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When does human life begin?

A 2011 study published in the American Journal of Obstetricians and Gynecology found that half of the gynecologist-obstetricians surveyed believe that life begins when the sperm meets the egg, that is, the moment of conception. “One-half of US obstetrician-gynecologists (57%) believe pregnancy begins at conception. Fewer (28%) believe it begins at implantation, and 16% are not sure,” the results stated.

To explain the differences in view, the study tested the hypothesis that religious views and opposition to abortion may have affected OB-GYN responses, which they found to be the case. “In multivariable analysis, the consideration that religion is the most important thing in one’s life and an objection to abortion were associated independently and inversely with believing that pregnancy begins at implantation.”

The implication would seem to be that some clinicians are dedicated to unscientific beliefs based on religion rather than simply accepting the facts about when life begins. But it’s also possible that some of the respondents’ views came from scientifically based conclusions about what occurs when a sperm fertilizes an egg—namely, a new human life—which may have informed their views about aborting such a life. In identifying an association in views, the AJOG study doesn’t tell us which came first—the belief in life at conception or the opposition to abortion? It’s an important question, because the opposition to abortion is (I would say almost universally) grounded in the opposition to the intentional taking of human life.

The confusion of when life begins

The language we use today to describe when life begins relies heavily on whether a pregnancy is wanted or not. Sometimes it is altogether confusing. For instance, the earliest a pregnancy test can identify that a woman is pregnant is when she is roughly “four weeks pregnant.” But, here, “four weeks pregnant” is, in fact, about two weeks after conception. Why is this?

According to the American Pregnancy Association, “The development of pregnancy is counted from the first day of the woman’s last normal menstrual period (LMP), even though the development of the fetus does not begin until conception, which is about two weeks later. Pregnancy is calculated from this day because each time a woman has a period, her body is preparing for pregnancy.”

When it comes to why the gestational age starts about two weeks before conception, the Cleveland Clinic notes, “Though it may seem strange, the date of the first day of your last period will be an important date when determining your baby’s due date.”

The American College of Obstetricians and Gynecologists (ACOG) puts it this way: “A normal pregnancy lasts about 40 weeks from the first day of your last menstrual period (LMP). Pregnancy is assumed to start 2 weeks after the first day of the LMP. Therefore, an extra 2 weeks is counted at the beginning of your pregnancy when you are not actually pregnant.”

How can you be pregnant when you’re not pregnant?

About two weeks after one’s menstrual period, ovulation occurs, which is when a woman’s egg is released and looking for sperm to fertilize it. While a new life has not formed yet, the potential is there. If sperm is present, the egg can become fertilized, forming a blastocyte with unique DNA—that is, a set of DNA that’s new and different from its mother and father.

Once an egg is fertilized around “week two” of pregnancy (week two after menstruation), things progress quickly. As the Cleveland Clinic details the days that follow,

Within 24 hours after fertilization, the egg begins rapidly dividing into many cells. It remains in the fallopian tube for about three days after conception. Then the fertilized egg (now called a blastocyte) continues to divide as it passes slowly through the fallopian tube to the uterus. Once there, its next job is to attach to the endometrium. This is called implantation.

ACOG describes how pregnancy begins this way:

Fertilization, the union of an egg and a sperm into a single cell, is the first step in a complex series of events that leads to pregnancy. Fertilization takes place in the fallopian tube. Over the next few days, the single cell divides into multiple cells. At the same time, the small cluster of dividing cells moves through the fallopian tube to the lining of the uterus. There it implants and starts to grow. For 8 weeks after implantation, it is called an embryo. From 9 weeks after implantation until birth, it is called a fetus.

The time between when an egg is fertilized (conception) and when it is implanted can range from 6 to 12 days, and according to some, this is the crucial moment in determining when a woman is actually pregnant. But given the short window between fertilization and implantation, why is implantation considered the defining moment for being pregnant? One reason is because of the way certain contraceptive drugs such as Plan B or intrauterine devices (IUDs) work; if the pharmaceutical product stops a fertilized egg from becoming implanted, that raises ethical considerations of whether it ends a life.

