A method, apparatus and computer program product are provided for facilitating transmission of data. A method and apparatus may detect one or more items of data that were transmitted with at least one error or unsuccessfully delivered to a device. The method and apparatus may enable retransmission of the items of data in at least one transport block. The method and apparatus may enable transmission of one or more items of new data in the at least one transport block such that a size of the new data does not exceed a variable size limit of a transport block size. The variable size limit may be dependent on one or more sizes of one or more transport blocks. The method and apparatus may determine that the variable size limit comprises a size smaller than a size of the at least one transport block.