Smartphones linked to sharp drop in US birth rates, study finds

A recent episode of JTBC's "Divorce Contemplation Camp" featured a story about a husband so absorbed in gaming that he checked his smartphone even during sex.

The anecdote has taken on new resonance in light of research suggesting that the spread of smartphones is one of the drivers behind the sharp decline in birth rates — by weakening face-to-face relationships and reducing the frequency of sexual activity.

According to US media reports on Friday, a research team from Middlebury College and the National Bureau of Economic Research (NBER) identified 2007 as a critical inflection point for US birth rates in a recently published NBER working paper. That year, Apple's Steve Jobs unveiled the first iPhone.

From 2007 to the present, the US general fertility rate — the number of births per 1,000 women of childbearing age — has fallen by roughly 22 percent.

The researchers found that economic conditions, contraceptive use, and the cost of housing and child care did not easily account for the decline, and turned their attention to the potential impact of the smartphone's rapid adoption.

The team noted that between 2007 and 2011, the iPhone was available in the United States exclusively through AT&T's network. They compared birth rate trends in areas where AT&T's mobile broadband network was built out early against those where it was deployed later. Areas where more than 90 percent of residents had early access to the iPhone saw a significantly steeper drop in birth rates than areas where network coverage remained below 10 percent.

The gap was especially pronounced among teenagers and young adults. Among 15-to-19-year-olds, birth rates fell 14 percent in areas with low smartphone penetration but 26 percent in high-penetration areas. Among those in their 20s, the decline was 10 percent in low-penetration areas and 15 percent in high-penetration areas.

The researchers estimated that early smartphone adoption accounts for 33 to 52 percent of the decline in the US general fertility rate between 2007 and 2011.

The team raised the possibility that smartphones served as a substitute for physical contact and in-person interaction.

The researchers also cited survey data showing that the iPhone reduced face-to-face interaction, increased consumption of online pornography, and lowered the frequency of sexual activity.

Caitlin Myers, the lead author of the report and an economist, said the research carries policy significance. "I worry that we don't really understand why fertility is falling and that we're looking in the wrong places," she said, adding that "the answer may lie in how policymakers can promote human face-to-face interaction going forward."