A fetus is not a ``person'' with rights under the 14th Amendment to the Constitution.
A constitutional right to privacy exists and covers the decision of a woman to have an abortion in the first trimester (three months) of pregnancy.
To restrict abortion during the first trimester, government must show a ``compelling interest.'' This standard is called ``strict scrutiny.''
In the second trimester, the government could set some restrictions on abortion to protect the health of the pregnant woman.
In the third and final trimester, when the fetus is ``viable'' - able to live outside the womb - the government may prohibit abortions to save the life of the child. But if a woman's life or health is in danger, the woman's right to choose abortion takes precedence.
The Supreme Court's 1992 Casey decision did not overturn Roe v. Wade, but does allow states much more leeway to restrict abortion. Those who oppose restrictions now must prove that the barriers present an ``undue burden'' to a woman seeking abortion.
In line with this ruling, many states have added 24-hour waiting periods, mandated counseling on ``alternatives'' to abortion and required minors to get parental permission for an abortion.
* Since the U.S. Supreme Court decided 25 years ago today that women have a constitutional right to choose abortion, we have seen startling changes in medicine and technology, politics, culture, and gender roles. This is not mere coincidence. Abortion is one of the defining issues of the 20th century, encompassing questions of religion, life, sexuality and women's rights.
The fight over abortion has changed attitudes, and attitudes have changed the fight over abortion. Yet the most constant attitude remains ambivalence. Here is a chronology of highlights.
1960 - Birth control pill developed.
1962 - Unprecedented public debate of abortion after Sherry Finkbine, host of ``Romper Room'' TV show for preschoolers in Arizona, travels to Sweden for a legal abortion. Finkbine's physician had prescribed thalidomide for morning sickness; later, it's learned that the drug causes birth defects.
1965 - U.S. Supreme Court overturns a Connecticut law that made it illegal to dispense birth control information, saying that a constitutional ``right to privacy'' encompasses the right of married persons to use contraceptives.
1969 - American Medical Association policy describes abortion as a ``private matter between a woman and her doctor.'' U.S. Centers for Disease Control reported 12,417 legal abortions in the nation for the year. Illegal abortions estimated by others at 200,000 to 1.2 million a year.
1970 - New York, Hawaii, Alaska and Washington legalize abortion. More than 10,000 Pennsylvania women travel to New York for abortions.
CDC counts 193,491 legal abortions nationwide for the year.
1971 - Birthright, a program offering a ``positive alternative'' to pregnant women, is introduced in New York. Maternity deaths in New York down 68 percent in year since abortion legalized.
Pennsylvania abortion law: ''Whoever, with intent to procure the miscarriage of any woman, unlawfully administers to her any poison, drug or substance or unlawfully uses any instrument or other means with the like intent is guilty of felony, and upon conviction thereof, shall be sentenced to pay a fine not exceeding $3,000 or undergo imprisonment by separate or solitary confinement at labor not exceeding five years or both.''
1972 - The U.S. Supreme Court holds in Eisenstadt vs. Baird that constitutional ``right to privacy'' protects access to contraceptives for the married and unmarried alike. 1973 - Roe v. Wade and Doe v. Bolton decided by 7-to-2 vote of U.S. Supreme Court. Roe invalidates all state laws that prohibit abortion, determining that a constitutional right of privacy encompasses a woman's decision to abort a fetus in the first three months of pregnancy. The ruling is denounced by some religious groups, including Roman Catholic bishops. According to CDC, 615,831 abortions performed.
1974 - On the first anniversary of the Roe decision, ``right to life'' groups send 22,000 red roses to Congress. A red rose is a symbol of the anti-abortion rights movement, which calls itself Pro Life. Those in favor of abortion rights call themselves Pro Choice.
1975 - Abortions available in 33 of Pennsylvania's 67 counties.
1975 - C. Everett Koop, chief surgeon of Children's Hospital of Philadelphia and later surgeon general of the United States, condemns abortion even in case of severe birth defects.
1976 - The U.S. Supreme Court rules that a woman does not have to get her husband's consent to have an abortion.
National Republican Party adds an anti-abortion rights plank to its platform.
1978 - Dr. Bernard Nathanson, a founder of the National Abortion Rights Action League (NARAL) who says he has overseen 70,000 or more abortions, changes his mind. He now believes abortion is wrong.
1980 - U.S. Supreme Court upholds the Hyde Amendment, named for U.S. Rep. Henry Hyde, R.-Ill. It bans the use of Medicaid funds to pay for most abortions sought by women on welfare.
1980 - National abortion rate peaks: 25 abortions per 1,000 women of child bearing age.
1981 - Amniocentesis, a test in fifth month of pregnancy, is in wide use. It can identify hundreds of congenital defects in fetus, allowing parents to decide whether to abort. Amniocentesis also allows parents to know the gender of the fetus, transforming the experience of many pregnancies
Human Life Amendment to the Constitution proposed in Congress. Would declare all conceptions to be legal ``persons'' under the law and outlaw abortion for any reason. 1982 - Pioneering surgery on fetus at Jefferson Hospital corrects brain defect before birth
1983 - U.S. Supreme Court upholds state laws requiring pregnant minors to obtain parental consent before having abortions.
