The discovery was made on the northbound 5 transition ramp to the westbound 22 Freeway around 2:44 a.m.
The woman was identified as Martha Rodezno of Los Angeles. Her cause of death has not been identified. An autopsy is scheduled for the coming week.
"We don't know if she was in a vehicle and jumped out of the vehicle. We don't know if she was thrown out of the vehicle," said Santa Ana police Cpl. Anthony Bertagna.
Rodezno's parents, who live in Boyle Heights, are grieving the death of their daughter, the mother of three children.
"This happened last night, but he doesn't know anything. He just found out today at 1 in the afternoon. He's still in shock," Carlos Lopez, the woman's father, said through a translator.
Lopez says he last saw his daughter on Thursday.
Police have learned that Rodezno was attending a family gathering in Mission Viejo Saturday night. At midnight, after becoming upset about something, authorities say she left the gathering on foot.
Investigators believe Rodezno walked to the area of Avery Parkway and the 5 Freeway in Mission Viejo; that's the last place she was seen alive. It's not known if she was with someone, or how she ended up in Santa Ana.
Anyone with information about this suspicious death investigation was asked to contact the Santa Ana Police Department at (714) 245-8390.
