Research connects reduced fertility rates to decline in manufacturing jobs

A sociology researcher at UW-Madison has found a connection between reduced fertility rates and a decline in manufacturing jobs on the national level.

“Metro areas that experienced steeper declines in goods-producing businesses were more likely to experience steeper declines in fertility rates,” said Nathan Seltzer, whose work was published last week in the journal Demography.

His research involved analyzing every birth in the United States at the county level over a period of 24 years. He found fertility rates for metro areas could be better predicted by the area’s share of businesses in manufacturing industries than by its unemployment rate.

The link between manufacturing jobs and fertility rates was especially strong for Hispanic women, who are more likely to work in goods-producing industries than women of other ethnic groups, according to the study. Still, manufacturing business activity was more closely tied to fertility than the unemployment rate for all ethnic groups.

“These structural trends are driving this increased financial precarity and influencing women and couple’s decisions to have children,” said Seltzer, a doctoral candidate in the sociology department.

The study included birth data from all 381 Census Bureau-designated metro areas between 1991 and 2014, which contain roughly 85 percent of the U.S. population.

He used a measure called the total fertility rate, or TFR, which calculates how many children the average woman would have in her lifetime based on current birth rates.

In the 24 years he analyzed, goods-producing businesses fell from 18.3 percent of all U.S. companies to 14.2 percent. He connected that decline to an overall decline in TFR.

In a narrower timeframe, between 2006 and 2014, the number of U.S. manufacturing businesses fell by 2.4 percent. At the same time, Hispanic women’s fertility fell 24 percent, while all other groups had a fertility decline of between 7 and 8 percent.

Although the change in unemployment rate did help explain declines in fertility, Seltzer found the loss of manufacturing businesses was more significant.

“Once you account for the share of goods-producing businesses in an area, you find that it better explains declines in fertility than the unemployment rate does,” he said.