Bishops attending a Vatican meeting on ministering to young Catholics are being confronted about why no women participants can vote on the final proposals that will be prepared for Pope Francis.

A petition sponsored by a half-dozen progressive Catholic lay groups demanding voting rights for the handful of nuns attending the month-long synod had received nearly 5,000 signatures as of Monday.

A related social media campaign inspired Benedictine nuns in Switzerland to post photos of themselves holding #votesforcatholicwomen signs.

At nearly every Vatican press conference since the synod began on October 3, journalists or activists have asked the bishops to explain why two non-ordained religious brothers will be able to vote alongside bishops, but not women religious superiors.

The bishops generally respond by saying Vatican rules do not allow it.