Topeka ? A proposed amendment to the Kansas Constitution to ban abortion has been formally introduced by 25 state House members.

The lawmakers filed their proposed “personhood” amendment Wednesday.

The measure would amend the state constitution’s Bill of Rights to declare that Kansas guarantees the rights of every person, starting with fertilization of the human egg.

Critics say it’s broad enough to ban common birth control methods. Even some abortion opponents are wary of the proposal, fearing its enactment would lead to a lawsuit and unfavorable court decisions.

Two-thirds of both the House and Senate must approve the measure for it to go to a statewide vote. It would appear on the ballot in the August primary, when approval by a simple majority of voters would change the constitution.