Legal marriage age should be 15 or?

As soon as someone hits puberty. They are able to have sex and should be allowed to have with certain someone. I mean many kids are already are sexually active by age of 16.... But most won't stay with that person. But having people of that age marrying will not only stop sex culture but also make them more sexually responsible, as to whom they commit themselves if they do. Scientifically if a girl starts to have sex late on life even at age of lets say 19 she will have troubles teaching full orgasm. Because after puberty girl enders into a period where nerves start to grow down there that would provide pleasure during sex but lack of activation causes them to not reach their prime during the period of fastest growth. I fully understand there are economical dilemmas associated with it but its a system thats at fault. Person should be able to provide for oneself before age of 24, there shouldn't be so much inflation. Anyways many teenage problems can be solved. Cheating, random sex, outcast, games, etc.