The 35-year-old Wimbledon champ is showing off her growing baby bump on the cover.
RELATED: Venus Williams may have revealed Serena is expecting a baby girl
This is for the August issue of the magazine. Williams details how she found out she was pregnant - taking six pregnancy tests.
She also reveals how she fell in love with her fiancé, Alexis Ohanian, the co-founder of San Francisco-based Reddit.
The couple is planning to get married in the fall, after the baby is born.
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