Word: eggs
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Dates: during 1970-1979
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...despite the British team's long experience, the procedure had never resulted in a live birth. To bring it off successfully requires scientific ingenuity, surgical dexterity and, some might say, a lot of plain luck. The doctor must remove the egg at the exact moment in the monthly cycle when it has reached maturity. To ensure the success of that crucial initial step, Steptoe and Edwards follow a standard procedure for treating infertility: they administer fertility hormones, like those that have been responsible for the rash of multiple births in recent years. That encourages the ripening of several eggs...
Equally important, the sperm must be primed for fertilization or, in the technical term, capacitated. This means that the chemical inhibitors preventing the sperm from penetrating the egg must be removed from the surface of the sperm. How this trick is accomplished in the body remains a puzzle; some scientists think that the woman's secretions do the job. But in the lab, experimenters usually are able to prime the sperm simply by gently bathing them in a salt solution. There is also the critical matter of timing: neither eggs nor sperm have unlimited lifetimes, nor does the uterus remain...
Even after fertilization, doctors have no assurance that the egg will divide; again the culture medium must be carefully controlled. Some researchers think that the highest rate of success could be achieved if the content of the solution were continually altered as the cells go through stages of division. Finally, when the egg becomes a blastocyst or shortly before, it is ready for implanting. One way this can be done is by picking up the egg, which is still no bigger than the dot at the end of this sentence, with a tiny hollow tube, or pipette, then inserting...
...egg is placed in a dish containing blood serum and nutrients, to which sperm is added for fertilization...
...Once an egg is fertilized by one of the many spermatozoa, it is then transferred to another dish of blood serum and sustaining nutrients. For the next three to six days, the fertilized egg divides, creating a cluster of cells called a blastocyst...