The endless conversation about when women should start having babies is going on now on the New York Times's Room for Debate blog, with various thinkers weighing in on the pros and cons of delaying, rushing, adopting, and otherwise deciding whether and when to have children. The exchange was provoked this time by an article in this month's Atlantic by Jean Twenge, a psychologist at San Diego State University, who says that the conventional wisdom about a serious drop in fertility after age 35 is just plain wrong.
I'm not quite sure what to make of the article by Twenge, who's known primarily as the nation's most forceful proponent of the notion that Millennials are the most narcissistic set of young people we've ever seen. I'm still waiting for an expert to weigh in on whether her re-analysis of available fertility statistics makes any sense, and whether she's right that all the frenzy about women's fast-ticking biological clock is overblown (though my friend and fellow PT blogger Paul Raeburn, who's a science media critic rather than a scientist, did just write an interesting assessment that concluded that Twenge's piece is "right on target"). But I did want to mention one interesting finding to toss into the debate, something my daughter Samantha and I described in our book Twentysomething—a real economic benefit to women who delayed childbearing. It's from a study conducted by Amalia Miller, an economist at the University of Virginia, who found that for college-educated women in professional and managerial jobs, every year of delaying pregnancy means a significant bump in wages, hours worked, and total lifetime earnings.
Miller made an "opportunity cost" evaluation of choosing motherhood over career by imagining a hypothetical woman who steps out of an upwardly mobile career for one year to have a baby. This woman's "wage profile," the slope by which wages increase over time, will flatten even after she returns to a comparable job following that year at home. If the flattening begins when this hypothetical woman is 30, it starts from a higher wage than if it begins when she's 23. "Women can achieve higher earnings by delaying motherhood during their twenties and early thirties," Miller concluded. For every year a woman puts off having a baby, she wrote, her wages increase by 3 percent and her lifetime earnings increase by 9 percent. In other words, a woman who has her first baby at 34 will, on average, have lifetime earnings 72 percent higher than a woman who has her first baby at 26.
That opportunity cost seemed so high that I contacted Miller by email to make sure I had gotten the numbers right. Yes, she assured me, waiting eight years yields, on average, 72 percent more in lifetime earnings. Another way of looking at it, she wrote, is that a delay of ten years in having your first child will double your lifetime earnings.
I asked Miller if her findings had affected her own personal decisions about childbearing. When we communicated about a year ago, she was 35 years old and didn't have children yet. "I think that my career is in better shape now than it would have been if I’d had a child in my twenties or even early thirties, though of course, I can’t prove that or even know for sure," she wrote in an email. "This may not be true for everyone, but my personal experience does seem to fit the general pattern in the data that I found in my study that there is a tradeoff between early motherhood and career outcomes."
All decisions involve tradeoffs, of course. It's just eye-opening to see these particular tradeoffs laid out so starkly in terms of dollars and cents.
Adapted in part from Twentysomething: Why Do Young Adults Seem Stuck? by Robin Marantz Henig and Samantha Henig, out in paperback in August 2013.