Contraception or…
Women have an average of 30 years in which they can give birth, let us say that given no contraception and every [non medical interference] effort is made to concieve, the average amount of children produced would be a conservative estimate of 20. If you disagree then half the equations at 10 births on average. To decide upon the universal rule, we must assume that everyone goes by the ethic of not using contraception, as there is little point in having an ethic if you don’t expect people to go by it, and this is a debate concerning the application of said ethic…
Now the math;
There are currently 6 billion people on the planet approx, approximately half are female, so every time that half of the population gives birth the number is increased by 50%. Now multiply that by 20, so we get 3 X 20 = 60 billions of people in a single generation! [or 30 billions if the average birth is considered as a round 10]. Now the multiple is 60/2 = 30 X 20 = 600 billions of people on the planet. The next multiple is then 600/2 = 300 X 20 = 6000 billions of people on the planet.
*All lesser estimates are simply smaller multiples yet all above two quickly become large numbers e.g. 6 [billions of people] X 4 = 24 billions in a single generation. Then 24/2 =12 X 4 = 48, then 48/2 = 24 then 24 X 4 = 96 billions of people. So even with a low level of birth the population would still go up considerably.
The only counterbalance we have is infertility [which is counteracted somewhat by modern treatments], disease and accidental death. We have to also consider that the percentage of such deaths or lack of births [infertility] must occur before or during the cycle of births, disease, infertility and death by accident has no effect whatsoever on the birth rate after that.
We may also consider that life expectancy is going up and the age at which mothers can give birth is also going up, which only add to the numbers of people on the planet at any one time.
In short there is no way that non-contraception ethics are viable unless a chosen few go by the ethic. Then you have the moral dilemma whereby that proportion of the population grow at a greater rate then those who don’t go by the ethic. Eventually they would be by far the majority of the populous, growing exponentially in increments relative to the size of the group. Whatever the initial size is, the end result would be the same, the group with the advantage would over run the remainder of humanity and we would be left in a similar situation as in the scenario whereby everyone goes by the ethic.
If ever there was a moral absolute, then given the limits involved, the ethic of using contraception far outweighs the ethic of not using it, and in extreme measure.
Just for fun lets take the ethic to its furthest extreme, I find such craziness kinda makes it clear just how insane some ethics are.
Eventually, given that we find ways to feed people, there would be so many people that the entire earths surface would be covered in humans, each standing next to one another. Presumably each persons space would have its own toilet and feeding tubes etc, perhaps coming from intense fish farms in the worlds oceans [as all the land is occupied by people].
Moral dilemmas; I would presume that people who don’t believe in contraception would usually not believe in having sex in public spaces [there are no private spaces left].
Next level of insanity; when all these people have a child, we then have to decide who will stand on who’s heads?
Then with each 2 births we get another layer of people on top of the previous layer, either crushing down on the ones below or some kind of construction [layered containers] would be implemented.
Eventually you get too high for breathable air [too many layers of people], so lets imagine that a way is devised that air is created and transported by tubes to the upper levels, so that the process may continue. Eventually there would be so many levels that people would have to duck as the moon comes around, after a point there are so many people that the moon has to be destroyed or sent out into space…
To cut a long story short, eventually the numbers reach a critical mass and implode into a black hole or a sun [not sure there lols]. So in the end humanity can only possible destroy itself completely if they go by the ethic of not using contraception.