maybe so but it is more effective for of birth control,
think about it one man can in theroy inpregnate a girl a day for 9 months, over this peroid a woman can only have one child. but if there are a lot of women then there are going to be a lot more childern if u have 100 women and 75 men, all 100 women get pregnate that thats 100 babies rather than 75. i don't really strongly agree with this but china and india are the only countries right now with 0 or - birth rate, in which all countries are going to have to reach before to much longer