Last week Serena Williams took to social media to announce that she's 20 weeks pregnant with her first child. More recently, Serena took to social media again, this time to call out tennis legend Ilie Nastase who made some derogatory remarks about her unborn baby during a tennis event last weekend.

According to ESPN, at the Fed Cup draw in Romania, Nastase, the former world number one, was heard speaking to one of his former teammates about Serena's baby.

"Let's see what color it has. Chocolate with milk?"

The International Tennis Federation has since launched an investigation into those comments, saying they "do not tolerate discriminatory and offensive language and behavior of any kind."

Serena shared her own message about Nastase, which reads in part,

"It disappoints me to know we live in a society which people like Ilie Nastase can make such racist comments towards myself and unborn child, and sexist comments against my peers."

"I am not afraid unlike you. You see, I am no coward. Does my sassiness upset you? Why are you beset with gloom? You may shoot me with your words... you may try to kill me with your hatefulness, but still like air, I rise."

Check out Serena's full comments, as posted on her IG page, below.