Science

Babies In a Bottle

Artificial wombs and the beginning of human life

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"Human beings used to be…" he hesitated; the blood rushed to his cheeks. "Well, they used to be viviparous."
Brave New World
, Aldous Huxley

According to an article in the current issue of The New Republic, some pro-life activists are practically salivating over the prospect of artificial wombs. Why? Because they believe that ectogenesis would be a knockout punch in the abortion debate.

"[I]f we had the technology to be able to placentize or incubate in a placental environment, then I would say that would be an argument in favor of repeal [of Roe v. Wade]," Kentucky obstetrician-gynecologist W. David Hager says in the article. Hager also heads the Reproductive Health Drugs Advisory Committee at the Food and Drug Administration.

Is ectogenesis really a live option? The New Republic suggests that it could be "a reality within five years." As evidence, the article cites work by Yoshinori Kuwabara, an ob-gyn professor at Juntendo University in Japan. Yoshinori reported in 1997 that he was able to sustain goat fetuses in artificial wombs for three weeks before birth. The kids were kept in acrylic containers filled with amniotic fluid and attached to dialysis machines to remove wastes. Many of the goats apparently did not fare well, dying shortly after being decanted.

More recently, Cornell University infertility specialist Dr. Hung-Ching Liu has taken endometrial cells—the cells that line a woman's uterus—and embedded them in a biodegradable scaffold of collagen shaped like a uterus, then dosed them with various hormones and nutrients. Embryos attached themselves to the walls of these artificial wombs much like they do in normal wombs. After the embryos attach, cells in outer layer of the blastocyst begin invading the endometrium's wall, seeking out blood vessels from which to derive nutrients and dispose of wastes. However, Liu's artificial uteruses don't have blood vessels to supply nutrients, so how far embryos attached to them would develop is unknown. Although optimistic, Liu recognizes that the day when a baby could be brought to term in an artificial womb remains distant.

Artificially supplying and managing nutrients, eliminating wastes and orchestrating delicate hormonal balances over the course of a pregnancy are vast problems that will not be easily solved.

However, Liu's research could yield more immediate practical benefits, such as helping develop a method for jumpstarting pregnancies outside of women who are infertile due to damage to their uterine walls. Once started, the artificial womb and attached embryo might be inserted into an infertile woman's uterus to overcome her infertility. But rather than expending all scientific talent and resources developing artificial wombs, I suspect that it will be much easier and cheaper to establish pregnancies with human embryos in other mammals, like cows and horses, than it will be to achieve the same thing using artificial uteruses.

In any case, ectogenesis seems very much like fusion power—always just five to ten years away from becoming a reality.

Setting aside the practicalities, would safe effective ectogenesis really mean, as The New Republic article asserts, that "the legal and philosophical premises underpinning Roe could be completely dismantled"? Not likely.

According to pro-life fundamentalists, a fertilized human egg, no matter if it is located in a womb or petri dish, is already a complete human being deserving the same rights and privileges accorded to, say, a 35-year-old brain surgeon. Obviously the existence of artificial uteruses wouldn't alter that view. So what pro-lifers like Hager hope (and what The New Republic apparently fears) is that safe, effective ectogenesis, by making the process of embryonic development visible, will push Americans who favor abortion rights to change their minds.

But the advance of reproductive technologies like ectogenesis is at least as likely to shift people's thinking in favor of choice, as it is toward a pro-life stance. Efforts like the Visible Embryo Project are bringing the wonder of human development out into the open, and simultaneously making it clear that early-stage human embryos are not persons. There is no denying that the images in the Visible Embryo Project do prompt one to think about where the line should be drawn—three months, one month, 14 days? (The Centers for Disease Control and Prevention estimates that 55 percent of abortions in the United States occur in the first eight weeks of gestation, and 88 percent within the first 12.)

The Supreme Court's 1973 Roe v. Wade decision was just such an exercise in line drawing. As Justice Harry Blackmun wrote in the majority opinion, "We need not resolve the difficult question of when life begins. When those trained in the respective disciplines of medicine, philosophy, and theology are unable to arrive at any consensus, the judiciary, at this point in the development of man's knowledge, is not in a position to speculate as to the answer." As much as our understanding of human embryonic development has advanced, we are no closer to resolving these issues today. Nor should we expect to be; although sometimes probative, better scientific knowledge simply can't tell us what we ought to do.

In Roe the Supreme Court essentially forbade abortion at the point of viability, which the justices suggested began at 28 weeks of gestation. Medical technology now regularly rescues premature babies born after 22 or 23 weeks, and a very few fetuses even survive after only 19. However, as the American Academy of Pediatrics makes clear, parents and their physicians have the moral responsibility for drawing the lines—that is, making the life-and-death decisions about treating these babies. In our pluralistic society, that is where the responsibility rightfully rests. And if this is true for babies born prematurely, it is surely no less true for embryos and fetuses at earlier stages of development.