As the U.S. Supreme Court prepares to rule on New Hampshire's parental-notification law, an increasing number of states are requiring parents to be involved when their teenage daughter considers abortion.

In all, 34 states now enforce parental notification or consent laws. Florida, Ohio, and Oklahoma each passed such laws in 2005. The statutes require minors to include their parents in the decision—Ohio requires parental consent, while Florida and Oklahoma mandate only notification.

All three states allow judges to bypass the law, while Florida and Oklahoma also permit doctors to perform abortions during medical emergencies.

The increase is partly due to a deliberate effort by right-to-life leaders. "The strategy is to do this state by state," John Whitehead, president of the Rutherford Institute, told CT. Mary Balch, director of state legislation for National Right to Life, said the remaining 16 states that don't require parental involvement represent "the last frontier." Among those is California, whose voters on November 8 narrowly rejected a proposed parental-notification law.

Nine states that passed such laws have not yet enforced them. New Hampshire's suspended 2003 statute provides the basis for Ayotte v. Planned Parenthood, which went before the Supreme Court on November 30. Opposing sides in that case debated whether parents should be notified when their daughter is facing medical complications or only when their daughter's life is in danger. They also argued about whether the parents of a girl younger than 18 must be notified at least 48 hours in advance of the abortion.

It is unclear how a ruling either way would affect similar laws. If the Supreme Court upholds the lower court's decision to invalidate New Hampshire's ...