LOS ANGELES — Backers of an initiative to require doctors to notify parents when a minor seeks to have an abortion have until Aug. 19 to submit enough valid signatures to qualify the measure for the ballot.

The initiative would require that a girl wait 48 hours to have an abortion after the physician or other medical professional notifies her parent or legal guardian in writing.

Exceptions would be provided for a medical emergency, parental waiver or parental abuse documented by notarized statement from law enforcement or certain relatives.

A judge also would be allowed to waive the notice requirement if the girl appears in court and proves maturity or a waiver is in her best interest.

Reporting of specific abortion information to the state would also be required.

If the initiative were to become law, it would result in state administrative costs of at least $1 million and potentially several million dollars annually, according to an analysis prepared by the Legislative Analyst and Department of Finance.

The net fiscal impact on state health and social service programs is uncertain but is potentially in the millions annually to the extent the measure results in changes to the number of abortions and live births, the analysis found.

Valid signatures from 585,407 registered voters — 8 percent of the total votes cast for governor in the 2014 general election — are required to qualify the measure for the ballot, according to Secretary of State Alex Padilla.

Similar measures were defeated in 2005, 2006 and 2008.

Padilla gave backers permission Monday to begin gathering signatures.