Cycling star Lance Armstrong, a testicular cancer survivor and Tour de France champ, announced he is the father of a newborn son on Friday.

Armstrong announced via Twitter that Max — weighing seven pounds and five ounces — was born overnight.

In a posting on his Twitter page Armstrong displayed a picture with the caption “Wassup, world? My name is Max Armstrong and I just arrived. My Mommy is healthy and so am I!”

Armstrong announced last December that he and Anna Hansen — an actress and one-time beauty queen — were expecting their first child together.

The cycling champ has three children with ex-wife Kristin.

Armstrong, a seven-time Tour de France winner, recently returned to the saddle in a a bid to replicate past Tour de France glories.

He has regularly communicated with fans and journalists alike by posting messages on the Twitter social networking website.