On the fortieth anniversary of the landmark abortion decision, Roe v. Wade, a new poll shows the majority of people under 30 can’t name what the case was about. Only 44 percent among those ages 18 to 29 know it dealt with abortion. In an attempt to help fill that knowledge gap, here are 9 things young people—and everyone else—should know about Roe:

1. Contrary to the popular conception, Roe does not limit abortion to the first trimester but institutionalized abortion on demand in all 50 states. As the Supreme Court wrote in the 1992 case Casey v. Planned Parenthood, “we reject the trimester framework, which we do not consider to be part of the essential holding of Roe.”

2. Another abortion case that was decided the same day as Roe was Doe v. Bolton. The Court’s opinion in Doe v. Bolton stated that a woman may obtain an abortion after viability, if necessary to protect her health. The Court defined “health” as follows:

Whether, in the words of the Georgia statute, “an abortion is necessary” is a professional judgment that the Georgia physician will be called upon to make routinely. We agree with the District Court, 319 F. Supp., at 1058, that the medical judgment may be exercised in the light of all factors – physical, emotional, psychological, familial, and the woman’s age – relevant to the well-being of the patient. All these factors may relate to health.

As Ramesh Ponnuru has explained,

The ‘attending physician’—in real life, very often an abortionist with a financial stake in the decision—can always say that in his medical judgment, the abortion was necessary to preserve the woman’s emotional ‘health,’ especially considered in light of her ‘familial’ situation. Any prosecution would have to be abandoned as unconstitutional. In other words: The Supreme Court has effectively forbidden any state from prohibiting abortion even in the final stages of abortion.

In the Roe decision Justice Harry Blackmun said that the two opinions—Roe and Doe—“of course, are to be read together.”

3. Even legal scholars who agree with legalized abortion have admitted that the reasoning in the Roe decision—which was written by Justice Blackmun—was shoddy. Edward Lazarus, a former clerk for Justice Blackmun, has written that, “. . . as a matter of constitutional interpretation and judicial method, Roe borders on the indefensible.” In 1973, law professor Laurence Tribe wrote in a Harvard law review article that, “One of the most curious things about Roe is that, behind its own verbal smokescreen, the substantive judgment on which it rests is nowhere to be found.”

4. The majority of American states were not moving toward liberal abortion laws before Roe. In 1971, on the eve of Roe, legislation to repeal abortion laws was voted down in Colorado, Massachusetts, Connecticut, Illinois, Iowa, Maine, Maryland, Minnesota, Montana, North Dakota, New Mexico, and Ohio.

5. Because of the Roe decision, America is (along with Canada) one of the only Western countries in offering no legal protection to the unborn at any stage of development.

6. In a 1971 resolution on abortion, the Southern Baptist Convention resolved that “society has a responsibility to affirm through the laws of the state a high view of the sanctity of human life, including fetal life.” However, the largest Protestant denomination in America had a peculiar definition of sanctity of human life, for the very next sentence called upon Southern Baptists to “work for legislation that will allow the possibility of abortion” under such conditions as ‘fetal deformity’ and ‘damage to the emotional, mental, and physical health of the mother.’ Three years later—and two years after Roe codified this position into law—the SBC reaffirmed the resolution. It wasn’t until 1980 that the SBC finally condemned abortion as a grave evil.

7. “Jane Roe” was the legal pseudonym for Norma McCorvey the plaintiff in Roe v. Wade. In the 1980s, McCorvey claimed she had been the “pawn” of two young and ambitious lawyers who were looking for a plaintiff with whom they could challenge the Texas state law prohibiting abortion. In the late-1990s, McCorvey was working at a Dallas abortion clinic when the anti-abortion group Operation Rescue moved its offices next door. She says Rev. Phillip Benham, Operation Rescue’s national director, started “sharing the Gospel of Jesus Christ” with her. She later became a Christian and committed pro-life advocate.

8. No one knows precisely how many illegal abortions there were before Roe, but in 1981 three researchers estimated a range from “a low of 39,000 (1950) to a high of 210,000 (1961) and a mean of 98,000 per year.” In 2009, 784,507 legal induced abortions were reported to the Centers for Disease Control from 48 reporting areas.

9. Slightly more than half (54%) of white evangelicals, according to the Pew Research Center study, favor completely overturning Roe. No other religious group, including white mainline Protestants, black Protestants, and white Catholics, agreed with completely overturning the ruling. In fact, substantial majorities of white Protestants (76%), black Protestants (65%), and white Catholics (63%) say the ruling should not be over turned, the survey found.