Beyonce has led celebrities in congratulating Serena Williams on her new baby.

The tennis star, who is engaged to Reddit co-founder Alexis Ohanian, was admitted to St. Mary's Medical Center in West Palm Beach, Florida, on Wednesday (30Aug17).

Her coach Patrick Mouratoglou took to Twitter on Friday to confirm that Serena had given birth to her first child, a baby girl, with Hollywood's A-list quickly reacting to the news.

Beyonce, who gave birth to twins Rumi and Sir in June, took to Instagram to share a photo of a pregnant Serena, which she captioned, "Congratulations Serena!"

While Ciara wrote a message on Twitter, stating, "Congratulations to my girl @SerenaWilliams & Alex Ohanian on your new baby girl! So happy for you guys!"

Serena's longtime pal Karlie Kloss did the same, with the model writing, "Congratulations @SerenaWilliams and @alexisohanian on your beautiful baby girl! ...Auntie Karlie is ready to babysit."

And Wendy Williams couldn't help but incorporate a pun into her congratulatory message.

"You Reddit here first! Serena Williams and Alexis Ohanian had their baby. Congratulations!" the TV host captioned a snap of Serena and her beau.

Serena, 35, was about two months pregnant when she won her 23rd grand slam singles title at the Australian Open in January. Accordingly, the tennis community has also reached out to the sportswoman over her baby news.

Her sister Venus Williams spoke to ESPN moments before stepping onto the court for her U.S. Open match in Queens, New York on Friday afternoon, and shared, "Obviously, I'm super excited. Words can't describe."

Meanwhile, tennis legend Billie Jean King took to Twitter to write: "So excited for you & @alexisohanian! Can't wait to see you, hold your little girl and squeeze her tiny fingers + toes."

In addition, Rafael Nadal wrote, "Congrats Serena!!! So much joy for you!!!" and Boris Becker added, "@serenawilliams had baby girl !!! Congrats from NYC."

Serena and her fiance Alexis, who became engaged in December, have yet to comment on news of the birth of their baby girl.