“Kind of confusing”

Planned Parenthood has fully grasped the significance of these semantics. “Pregnancy officially starts when a fertilized egg implants in the lining of the uterus,” the organization firmly declares. “It takes up to 2-3 weeks after sex for pregnancy to happen.” This definition of pregnancy, Planned Parenthood recognizes, further separates pregnancy from the gestational age of the baby. As the organization puts it “Gestational age can be kind of confusing, since it measures pregnancy from your last period—about 3-4 weeks BEFORE you’re actually pregnant.” So, according to Planned Parenthood, a woman could be both four-weeks pregnant . . . and not pregnant at all.

A lot is at stake in maintaining this seemingly odd distinction. According to the Guttmacher Institute, Planned Parenthood’s research arm, the “[implantation] definition is critical to distinguishing between a contraceptive that prevents pregnancy and an abortifacient that terminates it. . . . Drugs and devices that act before implantation prevent, rather than terminate, pregnancy.”

So, if pregnancy doesn’t “officially” begin until implantation, then the drugs or devices that Planned Parenthood provides that destroy a fertilized egg before implantation can be described as “preventing pregnancy” rather than terminating it. This labeling can give women the impression that such “contraception” keeps life from forming, when, in fact, it causes the destruction of a fertilized egg with the complete genetic makeup of the baby who would be born nine months later.

From embryo to fetus

While Planned Parenthood and organizations advocating for abortion services gloss over the development of an embryo between fertilization and implantation, there are other highly popular resources on reproductive health that offer the exact opposite. Pregnancy apps for expecting moms show detailed depictions of every stage of embryonic and fetal development.

One app published by BabyCenter, “the world’s number one digital parenting resource, with content that reaches more than 100 million people monthly,” shows detailed illustrations of the baby’s development. “Week two” shows sperm approaching an egg in the moment of conception. Three weeks later, at “week five,” moms are informed that “the heart is already beating” and shown a realistic image of the growing embryo slowly reaching baby-shape; “the neural tube that will become the brain and spinal cord is forming,” it continues.

By week eight gestation (five weeks after conception), the image distinctly resembles a baby, and by week eleven, moms are informed, “You now have a fetus. Your baby is no longer called an embryo. This week is the beginning of the fetal period. All vital organs should be in place, and many have already started to function.”

BabyCenter states its content is “doctor approved and evidence based,” touting an advisory board including dozens of OB-GYNs and other medical professionals. Gone are the days when all we knew of fetal life was from a grainy first-trimester ultrasound. Myriad detailed and clear images of fetal development are just a Google search away for anyone today.

“A desire for uncertainty”

What’s striking is the stark difference in information and language offered about fetal development from outlets catering to women with unwanted pregnancies and those catering to women with wanted pregnancies. Planned Parenthood brushes over early development while BabyCenter details every step of fetal development in minute detail. It makes sense since each is marketing very different services. (Another area in which it is becoming more common to speak frankly about the “life” of an unborn baby is in the realm of miscarriage. Pregnancy loss is gaining increased recognition and acknowledgment as the loss of a person, no matter how early the development.)

Also striking is that through the language they use, contraceptive pharmaceutical companies and groups like Planned Parenthood implicitly acknowledge the ambivalence and discomfort of many women toward the services they provide. For example, Planned Parenthood and contraceptive pharmaceutical companies have long dismissed abortifacient qualities in IUDs and emergency contraception because any destruction of embryos takes place before implantation, and therefore, before the “official” start of pregnancy.

Now they are attempting to provide early abortion services to women who think they “might” be pregnant—but don’t want to know for sure if they are. Abortion advocates have developed a new strategy to provide abortions to women while not telling them whether an abortion has taken place. By branding abortion pills as “missed period pills,” some reproductive health-care providers are hoping to reduce unwanted pregnancies while minimizing women’s mixed feelings on whether it ends a life. The drugs mifepristone and misoprostol can be administered as early as 28 days after a woman’s last period and work in tandem to block progesterone needed to sustain pregnancy and induce contractions to expel the uterus’s contents. The idea is that, if a patient expressed mixed feelings about abortion, a healthcare provider could encourage her to take an abortion pill without knowing if she was pregnant or not.

