Barbro Holmberg was taken by ambulance to Health Central Hospital after someone called 911 about 2:35 a.m., hospital spokesman Dan Yates said. She was released about 11 hours later and returned to Woods' home, Yates said. He said he could not be more specific about her ailment because of privacy laws.
Holmberg, who arrived in the U.S. a few days ago, lives in Sweden and is the mother of Woods' wife, Elin.
Health Central is the same hospital where Woods was treated after he crashed his sport utility vehicle outside his home in the gated Isleworth community in Windermere last month.
Yates said Holmberg had been in a private room and the family had hired additional security to keep the media away. He said family members visited, but he would not say which ones.
Media attention has been focused on the world's No. 1 golfer since he hit a hydrant and a tree around 2:25 a.m. on the Friday after Thanksgiving.
The Florida Highway Patrol last week cited Woods for careless driving and fined him $164.
The accident - and Woods' refusal to answer questions about it - fueled speculation about a possible dispute between him and Elin.
Just days before the crash, a National Enquirer story alleged Woods had been seeing a New York nightclub hostess, Rachel Uchitel, who has denied it. After the crash, Us Weekly reported that a Los Angeles cocktail waitress named Jaimee Grubbs claims she had a 31-month affair with Woods.
Last week, Woods issued a statement saying he had let his family down with unspecified "transgressions" that he regrets with "all of my heart." He did not elaborate.
A police report on the crash released Monday showed that a Florida trooper who suspected Woods was driving under the influence sought a subpoena for the golfer's blood results from the hospital he was taken to after the crash, but prosecutors rejected the petition for insufficient information.
A witness, who wasn't identified in the report, told trooper Joshua Evans that Woods had been drinking alcohol earlier. The same witness also said Woods had been prescribed two drugs, the sleep aid Ambien and the painkiller Vicodin.
The report did not say who the witness was but added it was the same person who pulled Woods from the vehicle after the accident. Woods' wife has told police that she used a golf club to smash the back windows of the Cadillac Escalade to help her husband out. His injuries were minor.
The sister of a neighbor who called 911 after the crash told troopers that Holmberg and Woods' mother were also at the scene, but the AP has not been able to confirm that.
Eva Malmborg, a spokeswoman for Holmberg, said she was informed by a family member that Holmberg was admitted to a hospital in Florida due to stomach pains but was feeling well "considering the circumstances."
Malmborg said that as far as she knows, Holmberg doesn't suffer from any disease.
Holmberg's deputy, Olov Rydberg, said in a statement that Holmberg is expected back at her job as Gavleborg county governor in central-east Sweden next week.
Associated Press Writers Mike Schneider in Orlando, Antonio Gonzalez in Windermere and Louise Nordstrom in Stockholm contributed to this report.