Common sense dictates that people are happy when they are doing what they want to do ( in fact the statement is almost tautolgoical). In my view, what people want to do is influenced by what their culture tells them is worthy of pursuit, and unfortunately American society is telling women of all types that stay-at-home mothers are brood mares, while Hillary Clinton is what it's all about.Probably the most obvious of those things associated with both fertility and happiness is marital status. Among married women aged 30 and over (so those considered have had time to start a family and also to avoid shotgun weddings that presumably do not provide optimal happiness), the childless report the highest level of happiness. With the exception of a slight bump in going from one child to two, as the number of offspring increases, happiness decreases.
Instead of suggesting that making babies is linked to happiness, I should just try to prod people into matrimony. Once that stage has been reached, procreation is 45% more likely than among those who are not married*. Lead a mare to water and she's more likely to drink than if you just leave her in the desert. Of course, a comparison of married and unmarried women is not apples-to-apples either, but most women can find marriage partners if they are willing to.
Also, the ebbing of time influences how barren and procreative women see their own levels of personal contentment. The happiness index for married women who have 2-4 children and those who have not had any, by age group:
|Age||2-4 kids||No kids|
To the extent that any speculation can be made, women who have had children seem to be happier once the children are out on their own relative to peers who never had any kids. Even though the variances are small, happiness moves in opposite directions for those who've had children and those who have not had them. Psychologically, that's noteworthy. With children, your best days still probably lay ahead. Without them, growing old looks drearier.
* Among married women 30 years and older, only 13% of respondents did not have any children. For those of the same age who were not married, 40% were barren.