The junta-era policy, described by activists as "abhorrent", has been reaffirmed in two townships, according to Win Myaing, spokesperson for the Rakhine government, in the wake of deadly religious unrest last year.
"Because the birth rate is so high in that area, a district order was imposed a long time ago to enforce monogamy and not to have more than two children. It was approved again (last week)," he told AFP.
Human Rights Watch has accused the authorities of being a party to ethnic cleansing over the violence, which killed some 200 people and saw mobs torch whole villages.
An official commission's report in April into the unrest suggested voluntary family planning to stem a high birthrate among the Rohingya that it said stoked tensions, as well as the short-term continuation of ethnic segregation in the state.
Local authorities have previously been accused of trying to restrict birthrates among the Rohingya by refusing to acknowledge any more than two children per married couple -- thereby denying them legal rights and access to services.
Human Rights Watch said local authorities, which mainly represent the Buddhist ethnic Rakhine, appeared to be using the official report to give credibility to a policy it described as "abhorrent, inhumane" and "completely contrary to human rights".