Letter to the Author of "Origins," A Book About Fetal Development

Slate Magazine (Double X): Lessons From the Womb, from Amanda Schaffer to Annie Murphy Paul:

How Does Anxiety Affect Fetal Development?

Dear Annie:

We must begin with the water-balloon condoms. In the 1950s, researchers balanced these on the bellies of pregnant women and sent sound waves through them, as part of the invention of medical ultrasound. This allowed them to peer into the womb for the first time, as you describe in your elegantly written book Origins. Early glimpses, like "grainy footage beamed back from the first moon landing," begot more sophisticated images, like the clay-colored, sculptural ones you got to see of your own son when he was in utero. I love these details, both for their own sake and as emblems of the scientific desire to eavesdrop on fetal life.

As you write, researchers have increasingly probed how a little "lima bean with a beating heart" interacts with its mama, her womb, and the chemical and sensory "postcards" it receives, care of her, from the outside world. You argue that old-school Western medicine often viewed the fetus as a "perfect parasite," relatively impervious to external influence—yet today, a burgeoning literature lays out the lasting influences of the mother's environment and behavior, including her diet, stress level, mood, and chemical exposures. . . .