1984 - Food and Drug Administration determines that ultrasound imaging, which shows fetus in the womb and is already in wide use, can be beneficial for pregnant women and their fetuses.
1985 - ``The Silent Scream,'' a movie produced by Dr. Bernard Nathanson, shows ultrasound image of an abortion that purports to show a fetus screaming. ``Pro Life'' groups compare it to ``Uncle Tom's Cabin'' in its power to change minds.
1986 - Home pregnancy tests now sophisticated enough for a woman to determine if she's pregnant within one day of missed menstrual period.
A prenatal test called CVS - short for chorio villus sampling - allows pregnant woman to know at 10 weeks about hundreds of fetal abnormalities.
1988 - Reagan administration bans research on fetal tissue from abortions
New technology means some fetuses born in 23d week of pregnancy can be ``viable.''
RU-486, a pill that induces abortion in the first five weeks of pregnancy, introduced in France. It is banned in the United States.
1989 - In Webster decision, three justices urge reconsideration or overturning of Roe v. Wade and invite states to test restrictions on abortion. Abortion an issue in several political campaigns.
1989 - Pennsylvania Abortion Control Act makes it a felony for an abortion to be performed at 24 weeks of pregnancy or later unless the abortion is necessary to prevent the woman's death or to prevent ``substantial and irreversible impairment of a major bodily function'' of the woman.
1990 - CDC counts peak number of abortions in a year: 1,429,577
1990 - Norplant, a five-year implantable contraceptive, approved for use in the United States. It is the first new birth control method since the 1960s.
1991 - In Rust v. Sullivan, the U.S. Supreme Court upholds the ``gag rule,'' a Reagan-Bush administration policy that prohibits family planning clinics from providing clients with information, referrals or counseling on abortion.
Operation Rescue, a militant anti-abortion rights group, blockades abortion clinics in Wichita, Kan., for 42 days.
1992 - Facing mounting support for fetal tissue research that could provide treatments for Parkinson's Disease, diabetes and other illnesses, President Bush authorizes a ``fetal tissue bank'' to collect tissue from pregnancies not terminated by abortion
1992 - Federal gag rule goes into effect. Some clinics now reject federal funding rather than comply, but many clinics continue the counseling with money from other sources.
1992 - Depo Provera, an injectable contraceptive that lasts for three months, is approved for use in the United States.
1992 - In Casey decision, the U. S. Supreme Court adopts a new standard for government restrictions to abortion: the ``undue burden'' standard. Court upholds all but one provision of Pennsylvania Abortion Control Act, which requires a 24-hour waiting period as well as counseling on abortion alternatives.
1993 - President Clinton lifts the ``gag rule'' and ban on fetal tissue research in one of his first executive orders. He also orders a review of the ban on importing the French abortion pill RU-486.
1993 - New Jersey begins denying additional welfare benefits to women who have more children; both pro- and anti-abortion-rights activists oppose so-called ``family cap'' provisions
Operation Rescue targets Philadelphia. Mayor Rendell warns that clinics will be kept open.
Dr. David Gunn shot and killed at his Pensacola, Fla., abortion clinic by anti-abortion activist. Dr. George Tiller, an abortion physician in Wichita, Kan., shot and wounded by anti-abortion activist Rachelle Shannon.
1994 - In first year since Pennsylvania Abortion Control Act, abortions down 12.3 percent to 39,628.
Dr. John Britton and a bodyguard murdered outside Pensacola, Fla., abortion clinic
Two killed, three wounded in attacks on abortion clinics in Boston and Virginia by John C. Salvi 3d.
Under pressure from Clinton administration, Roussel Uclaf, manufacturer of RU-486, donates U.S. marketing rights of the abortion pill to the nonprofit Population Council.
1995 - Norma McCorvey, the woman who was the pseudonymous ``Jane Roe'' in the 1973 Supreme Court decision Roe v. Wade, announces she now believes abortion to be ``murderously wrong.''
1995 - National abortion rate is 20 abortions per 1,000 women of child-bearing age, down for the fourth straight year. So is total number of abortions: 1,210,883. Latest year for which data are available.
1996 - According to Alan Guttmacher Institute, 84 percent of counties in United States have no abortion provider.
1996 - John C. Salvi 3d, convicted killer of two in 1994 abortion-clinic slayings, apparently commits suicide in prison.
1996 - President Clinton vetoes a ban on a late-term abortion procedure called intact dilation and extraction, but known by opponents as ``partial birth abortion.'
1997 - At least 19 states have adopted bans of late-term abortion procedure. New Jersey assembly overrides Gov. Christine Todd Whitman's veto of state ban on the procedure.
Planned Parenthood announces new abortion technology that allows abortions in first weeks of pregnancy. Family Planning clinics offer ``emergency contraception:'' large doses of birth control pill that will prevent fertilized egg from implanting. Availability of RU-486 delayed again.
1998 - Only 10 of 67 Pennsylvania counties provide abortion services.
New York Times poll says trend in U.S. public opinion turning toward more restrictions on abortion