DURHAM - The latest DNA analysis shows that the boyfriend of the woman who says she was raped by three men at a Duke lacrosse team party is the most likely source of sperm found in her body.

However, the director of the private laboratory in Burlington that conducted the test said it is impossible to pinpoint when the woman had sex.

"In general, if we test a vaginal swab, there's no way to determine how old the semen is on that swab," said Brian Meehan, laboratory director of DNA Security Inc. Meehan would not discuss the tests conducted in the lacrosse investigation.

As a rule of thumb, live sperm cells can live inside the body for 48 to 72 hours after sex, said Marcia Eisenberg, technical director for Laboratory Corp. of America Holdings, a forensic identity lab. Even after the sperm cells die, it is possible to extract DNA from fluid left in the body.

The sample tested by Meehan's lab was recovered from the woman during the administration of a rape kit and medical examination at Duke Hospital early the morning of March 14. This was shortly after the woman, an escort service dancer, told police she was raped during a team party at 610 N. Buchanan Blvd. that started March 13.

The lab report, requested by Durham District Attorney Mike Nifong and released to defense attorneys May 12, ruled out all 46 lacrosse players who submitted DNA samples as sources of the sperm and said there were no matches with the company's in-house data bank of 3,561 DNA profiles. The report said the boyfriend, who is not a suspect in the case, could not be excluded.

The DNA Security report said Dave Evans, one of three senior co-captains living in the rental house on Buchanan Boulevard, could not be excluded as the source of the DNA found on an artificial fingernail taken from a wastebasket in a bathroom at the house. But the report also noted that 14 of the 3,561 profiles in the company's DNA data bank could not be excluded as sources.

Nifong requested the second test by DNA Security because the Burlington lab has more sophisticated capabilities than the State Bureau of Investigation lab in Raleigh, defense attorneys said. The SBI tests showed no DNA links between the accuser and the members of the lacrosse team.

Evans, 23, of Bethesda, Md., is one of three players charged with first-degree rape, sexual offense and kidnapping in the case. The others are: Collin Finnerty, 19, of Garden City, N.Y., and Reade Seligmann, 20, of Essex Fells, N.J.

Attorneys for the three accused players have been trying to reconstruct the accuser's whereabouts and whom she may have encountered in the hours before she and another escort service dancer arrived at the team party.

As part of that effort, Kirk Osborn, Seligmann's attorney, asked Durham Superior Court Judge Ronald L. Stephens to order Nifong to turn over a cell phone the accuser left at the Buchanan Boulevard house. Stephens ordered the phone be examined and results provided to him for a review.

Where accuser went

On March 24, in her only interview with a reporter, the accuser said she was notified about 8:30 p.m. the night of the party that she was supposed to appear at the Buchanan Boulevard house about 11 p.m.

In an interview earlier this week, her father said he saw his daughter a few times March 13. That afternoon, he said, she picked up her two children from elementary school. About 9:30 p.m., he said, she brought the children to their grandparents' house for the evening.

"She was fine," he said.

After their arrival, he and his daughter took a short car ride about 10 p.m. to a neighborhood convenience store at Cornwallis Road and South Roxboro Street. He bought a pack of cigarettes but said he did not recall what his daughter purchased.

When the two returned to his house, the woman said she had to go out and wouldn't return until 1:30 a.m. He said he does not know whether she left in her own car or someone picked her up. He said she did call him to say she safely reached her destination -- about 11:30 p.m., about the start of a late-night talk show he was watching.

The man said he did not know his daughter was working as an escort that night. She didn't return until late the morning of March 14, the father said.

(Staff writer Benjamin Niolet and news researcher Brooke Caine contributed to this report.)