Malekith believes that the gender of the Firstborn sorcerer is extremely important to the prophecy.
Malekith is also incredibly fallible, and his attempt to deny the prophecy by killing male sorcerers is exactly the sort of irony that is going to get him killed.
Malekith is also incredibly fallible, and his attempt to deny the prophecy by killing male sorcerers is exactly the sort of irony that is going to get him killed.