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Finally, after a third failure, they tried a different approach: doctors retrieved a fresh batch of eggs, and this time they used assisted zona hatching, in which the egg's membrane, known as the zona pellucida, is chemically weakened so sperm can penetrate more easily. (Another way to do this is to drill a tiny hole in the egg; both methods are less tricky than full-fledged ICSI.) Their son, Eric Richard, was born in October.
Like most couples, the Bielickis and the Burskis didn't need the newest assisted-reproduction therapies. That's just as well: these procedures have not entered the mainstream of clinical practice. Some, including R.B.A.'s egg-freezing technique. may never do so. A second patient in the Atlanta clinic is pregnant thanks to a frozen egg; so, reportedly, are three women in Italy, and births have previously been reported in Australia, Germany and Italy. But the success rate is still very low--only two births in 23 tries in Atlanta, so far--and the technique is expensive. So R.B.A. is not yet offering the procedure to healthy women who simply want to postpone childbearing--though scientists hope that will change within a few years.
The same holds true for many other experimental therapies emerging from the lab. One of the most promising is a technique that keeps embryos growing for a few extra days in a Petri dish. Until recently, clinicians had to put in-vitro embryos into the uterus when they were just one or two days old and relatively fragile. After that, the embryos' metabolism changes, rendering standard growth mixtures useless for nourishing them. That's why clinics insert several at once, which raises the odds of success but often produces triplets, quads and even quints.
Australian embryologist David Gardner and his colleagues at the Colorado Center for Reproductive Medicine in Englewood have come up with a mixture that keeps cells growing in vitro for up to five days, making it much easier to pick out the strongest embryos. So instead of three or four or five embryos, doctors can implant one or two. The technique could be a standard practice by next spring.
Another intriguing method involves harvesting not a woman's eggs but bits of her egg-bearing ovarian tissue. Like egg freezing, this procedure could preserve fertility for women who know they are about to lose their ovaries. It could be used on females who are far too young to produce mature eggs--girls who are undergoing radiation treatments, for example. In theory, the tissue could eventually be placed back in the body and lead to successful pregnancies. (This has been done in sheep but not yet in humans.) Men's sperm-generating testicular tissue could also be removed, and presumably re-implanted--though this too has been done only in animals. Routine human therapy using any of these tissue-preserving methods is probably five or 10 years away.