It's the private rather than the professional lives of the show's stars that have been hogging the headlines recently, with Ellen Pompeo welcoming a baby girl called Stella Luna and Katherine Heigl adopting a daughter from Korea.

"There's a lot of breeding going on in our show," Patrick joked.

"There's a lot of love scenes so it might be from that. Who knows?"

He said he's looking forward to welcoming his fictional wife (played by Ellen) back on set after the birth of her daughter, but that off-screen, his relationship with his co-stars is strictly professional.

"I think because we've been working together for so long people want to get back to their families. We start at five in the morning and get back at nine at night so we're together a lot, and when you're not working you definitely want to get back to your families and pick up where you left off," he revealed.

:: The sixth series of Grey's Anatomy begins on Living on Thursday, January 21