Maksim took to Twitter on Wednesday (04Jan17) to announce Peta, 30, had given birth to a baby boy in New York earlier that morning.

"Shai Aleksander Chmerkovskiy," he simply tweeted. "01/04/17 5:34am."

The 36-year-old has been keeping fans updated of the pregnancy on social media in recent weeks. On Monday (02Jan17) he posted an Instagram video after they reportedly got kicked out of Lamaze Method childbirth class because "Peta was misbehaving and not listening to anything."

More recently he shared a video of them apparently en route to the hospital while it was dark.

"Hoping for a very smooth delivery for Peta and hope Maks doesn't pass out! Best of luck to a very healthy little guy and God Bless you all," he said, shortly before sharing a picture of Peta applying make-up while sat on a hospital bed.

The couple has been dating on and off since 2012 and Maksim proposed onstage following a performance of their show Sway: A Dance Trilogy in Miami, Florida in December, 2015. They reportedly plan to get married later this year (17).