In the early 1950s, nurse and activist Margaret Sanger met with researcher Gregory Pincus to begin a decade-long quest to transform birth control. With the help of Katharine McCormick, a wealthy widow and suffragist, and Catholic OB-GYN John Rock, they revolutionized reproductive science, according to journalist and author Jonathan Eig. In his new book “The Birth of the Pill: How Four Crusaders Reinvented Sex and Launched a Revolution,” Eig chronicles their journey, exploring the origins of the first combined oral birth control pill. Eig recently spoke with U.S. News about the pill’s initial impact and its controversial implications today. Excerpts:

Jonathan Eig

What inspired you to write this book?

I had heard a sermon in a synagogue, where the rabbi made the case that birth control was arguably the most important invention of the 20th century. At first, my reaction was that it couldn’t be true, that there must be other inventions more important. Then it struck me that I had no idea where the pill had come from, how it had been invented and that most people really knew nothing of its origin. I began reading and learning more about it, and the story that I discovered was remarkable. It was this group of outsiders, these renegades really, who were trying to do something that by all accounts should have been impossible at the time.

What is the history of birth control?

People have been trying to control birth since the dawn of sex. As long as we’ve been trying to make babies, we’ve been trying not to make babies. You can go over thousands of years of the history of birth control, but by 1950, when these characters came along and began working on the pill, there were options, but there were no good options. The pill [represented] a huge change in the history of birth control because it gave women something reliable for the first time, something they could get and take on their own without the participation of men. That changed the dynamics of the workforce, it changed the dynamics of the family, and it changed our relationships with birth control.

Why specifically did the introduction of the birth control pill change the dynamics of the workforce?

When word began to get out that there was a possibility of a birth control pill, the response from American women was overwhelming. There were not very many women in the workforce because they were all staying home and taking care of their families. It was very difficult for women to even think about being treated like equals to men as long as they had the responsibility to take care of these large families. Birth control launched a revolution in that it freed women to pursue more options.

How has the Catholic Church responded to birth control?

It’s interesting to me that the Catholic Church really considered accepting the pill for a while. The argument was that it was really just an extension of the rhythm method, that it was a matter of timing. The pope at the last minute decided it didn’t work, and he wasn’t going to support it. You can only wonder what would have happened if the Vatican had approved the birth control pill back then.

Do you see the church’s stance changing in the near future?

We may get some signs very soon. The Vatican is holding a series of meetings right now to discuss family matters and there’s a lot of speculation about what kind of new things might come out of the church, but there’s no way to know. It’s a long and complicated relationship between the church and birth control.

What are your thoughts on the recent Supreme Court decision in the Hobby Lobby case and its implications for women?

I think it’s sad that we are in many ways back to the logic of 150 years ago that said that controlling reproduction is somehow immoral. Some people seem to think that women should only have sex when they want to have a child, and nobody says the same thing for men.

How do you see birth control playing out politically over the next few years?

I suspect that we will continue to fight over it. You can only wonder why male politicians in particular feel like they should have a say over what women do with their bodies. I think that it’s clear that when we have greater access to birth control, we see all kinds of good things happen. We see healthier women. We see healthier babies. We see fewer teen pregnancies, and we see fewer abortions. It seems to me that liberals and conservatives, Democrats and Republicans, ought to agree that access to birth control is a good thing.

What do you hope readers take away from your book?