Sharla Miller always wanted a baby girl, but the odds seemed stacked against her. Her husband, Shane, is one of three brothers, and Sharla and her five siblings (four girls, two boys) have produced twice as many males as females. After the Millers' first son, Anthony, was born in 1991, along came Ashton, now 8, and Alec, 4. Each one was a gift, says Sharla, but the desire for a girl never waned. "I'm best friends with my mother," she says. "I couldn't get it out of my mind that I want-ed a daughter." Two years ago Sharla, who had her fallopian tubes tied after Alec's birth, began looking into adopting a baby girl. In the course of her Internet research, she stumbled upon a Web site for the Fertility Institutes in Los Angeles, headed by Dr. Jeffrey Steinberg, where she learned about an in vitro fertilization technique called preimplantation genetic diagnosis. By creating embryos outside the womb, then testing them for gender, PGD could guarantee--with almost 100 percent certainty--the sex of her baby. Price tag: $18,480, plus travel from her home in Gillette, Wyoming. Last November Sharla's eggs and Shane's sperm were mixed in a lab dish, producing 14 healthy embryos, seven male and seven female. Steinberg transferred three of the females into Sharla's uterus, where two implanted successfully. If all goes well, the run of Miller boys will end in July with the arrival of twin baby girls. "I have three wonderful boys," says Sharla, "but since there was a chance I could have a daughter, why not?"

The brave new world is definitely here. After 25 years of staggering advances in reproductive medicine--first test-tube babies, then donor eggs and surrogate mothers--technology is changing baby-making in a whole new way. No longer can science simply help couples have babies; it can help them have the kind of babies they want. Choosing gender may obliterate one of the fundamental mysteries of procreation, but for people who have grown accustomed to taking 3-D ultrasounds of fetuses, learning a baby's sex within weeks of conception and scheduling convenient delivery dates, it's simply the next logical step. That gleeful exclamation, "It's a boy!" or "It's a girl!" may soon just be a quaint reminder of how random births used to be.

Gender selection is one of many advanced techniques doctors have developed to assist in conception. As the technologies spread, they've fueled a worldwide boom in assisted-reproduction treatments (ART). Couples from disparate cultures, nationalities and religions all share at least one thing: a powerful drive to have children of their own genetic stripe, which often compels them to go to extraordinary lengths--traveling great distances and spending huge amounts of money on treatments.

Doctors in a handful of countries--including India, South Korea, Israel, Italy and the United States--have begun to cater to this international clientele. "Our technology is only six months behind that of the West," says Dr. Hrishikesh Pai, an infertility specialist at the Lilavati Hospital in Mumbai, India, which reports a steady rise in foreign patients. "The Internet has given us a chance to convey this to the West." Steinberg's clinic, which has an office in Mexico, will soon perform its 100th PGD sex-selection procedure. A third of them were performed for couples who had traveled from Hong Kong, Egypt, Germany and other countries.

Infertility medicine, which makes it possible for mothers in their 60s to give birth, gay and lesbian couples to conceive their own genetic offspring and (perhaps in the not-too-distant future) bereaved parents to clone their lost child, is already prompting a legislative backlash in some countries. Gender selection may only worsen matters by galvanizing opponents of ART. Already, many couples are forced to travel far and wide for access to the latest procedures. In the near future they almost certainly will have fewer places to go.

Despite the moral murkiness of gender selection, demand for the service seems to be taking off. People query their doctors and visit catchy Web sites like and of them offering money-back guarantees. In the past six months Steinberg's site has had 85,000 hits. And PGD isn't the only ticket to selection for a boy or a girl. At the Genetics and IVF Institute in Fairfax, Virginia, a U.S. Food and Drug Administration clinical trial of a sperm-sorting technology called MicroSort is underway. The clinic has recruited hundreds of couples, and more than 400 babies out of 750 needed for the trial have been born. Other couples continue to flock to older, more low-tech and questionable sperm-sorting techniques like the Ericsson method (graphic). PGD, though, is by far the most provocative gender-selection technique. Some clinics offer the procedure as a bonus for couples already going through fertility treatments, but a small number are beginning to provide the option for otherwise healthy couples. Once Steinberg decided to offer PGD gender selection to all comers, he says, "word spread like wildfire."

The ability to create baby Jack or baby Jill opens a high-tech can of worms. While the advances have received kudos from grateful families, they also raise loaded ethical questions. Even fertility specialists are divided over whether choosing a male or female embryo is acceptable. What's next on the slippery slope of modern reproductive medicine? Eye color? Height? Intelligence? Could picking one gender over the other become the 21st century's form of sex discrimination? Or, as in China and India, upset the ratio of males to females? Many European countries already forbid sex selection; should there be similar regulations in the United States? In South Korea?

