There are narrations in Hadith communities of Shia and Sunni Muslims that signifies marital relationship is disapproved (makr??). Some of times and situations in these narrations has been prohibited which some of them in term of significance are not stable and have anxiety. Among these narrations, many valid cases warn about sexual intercourse and declare that it is disapproved. In a lower frequency, copulation in the beginning and in the middle of month is forbidden too. In this essay with the aim of a deeper understanding of mentioned narrations, a new concept of this word is provided by philologist of “sha?r” (month) in Quranic verses. Furthermore, by employment of narrations and outcomes of medical sciences, a new hypothesis suggested that prohibiting sexual relations at the end of each month is a mandate for genesis generation increase and expansion of births.