The 35-year-old announced on Twitter that she is expecting her baby in August, and will be heavily pregnant as she guides Murray through Wimbledon.
She shared a photo of her worn plimsolls alongside a teeny tiny pair of All Star trainers and wrote: "Baby will be here in august! #pregnant So happy."
Andy, 27, marries long-time fiancee Kim Sears at Dunblane Cathedral on Saturday.
Amelie, who won Wimbledon and the Australian Open titles in 2006, came out as gay at the 1999 Australian Open.
She was appointed as Andy's coach in June 2014 following his split from Ivan Lendl three months earlier.
Much of the initial debate around her appointment centred on whether she could instil a more aggressive attitude in the Scotsman.
He was forced to defend her appointment, saying: "She was someone who struggled with nerves and conquered them later in her career. Someone like that can help more than someone who hasn't had those issues before.
"You can talk about Amelie's accomplishments, she won a lot. She was No 1 in the world, she won multiple Grand Slams, she had a creative game style.
"As a person, she is very nice, very easy to communicate with, but she is firm as well. So those are the reasons I wanted to give it a shot."
After his defeat to Novak Djokovic in America last week, Andy has had to put tennis aside this week as he and Kim make last-minute preparations for their wedding.