Woman: An Intimate Geography Read Online Free PDF

inserted into the vagina, across the cervix, and into the uterus. No big deal: blink and you miss it. Alas, for the women too it's a case of blink and you lose it. In the vast majority of patients, the technique fails. The chance of an older woman giving birth to a baby conceived from her eggs through IVF is maybe 12 to 18 percent. If you heard that these were your odds of surviving cancer, you'd feel very, very depressed.
An older woman may try IVF once or twice, even a third time, but if by then she hasn't conceived with her own harvest of DNA, she probably never will. At that point a doctor may recommend donor eggs, combining the seeds of a younger woman with the sperm of the older woman's husband (or lover or male donor) and then implanting the

     

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resulting embryo in said senior's uterus. Using donor eggs can make a woman of forty act like a twenty-five-year-old, reproductively speaking. Who knows why? But it works, oh girl does it work, so well that suddenly you're no longer in the teens of probability but instead have about a 49 percent chance of giving birth in a single cycle of in vitro maneuvers. That number starts to sound like a real baby bawling. If the wine is young enough, it seems, the bottle and its label be damned.
And so the egg rules the roost. It, not the womb, sets the terms of tomorrow. Carol-Ann Cook takes one of Derochea's eggs and puts it under a high-powered microscope, which transmits the image to a video monitor. "This is a beautiful egg," Bustillo says. "All her eggs are beautiful," Cook adds. They are eggs from a healthy young woman. They have no choice but to shine.
To think of the egg, think of the heavens, and of weather. The body of the egg is the sun; it is as round and as magisterial as the sun. It is the only spherical cell in the body. Other cells may be shaped like cinched-in boxes or drops of ink or doughnuts that don't quite form a hole in the middle, but the egg is a geometer's dream. The form makes sense: a sphere is among the most stable shapes in nature. If you want to protect your most sacred heirlooms your genes bury them in spherical treasure chests. Like pearls, eggs last for decades and they're hard to crush, and when they're solicited for fertilization, they travel jauntily down the fallopian tube.
Carol-Ann Cook points out the details of the egg. Surrounding the great globe that glows silver-white on the screen is a smear of what looks like whipped cream, or the fluffy white clouds found in every child's sketch of a sky. This is in fact called the cumulus, for its resemblance to a cloud. The cumulus is a matting of sticky extracellular material that serves to bind the egg to the next celestial feature, the corona radiata. Like the corona of the sun, the corona of the egg is a luminous halo that extends out a considerable distance from the central orb. It is a crown fit for a queen, its spikes and phalanges emphasizing the unerring sphericity of the egg. The corona radiata is a dense network of interlocking cells called nurse cells, because they nurse and protect the egg, and it may also act as a kind of flight path or platform for sperm, steering the rather bumbling little flagellates toward the outer coat of the egg. That thick, extracellular coat is the famed zona

     

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pellucida the translucent zone the closest thing a mammalian egg has to a shell. The zona pellucida is a thick matrix of sugar and protein that is as cunning as a magnetic field. It invites sperm to explore its contours, but then it repels what doesn't suit it. It decides who is friend and who is alien. The zona pellucida can be considered the mother lode of biodiversity, the place where speciation in nature often begins, for it takes only a minor change in the structure of its sugars to make incompatible what before was connubial. The genes of a chimpanzee, for example, are more than 99 percent identical to ours, and it is possible that if the DNA of a chimpanzee sperm