Some countries are beginning to clamp down even on less-controversial fertility procedures which have been extended to morally questionable lengths. Over the past two decades Italy, perhaps more than any other country, has been known as the "Wild West" of assisted fertility. Several clinics in Rome have created "house conception" labs where couples go, essentially, to copulate, while doctors intervene at crucial moments with swabs, lotions and injections to help nature along. No doctor or clinic, though, tops gynecological maverick Dr. Severino Antinori of Rome. Among his most notable accomplishments: in 1994 he helped a 62-year-old woman become the oldest to give birth. He's been known to harvest eggs from women in the Balkans or Sicily and market them for their genes, which confer blonde hair or olive skin. And he's now trying to be first to clone a human.

The British and Italian medical boards have questioned Antinori's ethics, but he doesn't see what's wrong with helping women conceive. "These women come to me when they have nowhere else to go, and I help where I can," he says. "Every woman has a right to have a child." The Vatican, which calls his work "horrible and grotesque," pressured the Italian Parliament to pass new laws in December outlawing surrogate parenthood and IVF for elderly couples. As the laws take effect over the next few months, they'll put an end to a booming industry that caters to Europeans seeking to circumvent similarly strict laws in their home countries.

That in turn has prompted a minor panic at Italy's 2,500 fertility clinics, which will have to scale back the range of services they offer. Loretta Falcone, a 41-year-old living near Milan, has struggled with various fertility treatments for a few years without success. In December her doctors said that IVF was her last remaining option. But soon the new laws will limit the number of eggs that can be harvested to three for each patient and require doctors to implant all viable embryos. If she can't have the procedure done before the laws take effect in a few weeks, she's considering having the embryos implanted in Kiev.

Italy isn't the only place where infertility is a hot issue. In the United States, the religious right, which opposes abortion and just about any tampering with reproduction, exerts steady pressure for new laws. Two weeks ago President George W. Bush's Council on Bioethics discussed proposals for possible legislation that would ban the buying and selling of human embryos. --While the council's current recommendations don't limit IVF or gender selection, the goals are clear: the government should clamp down before technology goes too far. "Even though people have strong differences of opinion on some issues," says council chair and leading bioethicist Leon Kass, "all of us have a stake in keeping human reproduction human."

Even fertility-related research has lately been on the run. Scientists in the United States, for instance, have chafed under the federal prohibition against using government funds for research on human embryos, including for such nonreproductive purposes as harvesting stem cells or therapeutic cloning. In recent years, a team of U.S. researchers developed a technique for transplanting the nucleus from one fertilized human egg cell to another egg cell--a procedure that could allow an older woman, whose eggs have passed their use-by date, to "borrow" the egg of a younger woman. Unlike with a typical donor egg, though, the older woman would be able to pass along her genetic traits to her offspring. The scientists wanted to pursue the technique in the United States, but because it was too similar to techniques of nuclear transfer used in cloning, they were forced to go elsewhere. Thinking that they'd have better luck in China, where there's little public pressure to curtail human embryonic work, the American scientists persuaded Zhuang Guanglun, a fertility specialist at Sun Yatsen University in Guangzhou, to take up the research. Last October, the team reported that they'd used the technique to help a 30-year-old Chinese woman, who had never been able to carry a pregnancy full term, give birth to triplets.

If the scientists were expecting to be treated as heroes, they were disappointed. When the treatment was announced at a conference in San Antonio, Texas, it was greeted with an outcry heard halfway around the world. One ethically complicating factor was that even though most of the children's DNA came from the two parents, the borrowed egg cell's surrounding cytoplasm also contained some of the donor's DNA. Did that mean the children had three parents? The technique was also, as the researchers had feared, seen as being similar to those used in human cloning. The Chinese government promptly squelched the research. The team that performed the work has disbanded.

Despite its image as a haven for far-out medical research, China has actually been more diligent in its legislation than countries like Italy so far. Two years ago, in the face of proliferating fertility services, Beijing banned surrogacy and payments to egg donors and restricted the number of IVF cycles a clinic can perform. Last fall the authorities moved to ban advertising of infertility treatments and restricted the number of fertilized eggs that can be implanted to two for each woman under 35, and three for each woman over 35. As in India, where it's illegal to use ultrasounds or amniocentesis to determine the sex of babies (for fear that female fetuses will then be aborted), the law is not the problem so much as social attitudes. The gender-selection technology that's most dangerous--one that's skewing sex ratios in Asia's two largest populations--is simple female infanticide.

In a few years there may not be many countries left that perform the latest reproductive techniques. The ones that remain--like Israel, perhaps--may see business boom. Last year the Israeli government tried to cut back on state-supported IVF treatments, to one child per family from two, but backed off in the face of stern opposition. Israel has 30 IVF clinics and produces more scientific papers on fertility per capita than any other country. The Assuta Hospital in Tel Aviv performs almost 4,000 cycles of IVF each year. Because treatments are subsidized by the state and labor costs are rather low, clinics are able to charge overseas patients only about $3,000 a cycle for IVF--a quarter what U.S. clinics charge. In India and South Korea as well, fertility has become a fast-growth export industry. "There's nothing I want more than my own baby," says Helit, a 33-year-old American woman who recently traveled to a Jerusalem hospital for infertility treatment, "and if I have to travel all over the world, I'll do it." No doubt she will not be alone.