"I wish that people would enter their reproductive age when they are 15 and finish it when they're 19. I wish that no matter whether they are a boy or a girl people would start their puberty at the age of 13 and then reach their full sexual maturity at the age of 15 (the start of the new reproductive age). By 'full sexual maturity' I mean the stage of sexual development people reached at the age of 20 before the wish.
I wish that even though they were already sexually matured at the beginning four years of their reproductive age they would still keep developing (overly), increasing the significance of their primary and secondary sexual characteristics.
I wish that once people reached 19 they would begin a 1-year-long phase of 'un-puberty' when they would loose all the previously gained sexuality and eventually become infertile. They will remain adults though, just without the possibility and the instinct for procreation, with androgynous looks completely devoid of any sexual characteristics.
I wish that this would lead to all the responsibility for procreation of human race to be on the teenagers. That means that firstly it will be absolutely normal for teenagers to have sex whenever and wherever they wanted. Sex wouldn't be a taboo anymore as well; On quite contrary - polygamy, incest and frequent intercourse in a varieties of ways would be encouraged (not really that they will need to be as peoples libido as a sexual characteristic will also overdevelop over the four years of the reproductive age). I wish there were no STDs as well.
Also, I wish that in order to keep the population levels stable, the fertility levels would be stellar and there would be no sort of contraceptives in use. That would result all the girls being pregnant virtually all the time, save for the short one-week period of infertility after they give the birth to a baby.
I wish that when people would be in their reproductive age they wouldn't have to care for their children, their grandparents would do it for them instead. The only duty they would have towards the children will be for girls to supply their breast milk for feeding the babies.
Additionally I wish the girls were extra flexible and had their vaginas improved when they would be pregnant so that they could keep having sex on a daily basis without any risk of miscarriage.
Just for the fun of it, I wish it were physically impossible for a girl to disobey a guy's order. I wish the orders not to influence a girl mentally in any way, the orders would just somehow make the girl's body to act on its own fulfilling the guy's command. Of course for most of the time the girls won't mind the boys wanting to have sex with them (girls will be willing because of their increased libidos). The last wish is there just to make sure that it's the males who really choose how and when everything happens.
Finally I wish the wish to have some one random additional effect which is going to make the experience more interesting, especially for me..."