Proposition 4 would change that, and require parents be notified.
"The same sort of thing that has already, by the way, been made law in 35 other states," said Don Sebastiani from Yes on Proposition 4.
Proposition 4 would require doctors notify parents 48 hours before performing an abortion on anyone under 18 years old. The parent does not have to consent, but they must be told.
Two very similar measures were already on the ballot in 2005 and 2006.
Doctor Mary Davenport has been on the front lines, fighting for parents to be told about abortions.
"It can have really serious health consequences and I just can't imagine this taking place without parents or the people closest to the girl knowing about it," said Dr. Davenport.
Both earlier measures were defeated, so this time, supporters have made a change.
Under Proposition 4, if a girl is afraid she'll be abused when her parents find out she wants an abortion, the doctor can tell another adult relative instead.
"Just the notification of really any adult that can come to a girl's aid and provide her some counsel. We would hope that would be mom, but we know that's not always the case," said Sebastiani.
A pregnant teen could also ask a judge to waive the notification requirement.
Sebastiani is a former state assemblyman - and a spokesman for the yes on 4 campaign.
"People who are on the pro-choice side and on the pro-life side -this something they can agree on," said Sebastiani.
But not everyone does agree.
"Teens that know they have to tell their parents before they get an abortion may feel trapped. We have the very real concern that young women will take matters into their own hands, consider a back alley abortion, or even consider suicide," said Maya Ingram from Planned Parenthood.
The campaign against proposition 4 is being led by Planned Parenthood. Their volunteers are calling voters all over the state.
"When you talk to them more about it and they see that laws like this can't mandate family communication and the desperate situation it would put young women in, then they generally do the right thing and they want to get out and vote no," said no on Prop 4 volunteer Tiffany Nurrenbern.
Planned Parenthood says their health care providers already urge girls to talk to their parents before getting an abortion, and most girls do. But for those from abusive homes, even talking to a relative other than their parent could be dangerous.
"You can only notify another adult family member if you report your parents for abuse and then a criminal investigation will ensue, leaving a young woman in a vulnerable situation," said Ingram.
Supporters of Proposition 4 say reporting abusive families will help teens, not hurt them and they believe Proposition 4 will protect underage girls from predatory older men.
"Every place where parental notification has passed, we have seen a decline in teenage pregnancies. We've seen a decline in abortions. We've seen a big sharp decline in sexually transmitted diseases," said Sebastiani.
But Planned Parenthood says girls just go out of state to get abortions, or they put them off because they're afraid to tell their parents and end up having riskier late-term abortions.
Supporters say if they lose again on this ballot measure, they'll be back and keep trying until they win.
Written and produced by Jennifer Olney.