"Officially switching to zone defense! Our family couldn’t be more excited to welcome baby #3 soon!", says Woznicki in announcement on X.
A number of tennis stars flooded her post with well wishes.
“Congrats!!!!! Can’t wait to see another beautiful baby made by you guys,” Genie Bouchard said.
Karolina Pliskova wrote: “No wayyyyyyy unstoppable. Big congrats.”
Carla Suarez Navarro said: “Congrats super family!!”
Wozniacki and Lee tied the knot in 2019, the same year she announced her retirement from tennis.
It is not clear from the social media post whether the pregnancy will have consequences for her tennis career.
In March, she withdrew from the national team's upcoming matches against Slovakia and the USA in the Billie Jean King Cup, which will be played on 11-12 April.
The 34-year-old has been absent since last year’s US Open, citing her ongoing battle with rheumatoid arthritis as the reason. As a result of her inactivity, she has dropped to number 127 in the world rankings.
She resumed her career in the summer of 2023 after a 3.5-year break. Now the question is whether and when she will be in action again.