The Associated Press reported Wednesday that well-to-do foreign families are traveling to the U.S. to gender-select embryos in an attempt to escape their own country’s ban on the practice. Critics call it “global tourism for designer babies” and say the U.S. needs to ban the practice as well. But doctors who practice embryo sex selection say they simply help to even out a family’s makeup. Dr. Jeffrey Steinberg, who works for the Fertility Institutes of Los Angeles and Las Vegas, has observed gender preferences from different countries. “The Chinese like boys. Canadians like girls. Every country is different,” he told the AP. And when considering all of his clients, preference for either males or females evens out, he said.

Opponents have jumped on the issue, saying that these doctors are pandering to the same gender bias that underpins female infanticide. Sure there’s some overlap, but gender preference and female infanticide are different issues; it would be a problematic philosophical jump to assume that families choosing to select male embryos would otherwise kill a female infant. Surely there are a whole host of motivations to gender-select embryos; included, sure, are sexist beliefs. But there are also cases like that of Robert and Joanna, who already have two boys and want to ensure that their third child will be a girl. They flew from Australia to visit Dr. Steinberg and have a female embryo implanted in Joanna’s uterus for the cost of half their yearly income.

Most interesting is to consider the possible social implications if these practices became widespread. Access to the procedure across economic and social strata would be a factor. But there’s no saying how gender preferences would play out: Would Canada end up with an overabundance of females and China with a dearth of them? Or would it just lead to more gender-balanced families? It seems a plot for a sci-fi novel, but it clearly it isn’t such a far-off reality.