Petri dish + hormones = parenthood?

Childless couples pondering in vitro fertilization (IVF) quickly learn that the laboratory is neither an inexpensive nor a congenial place to conceive a baby. Now, a technique being tried in the United States may turn petri dish parenthood into a more tolerable experience that many more couples can afford.

What the new method won't do, scientists say, is turn a gamble into a predictable success-at least for now. Still, Jeffrey B. Russell and his colleagues at the Reproductive Endocrine and Fertility Center of Delaware in Newark, say the technique, called immature oocyte retrieval, promises to reduce the risks, costs, and discomforts of IVF.

In standard IVF practice today, women receive daily injections of powerful hormones for a month or more. The flood of hormones bullies the ovaries into preparing as many as 2 dozen eggs for fertilization, rather than nature's preferred count of one. In about 10 days, doctors nonsurgically suction mature eggs from the ovaries and fertilize them in a lab dish. Fertilized eggs that successfully develop into 32-cell embryos can then be placed in the nurturing warmth of the womb. The newer procedure, which has been used in mice and cows for a decade and was first tried successfully in humans in Korea in 1992, differs from the current routine primarily in its timing. Rather than hastening maturation of eggs within the ovaries, doctors extract immature eggs from the ovaries and push them to mature outside the body.

Scientists bathe the eggs with tiny doses of powerful hormones, a process that causes the eggs to mature. This spares women the daily hormone injections that contribute $3,000 to the IVF bill-and turn every day into a queasy roller-coaster of mood swings, headaches, nausea, and bloating. Worse, doctors say, the injections may confer a slight risk of ovarian cancer.

"What you're looking at is a revolutionary technique in the human reproductive field," Russell says. "We have the capability to stop giving patients most drugs, to eliminate the long-term risk of ovarian cancer, and to decrease the time involved in doing an IVF cycle by 75 percent, with a 40 percent reduction in cost."

The scientist who pioneered the technique in mice in 1984 concurs. "In time, the technique will improve to where it represents a distinct advantage over earlier techniques in success, safety, and cost," asserts John Eppig of Jackson Laboratory in Bar Harbor, Maine.

If the new method even partly meets such lofty expectations, it promises to attract many more childless couples. Demand for the current procedure in the United States has spawned a $2-billion-a-year industry, despite medical bills approaching $9,000 per attempt and success rates of just 18 percent.

Russell, who described the research on April 30 at a meeting of the American College of Obstetricians and Gynecologists in Denver, produced embryos for six of the first eight patients on whom he tried the new technique. These women had tried standard IVF unsuccessfully a total of 18 times. One woman became pregnant and gave birth to a baby girl.

Although this single birth amounts to a success rate of just 5 percent, Eppig says Russell's record is likely to improve, given time and systematic refinement of his technique.

"As with anything that's revolutionary," Russell acknowledges, "we have to go through a steep learning curve to bring this to where it needs to be."

In mice, Eppig says, about 45 percent of eggs matured outside the body produce healthy offspring. "We have produced hundreds and hundreds of mice this way," he says. "We have yet to see an abnormality."