Covering a study that showed some patients might prefer this uncertainty, the New York Times reports, “One participant said that such a service would be ‘a psychological cushion’ for those women ‘who may be unsure of their own feelings on abortion.’ Another said that she thought it would result ‘in less moral conflict,’ and a third that she would feel ‘less guilty of my choice.’”

This reflects a turn from the abortion-rights movement’s campaign to normalize abortion by encouraging women to “shout your abortion,” the New York Times report notes—perhaps because few want to recall and memorialize that day. Hiding it altogether, even from oneself, makes it more palatable.

“We can do a pregnancy test, we can do an ultrasound, or we can do neither,”  Melissa Grant, chief operations officer of the abortion network Carafem, told the New York Times. “The client decides how much or how little she knows.”

The approach raises ethical concerns that abortion providers would be profiting from sales based on women’s fears of pregnancy and limited health knowledge. Further, for a contingent of women, it would mean administering hormone-disrupting chemicals that come with side effects and risks, even for patients who may not be pregnant. Still, providers view it as offering comfort for women who have a “desire for uncertainty.”

Some abortion advocates are now embracing the uncertainty, to the point of ignoring scientific definitions of when pregnancy begins. “Abortion laws are premised on this idea that there’s an absolute categorical difference between terminating a pregnancy and preventing one,” the New York Times quotes a professor of health law and policy. “But the truth is that this line was never very clear because pregnancy isn’t this definitive moment.”

Another abortion advocate tells the Times: “This concept we have of pregnancy as a yes-no event is really very modern.”

It is modern, in that science has advanced our knowledge of biology to certainties of human development that were obscured in previous times. And it’s noteworthy that abortion advocates are now regressing toward perspectives that could appear as a willful return toward the Dark Ages.

Moving guideposts

In its policy on abortion, the American College of Obstetricians and Gynecologists states that it affirms “the legal right of a woman to obtain an abortion prior to fetal viability.”

On its website, the college states that “ACOG is opposed to abortion of the healthy fetus that has attained viability in a healthy woman. Viability is the capacity of the fetus for sustained survival outside the woman’s uterus. Whether or not this capacity exists is a medical determination, may vary with each pregnancy and is a matter for the judgment of the responsible health care provider.”

Fetal viability is not a static guidepost but one that moves earlier and earlier in pregnancy as technology advances. This year, a baby born at 23 weeks weighing 1.1 pounds in Turkey was healthily discharged from the hospital after five months on a NICU incubator. Medicine and technology are increasing life-sustaining options for preterm babies who might not have survived decades ago. Still, in some places, like New York state, abortion is legal up until birth.

While ACOG describes abortion as a medical decision like any other, it is clear it isn’t like any other. Abortion is not by and large a decision made for medical reasons to sustain the health of the mother or child, but for reasons relating to whether the mother wants the pregnancy. If her pregnancy was progressing well and she could carry the child healthily to term, for instance, ACOG says she still has the option of elective abortion before fetal viability. 

In no other area of health care is independent viability a determining factor in whether a person is deserving of continued life-sustaining care. A person on life support is not viewed as a nonperson in the United States, for instance. Their relatives and caretakers can’t elect to terminate them for personal reasons; instead, the health and hopes of the person needing life support are major factors in the medical decision.

While many in the world of reproductive medicine are opting toward grayer areas and less clarity about the science of when life begins in an effort to offer women greater freedom, I prefer a view of women’s empowerment based on providing women more knowledge, not less and providing them greater care, not less, so we are empowered to take the most humane options available. When defining when life begins—and, consequently, what lives deserve protection—I prefer to be more inclusive, not less. In the legal realm, abortion is widely available, and protections depend on where you live; in the political arena, debates will likely continue as they have for decades. But in the world of science, those who believe that life begins at conception appear to have more medically sound backing for their views than past surveys have granted.