NFP and Population Levels

Right now we have about 7 billion people on Earth, right? Suppose the entire world was Catholic, and followed NFP teachings and had a family of between 6 and 12 children. The median family size would be 9 children, or 4.5 per person currently living. In one generation, our planet’s population would go from 7 billion people to (7 x 4.5) 31.5 billion. Could we really support 31.5 billion people?

If this hypothetical rate of reproduction continued for two more generations, we would have 637 billion.

What is the basis for assuming that families would consist of 6 to 12 children? Is this even true of the current Catholic population?

This appears to be a baseless projection.

This is average for the conservative Catholic families I know.

Why is it that before the invention and proliferation of ABC the population did not skyrocket like that?

Mortality rates were much higher.

How many families is this? Is this a representative sample of the whole world? Why?

Looking around my parish of 1100 households, the average number of children is less than 6 per family.

What percentage of the families there follow the teachings on birth control?

Not all women are fertile enough or healthy enough to bear so many children, so I doubt that the average number of children would be so high as your estimate. Plus, you are not taking into account the fact that birth defects, diseases, and terminal illnesses impact the rate of population growth, too. Drought and famine also impact it.


Read the first post.

Right. I know plenty of NFP-using Catholics (myself included) that have less than 6 kids. The average is way less than 9.

Besides, if all 7 billion people were devout, NFP-practicing Catholics, you’d have to calculate in the fact that at least 4 out of those 9 children would pursue a religious vocation. :stuck_out_tongue:

I don’t see any reference to contraception, so it relevance is suspect.

The scenario assumes that no couple uses birth control to limit the size of their family.

Very good point! More Catholics would mean loads more religious vocations. So not everyone would be marrying and procreating. After all, not everyone marries and procreates now, right?

Also, I am approaching the end of my fertile years, and as a more fertile than average woman, I have only had four live births so far, and am expecting my fifth. It is highly unlikely that I will surpass 6. So, I would guess it is more rare to see such large families, but they would stand out. I bet there are tons of faithful Catholic couples who adhere to Church teachings on marriage and family planning, but they don’t stand out so much because their families are naturally smaller.

Not that much! Not enough to suggest a boom like your math suggests. That is not how population works. Mortality rates are 100 percent.

NFP is a method of birth control. It is being used, and has been used, to manage the size of families. There is no evidence that if all Catholic abandoned contraception that family sizes would jump significantly.

Infant mortality rates were higher, and the average lifespan of a person was much shorter. Even in 1910, the average lifespan of a man was 48, and for a woman, it was 51.

Then why did you reference NFP in your thread title?

In your scenario, do the couples use NFP to avoid pregnancy at all?

NFP is birth control? I thought it was to be used only to space pregnancies for grave reason, not to be used with a contraceptive mentality.

No contraceptive mentality was assumed, nor implied, by my post. I used “birth control” to simply mean the spacing of births. For a practicing Catholic, the method for this spacing control must be moral, i.e., abstinance or NFP.

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