Such technologies weren't yet seen as a tool that would enhance reproductive choices, but as a possible threat that might be wielded by the state. While Orwell and others may have worried about the social implications of reproductive technologies for humans, animal researchers were celebrating the genetic improvement of their herds as reflected in better milk production. It might have been unnatural, but it wasn't unholy.
So farm researchers became the leading edge of biological research into reproduction. And one thing they'd discovered was simple and amazing: sperm are rugged little biological machines that will always, no matter where and no matter what, look for an egg to fertilize.
By the early s, British scientists had successfully frozen sperm and inseminated a cow, leading to the birth of a little calf they named Frosty. And it was about this time that a graduate student named Jerome Sherman began tinkering with freezing his own sperm, "testing freezing protocols in search of a technique that would maximize the percentage of viable sperm," according to Northeastern law professor and historian of science Kara Swanson's fascinating paper, The Birth of the Sperm Bank , from which this account is largely drawn.
There were three main variables that Sherman optimized by building on existing work in animals: how slowly to cool down or heat up the sperm, how much semen to use, and what kinds of additives to mix into the solution. It's not hard to test for viability, after all.
After thawing out the sperm, Sherman could simply look at them under a microscope and count how many were moving well. To this day, visual inspection remains the dominant way of evaluating sperm quality. Sherman had been more focused on freezing kidney tissue as part of his academic work, but after meeting Raymond Bunge, a urologist out to make a name for himself, his sperm-freezing hobby became his actual scholarly job. Their first paper together describes a technique that seemed to keep the sperm swimming.
Add some glycerol—a sugary chemical sometimes used in low-fat cookies —then slowly bring down the temperature. They published their findings in the Proceedings of the Society for Experimental Biology and Medicine. By the time the paper came out, three women had been inseminated with the previously frozen sperm. Bunge was on the staff at Iowa's fertility clinic, and so within months of Sherman's experiments beginning, the duo had real patients on whom they could test the new procedure.
By July, three pregnancies were in progress: they were to be the first children conceived with sperm that had been frozen and thawed. The two scientists had quickly translated animal breeding science into human reproductive medicine. They tried to publish the results in the journal Science , the most prestigious American publication, but we're turned down until "the products of the conception have been observed. In other words, they weren't sure how the babies would turn out.
They X-rayed the fetal skeletons—a common procedure at the time—and everything seemed okay. So they sent their paper to Nature in Britain, where it was accepted. The article appeared in October That announcement eventually caught the attention of the New York Times , among others. Abstract O, Monday 24 June Long-term cryostorage of semen in a human sperm bank does not affect clinical outcomes.
Background notes 1. Donor sperm must usually be quarantined for up to six months and screened for infections before it can be used. The length of quarantine is dependent upon the type of screening tests carried out, which vary from country to country.
Live births from frozen human semen stored for 40 years. J Assist Reprod Genet ; Live birth with sperm cryopreserved for 21 years prior to cancer treatment: Case report. The primary benefits of freezing sperm are to allow a man to preserve his fertility by using his sperm at a later date or to give an infertile couple, an infertile individual, or a lesbian couple a chance to conceive. There are no risks or side effects to collecting semen samples naturally through masturbation.
If surgical extraction is required, there are small risks, as with any surgery, such as bleeding or discomfort. Sperm freezing has been successfully used since to help individuals conceive healthy babies. The process is safe, standardized, and continues to improve as technology advances. The primary concern with sperm freezing is that not all sperm survive the freezing and thawing process.
However, as most semen ejaculations contain an appropriate number of sperm, the chance of having enough healthy sperm for fertility treatments is very high.
The capability of the surviving sperm cells to fertilize an embryo is not jeopardized during the freezing or thawing process. Cryopreservation is considered to have no time limit, and stored sperm as old as 20 years have been used to create healthy babies. In The News Media Relations.
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