While they haven't actually released a statement, E! News saw Mila hanging around a prenatal class in LA, so that's all the confirmation the internet requires.
The 30-year-old actress is expecting her first child with That '70s Show co-star Ashton Kutcher, to whom she recently got engaged.
Meanwhile, a source told People.com: "They are both very, very happy. It's still early."
The pair sparked engagement speculation after 30-year-old Mila was spotted with a huge diamond ring last month, but they aren't expected to rush down the aisle in light of their baby news.
The insider added: "It won't necessarily be a short engagement. They haven't begun planning the wedding yet." Well, if she is pregnant, they can add at least 18 months to their long engagement.
The couple began dating furiously in 2012 following Ashton's split from ex-wife Demi Moore, but they have known each other for years after playing the lead roles in hit 1990s (yep, the 90s) sitcom That '70s Show. More recently they starred together in this kiss cam shot during some sports event.
Ashton, 36, is thought to have had a crush on his co-star when they worked together, but their romance didn't bloom until years later. A source previously said: "He was so in love with [Mila] for a while when they worked together. He thought she was a goddess, was always talking about how beautiful she is.'
'Jupiter Ascending' star Mila recently opened up about her low-key date nights with Ashton, revealing they enjoy 'white T-shirt nights'. That's "white T-shirt competitions - apologies - nights.
She explained: "We have a thing called white T-shirt night and it's when you wear jeans and a white T-shirt and you go on a date. Nothing fancy, it's just something that you love to do - whether that's bowling or dinner or going to a cheese shop and have some wine or walking around. I think that's just the best thing to do, and sometimes it's just nice to stay home."