The 35-year-old professional tennis player, who announced she was expecting her first child with fiancé Alexis Ohanian in April 2017, revealed she broke the baby news to Ohanian on the eve of the Australian Open in January 2017.
She did it by handing him a paper bag containing six positive pregnancy tests.
“It just doesn’t seem real,” Williams told Vanity Fair.
“I don’t know why. If you would have told me last year in October or November that I would have a baby, not be pregnant but have a baby, I would have thought you were the biggest liar in the world.
“This is kind of how I am right now. This is happening sooner than later, and it’s going by so fast.”
Williams explained that she suspected she may be expecting in January 2017, after feeling different physically.
She said she had unexpectedly thrown up and her breasts were enlarged, but it was her friend, Jessica Steindorff, who encouraged her to do a pregnancy test.
Now, she is looking ahead to the baby’s arrival, as she starts to prepare one of the guest rooms in her house to become the baby’s bedroom.
“I don’t know what to do with a baby,” she added. “I have nothing, I’ve done absolutely nothing for the baby room.”
Williams revealed in April 2017 that she “accidentally” announced she was pregnant by sharing a photo on Snapchat.
“I was just saving them (for myself). I’ve been so good about it, but this was the one time it slipped.”
After her pregnancy was revealed, Williams shared a touching message on Instagram to her unborn baby.
“My dearest baby,” Williams wrote on Monday 24 April. “You gave me the strength I didn’t know I had. You taught me the true meaning of serenity and peace.
“I can’t wait to meet you. I can’t wait for you to join the players’ box next year.”