It was the spring of the year and of my first pregnancy. My silhouette was just beginning to round out to the point where planting was awkward but not unmanageable. I settled my knees into the soil and sowed a patch of violas. As I buried the seeds in the ground and patted the dirt over their hiding spots, I thought of my own Seedling, nestled within me for his nine-month germination. I pondered the thread of continuity running through creation: new life begins in darkness, enveloped by mystery.

For King David, the depths of the womb were known only to God:

My frame was not hidden from Thee,
When I was made in secret,
And skillfully wrought in the depths of the earth.
—Psalm 139:15

In our day, however, human reproduction no longer seems so mysterious. Science has revealed exactly what goes on inside the womb, from the meeting of sperm and egg onward. Two new books from Harvard University Press shine an academic light into the secret depths of creation.

On Fertile Ground: A Natural History of Human Reproduction is the work of Harvard anthropologist Peter Ellison. In clean, elegant prose, Ellison has crafted a synthesis of current knowledge in a range of disciplines. As a reader with little background in science beyond high school biology, I found it tough going at times, but those with previous knowledge of anatomy and reproductive physiology will have less difficulty understanding Ellison's terminology, and his exposition offers a superb overview.

A book more likely to end up in a "Reproductive Biology for English Majors" class is Making Babies: The Science of Pregnancy, by David Bainbridge. The playful title suggests the book's flavor. Bainbridge, a professor at London's Royal Veterinary College, covers his subject like an academic reporting for the National Enquirer. His eye for the sensational and amusing aspects of pregnancy, combined with his understated sense of humor, results in a more digestible—but still solidly scientific—read.

The books complement each other well. On Fertile Ground covers the whole range of human reproduction, from conception to menopause; Making Babies focuses specifically on pregnancy, telling the story of a single baby (and his mother) from conception through breastfeeding. As a nonscientist, I am not qualified to judge much of what Ellison and Bainbridge have to say. But both authors aim to reach a wide audience beyond their specialized fields, and I'm grateful for their efforts to draw the rest of us into the conversation. Science isn't done in a vacuum—it has a great effect on our lives, on our families and communities. For me as a wife and mother, the science of reproduction is not an object of abstract curiosity but rather the stuff of my daily life. I read both books with my newborn son Gideon in my arms. It was especially fascinating to learn the details of the journey we had just come through together. But I was also prompted to wonder if this knowledge will increase our awe and respect for human life.

Had he studied the human reproductive system, I believe King David would have found many wonders to sing about. I was enthralled by Bainbridge's account of conception in Making Babies, which provided me with an interesting "fact for the day" to share with my family: how a female egg is protected from penetration by multiple sperm ("polyspermy"), a threat to new life at its earliest stage. The moment a sperm enters an egg, an electrical current spreads from the sperm's entry point across the egg's surface, creating a force field against further sperm. In case that's not enough, there's also a backup system: the voltage change from the initial protection measure causes calcium atoms to leak into the egg, triggering the release of hundreds of little chemical packets. These packets fill the space between the egg and its protective shell, the zona pellucida—wonderfully described by Bainbridge as "a clear glassy sphere with a structure rather like a crystal, and clearly unlike anything else in the human body." The zona's very molecular structure is altered by the chemicals, rendering it impenetrable to sperm.

All this I excitedly recounted to my mother, my 14-year-old brother, and my 16-year-old sister one morning at the local coffee shop. My siblings were not impressed. When we got back to the car, they chastised me for "shouting" the words sperm and egg in a public place.

I'm not the only one who takes obvious delight in the miraculous workings of sperm and eggs. "Each of us is a little miracle," Bainbridge proclaims, "the product of a million-to-one coincidental meeting of one sperm and one egg that burgeons into a living, breathing person. Although everyday life may make us forget it, this chance encounter is at the root of each one of us."

There is a never-ending stream of things to wonder at in the making of a human life. "As soon as its maternal and paternal chromosomes are joined," Ellison writes, "the new organism is genetically distinct from its mother and vulnerable to attack by her immune system." An intricate dance between mother and child begins, as the newly fertilized egg gives off chemical signals letting its mother's body that she is pregnant. Does our knowledge of these marvelous processes really prove, as Bainbridge believes, that we are the products of chance encounters? Or does it confirm King David's words that we are "fearfully and wonderfully made"?

These would seem to be theological questions, which the scientific evidence alone can't answer. During the recent pbs series Evolution, it was argued that evolutionary science is compatible with religion because evolution answers the "hows" of life while religion addresses the "whys." Perhaps many scientists see their roles as limited to exploring the "hows," but Ellison and Bainbridge would certainly object. They believe that science has answered (or eventually will answer) all the "whys" of human reproduction.

As Bainbridge asserts, "Until the twentieth century … we often [made] sex, fertility, male and female into primal forces in our myths of how the universe conducts its affairs. In the last century, however, science has told us the answers to all these questions. We now know the reasons why there are men and women, why they have to unite to make a baby, which parent contributes more to the baby, and why it is women who get pregnant."

"Over the centuries," he continues, "it has gradually become clear how, within the first seven hectic weeks of pregnancy, the embryo changes from a single cell into a recognizable baby with eyes, ears, fingers and toes. During this scientific quest we have found out not only how we are made, but also why we are made this way."

