OPINION | ART HOBSON: On abortion, the political debate is full of misconceptions

Science supports conditional ban at 20 weeks

One of my favorite magazines, Science News, recently published an article titled "Misconceptions cloud abortion debate." It summarizes four misunderstood issues, presented below. Carl Sagan has called science a "candle in the dark." If ever we needed such a candle, it's now in the benighted abortion debate.

First, there is misunderstanding about the "official" date when pregnancy begins. "Day one" is not the day that a sperm cell enters an egg, but rather two weeks earlier than this, on average. This is because "day one" is defined as the first day of the previous menstruation. An ovary releases a single egg on about day 14 of an average 28-day menstrual cycle. This means that, on the day a sperm enters the egg, the woman is already officially about two weeks into pregnancy. This definition of "day one" might seem misleading, but it's the clearest way for the medical profession to date a pregnancy.

Nine states including Arkansas have banned nearly all abortions at any time. Nine others have passed a ban after 6 weeks of pregnancy, but these laws are temporarily on legal hold in five of these states. Such a ban starts just two weeks after the first missed period, which is often a woman's earliest indication of pregnancy, leaving little time to access an abortion.

Second, pregnancy is not simply a matter of a sperm mingling with an egg. The mingling creates a "zygote," usually in one of the two fallopian tubes near the ovaries. But the genetic material needs to combine properly, the zygote needs to travel to the uterus and implant itself in the right spot, and the right combination of hormones is required. Some 50 percent of zygotes fail to complete these steps. State laws that refer simply to "fertilized eggs" can fail to recognize these conditions. For example, the zygote could implant in the wrong place, dooming the fertilized egg and threatening the woman's life.

My own commentary on this is that religious opponents of abortion make a monumental mistake by assigning "spiritual" value to a zygote. A zygote is just a growing ball of cells, certainly not a human being. If a zygote is a human being, then nature is by far the world's most consequential abortionist because 50 percent of zygotes fail.

Third, there are misconceptions about pain. As an example, when you burn your finger, your nervous system sends a signal to your brain's cortex that creates a mental impression, namely "pain." A human fetus does not develop these brain connections until about week 24. Thus a fetus might feel pain by week 24 and certainly not before. In any case, far less than 1 percent of abortions occur after week 24.

Fourth, fetal "viability" is a complex concept. It's supposed to mark the probable survival of the fetus outside the uterus. Today, babies born around 23 weeks into a pregnancy either don't survive or survive with major health problems, so this marks the earliest date of viability. After that date, viability depends on a wide range of health-care issues. Given this complexity and given that less than 1 percent of abortions occur after week 23, the American College of Obstetricians and Gynecologists has removed "viability" as an issue in abortion guidance, concluding that this question needs to be left to medical providers and patients. I conclude that it's a mistake to make viability an issue in the political discussion of abortion.

The article does not discuss the important issue of human brain development. The frequent question "When does life begin?" misses the point. "Life" is not the issue. A blade of grass is alive, but the loss of all this life doesn't disturb us when we mow our lawns. It's human life that should concern us, and human life doesn't begin at fertilization because a zygote is surely not a human being. A fetus does not become a human being until it has developed human attributes. The primary attribute that defines humankind is the human brain, specifically the prefrontal cortex of the human brain that's responsible for uniquely human activities such as abstract thought, language, and complex social interactions. A fetus does not develop a prefrontal cortex until about 20 weeks after conception.

Applying all of this to the abortion debate, there are respectable arguments for banning most abortions after about 20 weeks with exceptions such as saving the life of the mother, but arguments for a ban before that time are dubious, vague and imaginary.