Tennis star Serena Williams confirms she is pregnant after Snapchat selfie

Tennis star Serena Williams is pregnant with her first child.

The 35-year-old's spokeswoman confirmed the news hours after Williams posted a picture on Snapchat of herself in a yellow swimsuit with a prominent bump, with the caption "20 weeks".

Her baby is due in the autumn, the spokeswoman said.

Williams announced her engagement to the co-founder of the website Reddit, 33-year-old Alexis Ohanian, in December after dating for more than a year.

Earlier this week she posted an Instagram photo of the couple enjoying time on a beach.

The baby news means she will miss this year's Wimbledon, having previously won the tournament seven times.

In January, Williams beat her sister Venus in the Australian Open final to win a record-breaking 23rd Grand Slam.

The win meant she surpassed German Steffi Graf's 22 Grand Slam titles in the Open-era.

The Australian Open was her last competitive match, as in March she pulled out of the BNP Paribas Open at Indian Wells and a WTA Tour event in Miami.

At the time she blamed the withdrawal, which meant she lost her number one world ranking to Angelique Kerber, on a knee injury.

Williams claimed her first Slam - the US Open - 18 years ago.