Why do we have sex? The "main reason," Bainbridge replies, is that sex "stirs the genetic pot and constantly mixes human genes into new combinations that make new people." Christian revelation would respond in a completely different manner. In his incomprehensible love, God chose to create the world, and he created man in his own image. Sex allows wives and husbands to share God's love by becoming "one flesh"—and even to create new life that bears God's image, as well as our own distinct genetic characteristics. Yes, sex enhances the gene pool, but this is only an observation—not an explanation. If you think science has solved the mystery of sex, imagine whispering in your spouse's ear, "Honey, let's mix some genes."

Ellison, too, details specific evolutionary theories that answer the "whys" of our bodies' reproductive design. Like King David, Ellison believes that our bodies are magnificently designed; or at least appear to be. Here are some examples of Ellison's statements on design (with emphasis added):

Human reproductive physiology appears designed to run the narrow course between competing risks.

Our locomotory apparatus from the pelvis down shows considerable evidence of efficient design for bipedal locomotion.

But even with this elegantly engineered architecture, maintaining an adequate circulatory flow is a difficult feat.

Designing female reproductive physiology to be sensitive to the relative metabolic load of lactation results in an elegant balance among these three.

In each of these examples, the "designer" turns out to be natural selection, not God. Whenever Ellison invokes natural selection, it takes on the attributes of God directing creation. For example, "Natural selection has adapted placental morphology to provide for an enhanced rate of nutrient transfer." And, "It should come as no surprise, then, that natural selection has provided physiological mechanisms to reduce the likelihood of overlapping gestation and lactation."

I found that in all of Ellison's sentences attributing our design to natural selection, when the term was replaced with "God" his logic was made complete. He looks at the painting and seems to credit the paintbrush for the magnificence of the work. This is not to imply that natural selection is incompatible with God—but often in these books, natural selection itself becomes a deity.

While I'm fascinated by the scientific discoveries about reproduction detailed in these books, I am also wary of how that knowledge was acquired and how it will be used. Bainbridge offers this nonchalant account of his work in a research group: "I was trying to develop methods of in vitro fertilisation (ivf) for deer … The sperm and eggs were … mixed in a plastic dish and I usually had a few seconds to watch them before returning them to their warm incubator … I watched the sperm swarm into view and crowd towards the waiting eggs."

Of course, scientists do the same with human eggs and sperm. They attempt to peer into the darkness, to see the hands of God at work. Not seeing God's hands, but only sperm and eggs colliding, they fancy it all chance. Scientists routinely "create" and destroy embryos, and much of what we know about human reproduction was probably discovered in these experiments. Yes, it's interesting to know how a fertilized egg protects itself against polyspermy, or exactly how a tiny embryo develops. But at what cost?

While both authors use terms like "miracle" and "design" to describe life, neither believes that life is miraculous or designed in the commonly understood sense of those words. If the world is the product of natural selection and chance, there is no room for interaction with the supernatural. Bainbridge makes this clear in his chapter on why we have sex: "When the early Christians wished to infuse Jesus' otherwise mundane earthly life with a hint of divinity," he writes, "they claimed that he was produced by virgin birth. Virgin birth was so obviously impossible in the normal course of events that this plot device was enough to set the Messiah apart from all those run-of-the-mill prophets."

If there is no God, there can be no man created in his image. And so another unsettling aspect of these books, which both Ellison and Bainbridge take for granted, is the treatment of man as just another animal. "How did an animal something like a chimpanzee give rise to a creature so smart and talented that it often has trouble thinking of itself as an animal at all?" Ellison asks. When chimpanzees write books, maybe we'll find out.

I find greater wisdom in the words of my friend Edona, a seven-year-old refugee from Kosovo. When she visited my parents' house, Edona declared that she loved their dog "more than anything!" I reminded her that earlier in the day she had said the same thing about my baby. She retracted her statement and put Gideon back in his rightful place. I asked why she liked Gideon more. "The puppy is good," she answered, "but the baby is real."

Though it seems a strange way to put it, we are more "real" than other animals. To say so is not to devalue the other creatures with whom we share the Earth. They too are given life by God. But only human beings are made in the image of God and will live eternally. You don't have to be a Christian to sense our infinite value. Very few people act like we are mere animals, no more special than any other species. If they did, September 11 would stand for nothing more than the loss of a few thousand chimpanzee-like animals. A cruel and deplorable waste of life, yes, a blow to the gene pool, maybe—but hey, it happens all the time.

In the very last sentence of his acknowledgments in On Fertile Ground, in a note to his family, Ellison seems to agree that life is far more mysterious than his attempts to explain it suggest: "If all the work represented here were swept away I would still know, because of [my wife and sons], that love and family are what it's all about." A nice sentiment, but in light of the rest of the book, what is love? A product of natural selection, designed to aid in the survival of the race? For a more satisfactory answer, we must turn to King David, who not only marveled at the design of his body but also sang praises to the Designer.

—Bethany Torode makes her home in rural Wisconsin with her editor and superb critic, Sam, and their boss, Gideon. The Torodes have written a book titled Open Embrace: A Protestant Couple Rethinks Contraception, due this spring from Eerdmans. Their website is www.torodedesign.com.

Copyright © 2002 by the author or Christianity Today/Books & Culture magazine.
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