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The retrieval and subsequent maturation (in culture) of immature human oocytes (eggs) is a technology that (when clinically refined and available) will probably revolutionize IVF.
When in vitro maturation of immature eggs becomes available, we will ultimately be able to obtain hundreds to thousands of immature eggs from (unstimulated) human ovarian tissue biopsies that could subsequently be used for maturation in culture (in vitro). This presumably would replace controlled ovarian hyperstimulation for IVF, which involves the use of (relatively) large amounts of very expensive medications and close monitoring of egg development within the ovaries (ultrasounds and bloodwork) in an attempt to obtain less than 50 (and usually 10-20) mature eggs.
Currently, most attempts at in vitro maturation of eggs have been directed at the completion of maturation of eggs that have already initiated this process (maturation) within the ovaries. Eggs are retrieved from small follicles and maturation is completed in culture. It is important to realize that these eggs have undergone the process (thought to occur over a 3-6 month period of time) that allows them to respond to FSH to mature. Once completion of (partial) egg maturation is better understood, there will most likely be increased attention focused on understanding the processes that allow these human eggs to initiate the maturation process.
With in vitro maturation of eggs, donor egg banks will most likely develop (for use by the donors and possibly for anonymous egg donation). In addition, women anticipating chemotherapy or radiation therapy (for an identified malignancy) may be able to provide ovarian tissue biopsies that could be used in subsequent months (or years) as a source of eggs. Women with premature ovarian failure, menopausal women or women with chronic ovulatory dysfunctions may also be able to benefit from these techniques.
At this time, it appears that there is a tremendous research effort around the world to develop effective techniques for in vitro maturation of immature eggs. There are (a few) reports of successful human pregnancies following these procedures, however, there is currently no generally accepted protocol that is clinically available. As protocols are developed and refined, I hope that a clinically useful (effective) technology will become universally available.
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