Happy Contraception Day! Today’s the day that most insurance plans in the United States have to start covering birth control with no co-pays under the Affordable Care Act. As a woman who’s spent a fair amount of effort and money avoiding motherhood, I couldn’t be more pleased.  Birth control can be very expensive, and laws that help increase access are a great thing in my book.

But you don’t have to be a woman of a certain (reproductive) age to benefit from expanded access to contraception. Contraception is good for the women you care about, their families, their communities and the planet. And who could possibly be against that? (Well, plenty of people, but I’ll touch on that later.)

First up: Women. It’s not just the childless by choice who benefit from contraception. Birth control allows women to wait to have babies until they’re ready. When women can plan and appropriately space their pregnancies, they and their babies are healthier. According to the reproductive health gurus at the Guttmacher Institute, “Women whose pregnancies are planned are more likely to receive timely prenatal care. They are less likely to smoke or drink during pregnancy, and more likely to breast-feed once their baby is born.” That’s good stuff.

The typical American woman only wants two children. Contraception allows families to have the number of children they’re comfortable raising–and give those children the best possible shot at success. A child who’s received good health care and a great education is more likely to grow up to be a productive member of society. That helps entire nations succeed–and in our complex, interconnected global economy, we need as much success as we can get.

So how does contraception help the planet? In a number: 26.8 billion. That’s how many people the United Nations projects will be sharing Earth in 2100 if we don’t slow population growth rates. Keep in mind that we have about 7.1 billion people on the planet right now. Picture nearly four times as many people struggling to find (and afford) water, food, and energy on a planet where water, food and energy are already scarce in many areas. It’s a recipe for disaster, but it’s an entirely preventable disaster if we take action.

By Guttmacher’s projections, 222 million women in the developing world don’t have access to affordable and appropriate contraception. Here in the United States, nearly half of all pregnancies are unplanned. By expanding access both here (thanks, President Obama!) and abroad (thanks, Melinda Gates, UNFPA, USAID and friends!), we can reduce unintended births, slow down population growth and give the people of 2100 a little more breathing room.

Sounds great, right? Not to everyone, unfortunately. The tentacles of sexism are long and tightly wrapped around societies – including ours. The collective right-wing freakout over the Affordable Care Act’s contraception mandate is only the latest example. While many of us see women’s equality as an inalienable right, powerful interests see it as a threat. That’s why we can’t rest. We have to keep fighting the forces that would be happy to see all women barefoot and pregnant and confined to making sandwiches in the world’s kitchens.

The Affordable Care Act’s contraception coverage is a great step in the right direction, and it will help women. And men. And communities. And right-wingers, even though they claim otherwise. And our planet. And the people of 2100. Here’s hoping the long fight for gender equity is done by then.

Amy Phillips Bursch is the media relations manager for Population Connection, the nation’s largest grassroots population organization. You can contact her at [email protected].