Woodward was booked on suspicion of murder on Sunday and held on $2 million bail, but he was released on Wednesday.
"This is a very complicated case. It is a case that will require expert witnesses. It is a case that will require extensive scientific analysis of substance," said LAPD Deputy Chief Charlie Beck during a news conference. The substance Beck referred to is an unspecified powder that sources close to the case say Woodward placed in his girlfriend's vaginal area.
Police are determined to build a case against Woodward. They believe he was the biological father of the aborted fetus.
Investigators say they are working with the D.A.'s Office to gather more evidence against Woodward. They also say they are following up on several leads in the case.
While police will not rule out criminal charges against Woodward, ABC News legal analyst Dana Cole said under California law, a murder case is unlikely.
"Normally we're looking at the third trimester before a murder charge could really apply," Cole said. "If the fetus could not have survived, it will never be a murder case. It could be an assault case, but it will never be murder."
Woodward also owns restaurants in Miami and Chicago.