Sagan announced the news on Twitter, with a picture of him and his wife and the caption "I guess this is not from the pancakes. Life is all about love!"
The couple have been together for a number of years, getting married in 2015 with Peter sporting a typically flamboyant outfit at the ceremony.
Of course it didn't take long for a few to start predicting cycling greatness from the unborn Sagan...
Sagan announced the news less than two weeks before the start of the Tour de France, where he will take to the start line in Düsseldorf looking to win his six successive green jersey.
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