Poking around Google Data Explorer I reacquainted myself with an interesting fact: though the teen birth rate in Bangladesh is greater than that in Pakistan, the total fertility rate is far lower. The disjunction has emerged over the last generation, as Bangladesh's TFR has dropped much faster than Pakistan's. To the left you see a scatter plot, which shows teen fertility rates (age 15-19) as a function of total fertility rates. I've labeled a few nations, and also added the color coding by region. It is notable that the nations above the trend line seem to be Latin American, while those below are disproportionately Middle Eastern. That means that Latin American nations have higher teen fertility in relation to their total fertility, while Middle Eastern nations have lower teen fertility in relation to their total fertility. Sweden actually has a rather high fertility rate in relation to its teen birth rate. The expectation is generated by world wide patterns, so I thought I'd look more closely at the original data sets from the The World Bank. All the data is from 2008. The teen birth rates are per 1,000 of teens in the age range, with TFR's are per woman.
My contention is this: those nations with high overall fertility despite low teen fertility rates indicate an ideological or operational pro-natalist cultural stance. That means that mature adult women in marriages are presumably having many children. The high teen fertility rates in Bangladesh vis-a-vis Pakistan is probably simply due to lower aggregate development (Pakistan is still higher up on the HDI ranking, though the gap is closing).
Below are some charts. First, a plot with lines of best fit (as generated by R's loess function). Then, absolute deviations from the line of best fit as a function of fertility. Also, percentage deviations from the line of best fit as a function of fertility. I provide the weighted trend line, but rely on the unweighted fit for the rest of the charts.
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Next, let's compare percentage and absolute deviation from the trend line on the same plot.
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Finally, a table with the "top 15."
To restate: my assertion is that nations with a high TFR despite low birth rates in the 15-19 age range indicate a realized preference for large families. This seems to be the class that Israel, Rwanda, and many Middle Eastern nations fall into. Some European nations, such as France, have a higher TFR in relation to what they're teen birth rates would predict. This is just a function partly of very low teen birth rates. But in the case of France it is probably a function of moderate pro-natalism.
In the other class you have many Latin American nations, whose fertility is modest, but teen birth rates are very high. I think this is probably a symptom of demographic structure within the population. There's a lot of inequality and variation in economics and cultures within the societies. I think this is why a very low TFR countries such as Romania shows up: the Roma minority has a high teen birth rate. They are not numerous enough to change the average TFR much, but have shifted the teen birth rates.
