Serena Williams suffered a pulmonary embolism last week and underwent emergency treatment at Cedars-Sinai Medical Center in Los Angeles for a hematoma on Monday, her representatives have confirmed.

"The hematoma was another unexpected scare that was subsequently removed ," her representative Nicole Chabot said in a statement. "Thankfully everything was caught in time. With continued doctor visits to monitor her situation, she is recuperating at home under strict medical supervision."

Williams discovered the pulmonary embolism [a blood clot in the lungs] when she returned to her home in Los Angeles after being in New York for doctors appointments for ongoing issues with her injured foot.

"Thank you everyone for all of your prayers, concerns, and support," Serena said in a statement. "This has been extremely hard, scary, and disappointing. I am doing better, I’m at home now and working with my doctors to keep everything under control. I know I will be OK, but am praying and hoping this will all be behind me soon. While I can’t make any promises now on my return, I hope to be back by early summer. That said, my main goal is to make sure I get there safely."

ESPN analyst Dr. Michael Kaplan called the clot "life-threatening" and said that Williams may be out a minimum of six months and could be out as long as a year. He believes that she will be put on an aggressive course of blood thinners and that her doctors will not want to have risk falling on court and hitting her head, which he said, "could be catastrophic. I think they are looking a year if they want to be cautious."

On Monday, Serena tweeted "tough day."

Serena's sister, Venus, was scheduled to speak at a "Women of Influence" conference in Toronto on Wednesday. It's unclear whether she will fly to Los Angeles afterward.

Her mother, Oracene Price, tweeted on Wednesday that Serena "is fine."

Serena, who has been out since Wimbledon due to a foot injury, was scheduled to show up in Germany in early April for the United States' Fed Cup tie. She would risk her eligibility for the 2012 Olympics if she didn't appear on site. Given how unlikely it is that she'll be able to make that trip, her eligibility for the Olympics will now rest in the hands of Olympic Committee. She will have two more opportunities to appear at or play a Fed Cup tie next year.

—Ed McGrogan and Matthew Cronin