PACIFICA (CBS SF) – Preliminary results from an autopsy performed Friday on a pregnant woman found mauled to death in her Pacifica home show that one of her two pit bulls was likely responsible for killing her, police said Monday.

Darla Napora, 32, was found Thursday afternoon when her husband came home from work and said their 2-year-old male pit bull was hovering over her badly mauled body, according to police.

READ MORE: Attorney General's Office: Man Shot Dead by Police at SFO Armed With Replica Gun

Efforts to revive Napora were not successful and paramedics declared her dead at the home.

The dog believed to have been responsible for the attack was shot and killed by police when it escaped from a backyard enclosure and approached emergency responders.

An autopsy conducted by the San Mateo County coroner’s office concluded that Napora died from a combination of shock and blood loss from dog bites, police reported today.

READ MORE: San Francisco 49ers Confirm DE Bosa Cleared to Play Against Packers

Preliminary results from a necropsy preformed on the deceased pit bull showed the dog was likely the only animal that took part in the fatal attack. Investigators collected tissue samples, blood evidence and teeth impressions from the suspected dog and the second pet pit bull, a female.

Two forensic odontologists, or bite experts, compared the teeth impressions with bite marks on Napora and concluded that the wounds on her body were consistent with bites from the suspect male dog, according to police.

There was no evidence of any other trauma suffered by Napora that led to her death. Complete and final results from the autopsy and necropsy will not be available for at least two weeks.

The female pit bull remained in custody at the Peninsula Humane Society.

MORE NEWS: Sonoma State Receives $1M Grant To Study California Wildfires, Forest Health

(Copyright 2011 by CBS San Francisco. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)