radcliffe admitted that the couple would have been trying for a baby sooner if she had won the Olympic marathon in Athens.
"We're coming round to it [the idea of having children]," said the marathon world record-holder.
"I don't want to think because of my running I left it too late."
But she also left the door open for an appearance at the Beijing Games in 2008.
"I could carry on after having children; physically it makes your body tougher," she said.