A Romanian woman who collapsed at National Airport Monday as she was about to fly home after her diplomat husband's defection has now asked for political asylum here, State Department spokesman Thomas B. Reston said yesterday.

The woman, Christian Horodinca, made the request yesterday shortly before federal officials whisked her away from the Arlington hospital where she was treated to an undisclosed location, sources said.

State Department officials are now considering the woman's request for asylum for herself and her 3-year-old son, sources added.

On Feb. 24 the woman's husband, Nicholae Ion Horodinca, a former third secretary at the Romanian Embassy, defected to the United States by turning himself in to military police at Fort Belvoir. He also has asked for asylum and is being kept in protective custody in the Washington area, sources said.

Mrs. Horodinca's stay at National Orthopaedic and Rehabilitation Hospital had threatened to develop into an international incident. While she was being treated in the hospital's emergency room Monday afternoon six Romanian Embassy employes tried to walk out with her son, observers said.

They were stopped at the hospital's doors by uniformed Arlington County police called by worried hospital officials, sources said.

Christina Horodinca left the hospital at about 1:30 p.m. yesterday after a tense five-minute meeting with Romanian Ambassador Nicholae Ionescu and State Department officials, according to hospital spokesman Robert Moorman. State Department and Romanian Embassy officals declined to comment on the meeting.

U.S. officials were puzzled by the woman's change of heart at the airport on Monday, because she had previously indicated to them that she wished to return to Romania. State Department spokesman Reston said he had no idea why she changed her mind.

Horodinca was recognized in the emergency room on Monday by Dr. David Corcoran, as he treated her for dizziness and fainting. Corcoran knew her husband socially, sources said.