It was a momentous vote for the United Methodist Church, as the future of the country’s second-largest Protestant church hung in the balance. In a former football stadium in St. Louis last month, church officials and lay leaders from around the world voted to strengthen their ban on same-sex marriage and gay clergy, a decision that could now split the church.

But at least four ballots were cast by individuals who were not authorized to vote, according to interviews and a review of the church’s records. The individuals were from African delegations whose votes were critical to restricting the church’s rules on homosexuality.

The final 54-vote margin against gay clergy and same-sex marriage exceeds the number of unauthorized votes discovered so far. But the voting irregularities raised questions about the process behind the divisive decision, which devastated progressive members. Some have discussed leaving the denomination and possibly creating a new alliance for gay-friendly churches.

Church leaders are now discussing whether new votes should be called, Bishop Thomas J. Bickerton, who serves on the commission on the general conference, said in a phone interview.