Age is a partial factor in the reproductive status of leos. I have had females at 6+ months begin producing eggs without introduction to males (obviuosly), so long as they are healthy and well cared for they mature rather quickly. They key to breeding any animal is their health. I would say that most of my males have been 9 months+. I do not for by weight either, since each gecko is built differently (ie.longer, shorter, wider, thinner)
Julie