Washington ? Same-sex marriage proponents have introduced a ballot measure that would require heterosexual couples to have a child within three years or have their marriages annulled.

The paperwork for the measure was submitted last month in Olympia. Supporters must gather at least 224,800 signatures by July 6 to put it on the November ballot.

The Washington Defense of Marriage Alliance hopes the idea prompts “discussion about the many misguided assumptions” underlying a state Supreme Court ruling that upheld a ban on same-sex marriage.

The proposed ballot measure would require couples to prove they can have children to get a marriage license. Couples who do not have children within three years could have their marriages annulled.

All other marriages would be defined as “unrecognized,” making those couples ineligible for marriage benefits.