Serena Williams and Alexis Ohanian are expecting their first child, she announced on Snapchat Wednesday

By Jen Juneau
April 19, 2017 11:35 AM

Serena Williams is pregnant!

The tennis champ and her fiancé, Reddit co-founder Alexis Ohanian, will welcome their first child in the fall, her rep confirms to PEOPLE.

“20 weeks,” Williams, 35, captioned a mirror selfie on Snapchat Wednesday, where her baby bump is clearly visible underneath a La Blanca Anniversary Suit created in a custom yellow color just for the mom-to-be.

Later on Wednesday, a rep for the tennis star told PEOPLE, “I’m happy to confirm Serena is expecting a baby this fall.”

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Source: Serena Williams/Snapchat

Notably low-key and private couple Williams and Ohanian, 33, were engaged in December, with the athlete breaking the news on Reddit via a poem.

“I came home. A little late. Someone had a bag packed for me. And a carriage waited. Destination: Rome,” she wrote. “To escort me to my very own ‘charming.’ Back to where our stars first collided. And now it was full circle. At the same table we first met by chance.”

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Williams added, “But by choice. Down on knee. He said 4 words. And I said yes.” Ohanian cross-posted his fiancée’s Reddit announcement on Facebook, captioning it simply, “She said yes.”

Williams holds the record for the most Grand Slam titles of any player in the Open Era, clinching her 23rd at January’s Australian Open.

This will be the first child for both.