(The Sanger Papers/New York University)
(The Sanger Papers/New York University)

One hundred years ago last Sunday, nurse Margaret Sanger opened the nation's first birth control clinic on Amboy Street in Brooklyn. For a 10-cent fee, visitors were given a pamphlet — “What Every Girl Should Know" — and a tutorial on the female reproductive system and how to use various contraceptives, according to a New York University project about Sanger’s legacy.

That clinic eventually evolved into Planned Parenthood, a nonprofit organization that is credited with making reproductive health a priority for all and that treats millions of people in its clinics each year. Women — and men — now have access to all manner of birth control, including implantable devices and shots in addition to the pill and condoms. And the passage of the Affordable Care Act means insurers must cover it.

With Planned Parenthood in the spotlight this year as Congress and state legislatures fight over its funding, it’s a good time to look at how far we’ve come in the past century regarding contraception. Here are four surprising things about where the United States stands on the issue today:

1) The pill remains the most popular method of birth control for women, with 25 percent of those who practice contraception using it. It’s most popular among white women, teenagers, young adults and college graduates. An additional 15 percent use condoms, and 10 percent use intrauterine devices (IUDs), which are sold under brand names such as Mirena, Skyla and Liletta.

(Guttmacher Institute)

2) A large percentage of women (25 percent) and a significant percentage of men (8 percent) undergo sterilization. Those who do so are more likely to be poor, less educated, 35 or older, or living outside metropolitan areas. In 2012, 9.4 million women had tubal sterilization and 3 million men had vasectomies, according to the Guttmacher Institute‎, a research and policy nonprofit that focuses on reproductive health.

Protesters rally in front of the Supreme Court in March 2015 as the court heard oral arguments on the requirement that businesses provide female employees with health insurance that includes access to contraceptives. (Charles Dharapak/Associated Press)

3) More and more women are taking the pill for reasons other than birth control, especially menstrual pain and menstrual regulation. You may have heard a lot about premenstrual dysphoric disorder, or PMDD, in recent years. In 2013, it was added as a depressive disorder in the Diagnostic and Statistical Manual of Mental Disorders. Although it’s typically treated with antidepressants, some doctors also recommend birth control pills, and one brand, Yaz, is approved by the Food and Drug Administration for that purpose.

(Guttmacher Institute)

4) Despite the diversity and widespread availability of birth control in the United States, many partners still use the withdrawal method to try to avoid pregnancy. In a study published in the journal Contraception in 2014, researchers reported that among women at risk of unintended pregnancy, 13 percent said that withdrawal was “the most effective method” used in the past 30 days and that 33 percent had used withdrawal at least once in that period. Instead of seeing this as a concern, given that withdrawal is one of the least effective methods of birth control, the study authors suggested that this option could be seen as a secondary or backup measure to more-reliable forms of birth control. “Health-care providers who discuss contraception should include withdrawal in these conversations.  . . . If dual use were more widespread, it could help reduce the incidence of unintended pregnancy,” they concluded.

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