Arizona, seemingly determined to take bad ideas and make them worse, is moving ahead with a bill that both makes explicit and codifies into law the current fights over contraception coverage. Arizona House Bill 2625, authored by Republican Debbie Lesko, allows employers with religious or moral objections to contraception to deny insurance coverage of it to their employees. This is in response to the Affordable Care Act’s provision that insurance be required to cover contraception without a co-pay; the Obama administration already made a compromise that should protect religious employees. Yet conservatives have had a hard time letting it go.

The interesting thing about Arizona’s bill, however, is that it does have an exception built in for women who don’t use birth control for sex. If it is for other medical reasons, employers are required to cover it. The tricky question is, How would anyone know the difference? The bill takes care of that conundrum by allowing employers to ask their workers for proof that their baby pills are not being used during baby making time. Some are speculating that this opens up the door to employers firing their employees because they’re on the pill.

Here’s the crazy thing: employers should want their employees to use birth control for reproductive purposes. As Annie Lowrey recently wrote, “A number of studies have shown that by allowing women to delay marriage and childbearing, the pill has also helped them invest in their skills and education, join the work force in greater numbers, move into higher-status and better-paying professions and make more money over all.”

She points to an influential study by Claudia Goldin and Lawrence F. Katz, which shows that the pill encouraged women to pursue careers by ensuring that their investments in education and training weren’t disrupted by unwanted pregnancy, as well as changing the marriage market so that career women could delay and be more attractive mates. “Because up-front, time-intensive career investments are difficult for women with child care responsibilities, the pill encouraged women’s careers by virtually eliminating the risk of pregnancy,” the authors write. On top of this, the pill importantly decoupled sex and marriage. That meant that the cost of delaying marriage went down, which made women with good career prospects more attractive as potential wives. Take that, Rick Santorum.

The results are crystal clear: after the pill became widely available and generally used, women flooded the workforce. In 1950, only 18 million women were in the workforce. By the 1980s, after contraception had not only become legal but the norm, 60 percent of women of reproductive age had a job. By 2000, the number of working women had more than tripled since the ’50s. All of this coincided with a falling birth rate: The rate in the 1950s and early 1960s was 118 births per 1,000 women aged 15-44; by 1980 it had fallen by almost 75 percent, dropping to sixty-eight births per 1,000 women. When women are freed up from unwanted pregnancy and able to control the pace of childbirth, they are that much more able and likely to hit the workforce.

Which is good news for employers and for the economy. Our economy would likely be 25 percent smaller than it is today if women hadn’t entered the workforce in droves, the consulting firm McKinsey estimates. More workers—and ones that are better trained and educated—is really good news for employers. In fact, businesses have lately been complaining that a lack of skilled workers is threatening their productivity. Can you imagine if they were still only able to dip into half of the population when seeking employees?

Supposedly moral objections to giving women control over their reproduction aside, contraception makes acute business sense. Who would want to opt out of that?