The Nobel Prizes in science and medicine typically recognize the collaborative nature of modern science by recognizing groups of individuals that contributed towards a significant breakthrough. This year, however, the Physiology or Medicine prize is going to a single individual, Robert Edwards, for his efforts in developingin vitro fertilization (IVF). Although Edwards had many key collaborators over the years, his focus on fertilization started in graduate school and spanned decades before culminating in the birth of the first "test tube baby," Louise Brown, in 1978. There are now approximately 4 million individuals alive due to IVF procedures.
Edwards got his start by studying mouse fertilization, which forced him to adjust to the nocturnal animals' reproductive cycle. Apparently getting weary of trudging into the lab at midnight, he began to experiment with manipulating the mouse's ovulation using hormones, eventually enabling him to perform his work at saner hours. IVF is now a key part of modern genetic work, like the generation of knockout and transgenic mice, so Edwards made a significant contribution by this point; he was nowhere close to finished, though.
Switching to humans, Edwards began working with pieces of ovary that had been removed during surgeries. Over time, he began to figure out the hormones and timing that could induce an immature oocyte (egg) in the ovary to mature into a cell that was prepared for fertilization. Combined with information about how sperm is activated for fertilization, Edwards was able to publish the first description of a successful human fertilization that occurred outside a woman's body. That paper, published in 1969, includes the suggestion that "There may be certain clinical and scientific uses for human eggs fertilized by this procedure."
He wasn't there yet, however, as the fertilized eggs managed only a single cell division before dying. Suspecting that the maturation procedure he'd developed was not a complete solution, Edwards began considering using eggs that had matured in a woman's body. To get those, he began a collaboration with Patrick Steptoe, who was developing laparoscopic techniques for what we'd now consider noninvasive explorations of the human body. (This collaboration apparently continued until Steptoe's death.) Steptoe eventually developed the ability to use laparoscopic hardware to harvest eggs from infertile patients.
With this new source of eggs, Edwards was able to get the IVF embryos to develop to the blastocyst stage, when the first specialization of cells becomes apparent. They were now ready to try implanting the fertilized eggs back in patients. The first few attempts failed, probably because the hormone treatments used at the time interfered with implantation. Edwards was willing to work with a single egg at a time and, by the middle of the decade, had gotten at least one pregnancy to take, although that didn't implant in the uterus and had to be terminated.
In 1977, Edwards and Steptoe started working with a couple named Brown, and had a successful implantation by the end of the year. In 1978, the first "test tube baby," Louise Brown, was born, and Edwards and Steptoe published a short letter to the editor of The Lancet to announce their success.
They needn't have bothered, as the event generated world-wide media attention, and a spirited ethical debate. Edwards had also faced difficulty in getting government funding for his work, and had to rely on private donors to continue it. But, with a prominent success, the two researchers set up a clinic in which they further refined the technique and taught others how to perform it. IVF quickly spread to other countries, and is widely practiced around the world today. Louise Brown is now one of millions of IVF babies.
And the work continues to be refined. Fittingly, a paper was released yesterday by Nature Biotechnology that used time lapse imaging to track the first few cell divisions of IVF embryos. Its authors found that, within two days of fertilization, embryos that will go on to successfully show three specific properties that can be measured noninvasively by an automated microscope system. With the measurement of these properties, they could predict which embryos would make it to the blastocyst stage with over 90 percent accuracy.
Source: ars technica
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