* engaging youth in various task eg building public property, exploring
*youth should accomplish certain task to get marriage which is popular in many other part of world to prove he is man now
*they could make an ritual for intercourse in certain time of year cause there were no contraceptives device ..making such ritual could help them
*its just hard to figure out other strategy ...why sacrifice human to controll birth they could simply multilate the genetical of victim of sacrifice ritual ...