The organization had announced last week that it was considering allowing Scout troops to decide whether to allow gay membership, ensuring that the executive board meeting would be in the national spotlight.
Learning that a decision would be deferred, gay-rights leaders assailed the BSA.
"Every day that the Boy Scouts of America delay action is another day that discrimination prevails," said Chad Griffin, president of the Human Rights Campaign. "Young Americans, gay and straight, are hurt by the inaction associated with today's news."
"A Scout is supposed to be brave, and the Boy Scouts failed to be brave today," said Jennifer Tyrrell, an Ohio mother ousted as a den leader of her son's Cub Scout pack because she's a lesbian.
"They failed us yet again," she told The Associated Press. "Putting this off until May only ensures other gay kids and gay parents are discarded."
Tyrrell was among several current and former Scouts and supporters who rallied outside BSA national headquarters Monday and delivered petitions opposing the policy.
Conservative leaders made clear they would keep pressure on the BSA ahead of the May meeting.
Tony Perkins of the Family Research Council said his group would continue warning the BSA "about the grave consequences that would result if they were to compromise their moral standards in the face of threats from corporate elites and homosexual activists."
About 70 percent of all Scout units are sponsored by religious denominations, including many by conservative faiths that have supported the ban, including the Roman Catholic Church, the Southern Baptist Convention and the Mormon church.
The delay was welcomed by Southern Baptist leaders, some of whom had said they would urge their churches to seek alternatives to the Boy Scouts if the ban were eliminated.