April 26, 2004 -- Jose and Claudia Quintero of Miami, Fla., already had three daughters and wanted a boy to round out their family. Lisa Kreshock of Leonard, Mich., had a strong yearning to add a daughter to her and her husband's family of two boys when she lost her mother to Alzheimer's disease.
Thanks to modern technology, both couples got what they wanted.
Since Dolly, the cloned sheep, was born in 1997 and jolted the world with the controversial possibilities of genetic manipulation, scientists have been talking about moral dilemmas we may face in the future, from human cloning to designer children.
Some say the ability to select the gender of unborn children marks the start of that future. And while the science is here, society seems everything but settled on the implications.
"Children are the issue of our love, not the product of our wills," the members of the President's Council on Bioethics said about gender selection in a recent report.
The United Kingdom has already clamped down on the practice of pre-selecting the gender of embryos for non-medical reasons. Authorities there ruled that only families with a history of gender-linked genetic disorders could tap the technology.
"Great value should be put on the unconditional nature of parental love," Suzi Leather, head of the U.K.'s Human Fertilization & Embryology Authority,said at the time of the November 2003 ruling.
But others argue, what's the harm in choosing?
"When a couple has a strong preference for a baby boy or girl, who is injured by allowing them to choose? Certainly not the child," says Gregory Stock, director of medicine, technology and society at the University of California's School of Public Health in Los Angeles.
Sorting Sperm, Not Embryos
That argument has taken on more force now that some methods have become available which don't require the ethically thorny practice of creating and then discarding embryos of the unwanted gender.
The newer techniques sort sperm, rather than embryos.
Read about methods people may try to select the gender of their child here.
Every cell in the human body contains 46 packages of DNA known as chromosomes, which are divided into 23 pairs. One of these pairs contains sex chromosomes. Women have two X chromosomes while men have one X chromosome and one Y chromosome. The factor that determines a child's sex is which of the man's sperm reaches the female egg.
About half of a man's sperm contain girl-producing X chromosomes, while the other half contain boy-producing Y chromosomes — whichever kind of sperm reaches the egg first wins. But the new methods, some of which remain in question within the medical community, try and control that coin toss.
The Microsort method, available since 1995, is the most widely accepted of these methods. It's based on the fact that X chromosomes are bigger than Y's, so when the sperm cells are doused in a special fluorescent dye, the X chromosomes soak up more of the dye and glow brighter.
The sperm is sorted this way, and then assigned a charge, which tugs them into separate receptacles. The couple selects the boy or girl-producing sperm and uses it for fertilization. The technique (used by the Quintero family) costs about $5,000 per try and is 88 percent effective for couples desiring girls and 73 percent effective for those wanting boys.
Other, slightly older techniques also rely on the weight differences between X and Y chromosomes to sort them, but remain less proven.
In one method, sperm is poured on a viscous layer of fluid. As the sperm swim down, lab workers skim off those which reach the bottom first, assuming that the slightly lighter, quicker Y chromosome-carrying sperm win the race. Another technique spins the sperm, assuming that the lighter Y-carrying sperm will be flung to the outside of the spinner, while the X chromosome-carrying sperm stay more central.
Supporters claim the methods can be up to 85 percent effective in selecting gender, but critics say they don't even alter nature's 50-50 odds.
"Microsort shows some promise, but right now, the only sure way to sex select a baby is to test the embryo before you implant it," said Mark Kan, a specialist in reproductive endocrinology at the Coastal Fertility clinic in Orange County, Calif.
Pre-selecting embryos began as a way for families who have histories of sex-linked genetic diseases to avoid conceiving children with the disease. Using the method just to choose gender is legal, but controversial — the American Society of Reproductive Medicine advises against it. At about $15,000 per attempt, it's also expensive, but appealing to those, such as the Kreshock family, who want a sure result.
One obvious concern is that more families may choose to have boys and this could off-set the balance of the sexes. Cultural preferences for boys have tilted the balance in other countries, particularly China and India.
Research shows that in some parts of China (which enforces a one-child law), there are 120 boys to every 100 girls because of gender selection. In India it is illegal to abort a pregnancy based on gender selection alone, but numbers suggests it happens. The last recorded sex ratio there was 933 females per 1,000 males.
Could the same happen in this country? Stock believes it's unlikely, pointing out that the United States doesn't have the same cultural pressures, such as dowry demands or extensive wife duties that may be factors behind favoritism for boys. And when it comes to Americans and their preferences for boys or girls, the numbers seem mixed.
A 2003 Gallup Poll found that 38 percent of American respondents would prefer a boy if they could have only one child, while twenty-eight percent would choose a girl. Slightly more than a quarter express no preference, while the rest had no opinion. Among parents seeking to adopt a child, agencies report a slight preference for girls — and figures from the U.S. Census Bureau show they're getting girls — U.S. families adopt only 89 boys for every 100 girls.
Jill Swazy, a pharmacist by training and co-founder of an herbal home gender selection kid called GenSelect, argues that many parents have a strong preference for their future child's gender, but rarely voice it.
"Parents don't talk about it much publicly," Swazy says. "But if someone is adamant about having a boy or a girl, one way or another, they're usually going to have that gender, either by screening their embryo or by trying again."
Timing, Diet and Douching
Swazy argues that parents wanting to choose the gender of their child don't have to turn to high tech, but can lean on the herbal methods touted in their GenSelect kit ($199). She claims the program has a 96 percent success rate.
Kits like GenSelect, BabyChoice and Master Plan, among others, mostly rely on anecdotal methods such as timing intercourse, diet and douching, all of which have largely been met by skepticism in the scientific community.
"If you're going to rely on things like diet to choose your baby's sex, you may as well consult a Chinese prediction chart," said Kan. "The truth is, it's still very hard to select your child's gender."
The fact that it remains possible, but expensive to choose a child's gender, may mean that society has a little more time to mull over the consequences of this and other future feats of science. And, experts say, there will be plenty of both.
"This is only the edge of a whole realm," said Stock. "In the future, everyone will have their sensitivities stepped on, from choosing and screening our children's traits and personalities. There are many more controversial issues to come."