New technique lets parents pick baby's gender
The pioneering work of the Genetics & IVF Institute in Fairfax, Va., was discussed yesterday at the annual meeting of the American Society for Reproductive Medicine, which gathered more than 3,000 researchers, clinicians and others in Seattle for the latest news in fertility research.
Most presentations at the conference involved babies — how to have them, how to make sure they turn out healthy, and, in the case of the Virginia institute, how to make sure they are the desired gender.
Dr. Keith Blauer, the institute's medical director, said the technique was 91 percent successful for couples seeking girls, and 73 percent for those trying for boys.
The success rate is much higher than with other, earlier techniques. Most couples who come to the institute want to pick a gender for "family balancing" reasons, but about 15 percent were trying to avoid gender-linked genetic diseases. About 500 genetic diseases, such as hemophilia and Duchenne muscular dystrophy, are linked to the male gender.
The institute's work, which began in 1995, is now part of an FDA-regulated clinical trial looking at the safety and effectiveness of the technique, said Blauer. To adequately answer those questions, the institute needs to produce about 750 children.
The technology used by the institute, originally developed by a U.S. Department of Agriculture scientist, is called "MicroSort," and it works like this: First, sperm, which determines the sex of the child, is collected. Then, the sample is washed to remove debris and inactive sperm. A fluorescent dye is added, which is absorbed by the sperm and attaches temporarily to the DNA, or genetic material, inside the sperm. "Girl sperm," which carry the X chromosome, contain more DNA than "boy sperm," which carry the Y chromosome.
The dyed sperm is then sent through a "flow cytometer," where a laser beam causes the dyed DNA to glow — the more DNA, the brighter the glow. The "bright" sperm (girls) go one way, and the "dim" sperm (boys) go the other.
Concerns have been raised that the dye, or the laser beam, could damage genetic material.
But Dr. Susan Black, a geneticist and infertility specialist with the institute, said defects so far have occurred in the same percentage they would expect in children produced without such procedures. The oldest child produced through such sorting is about 6½, she said.
Black believes the technique is not only helping couples avoid having children with male-gender-linked diseases, but helping them have fewer children than they otherwise might in the quest for a child of the desired gender.
Although about 50 percent of the couples are after girls when they first come to the institute, Blauer said that percentage rises to about 80 percent in those who undertake the procedure. In part, that's because couples with genetic-disease concerns are trying to have girls.
For the rest, Blauer said, women are the primary decision-makers, and they appear to favor girls.
He suspects the 80-20 percent split might even out to 50-50 if the technology were equally good at picking boy-producing sperm.
Each sperm sort costs $2,300. And that doesn't include travel or the cost of the procedure in which sperm meets egg. The simplest and cheapest method of insemination (intrauterine insemination) is also least reliable, and because it's done with fresh sperm, couples must travel to Virginia to have it done.
Frozen sperm can be transported, but the couple will have to use in-vitro fertilization, which involves mixing sperm and egg in a lab dish, then implanting the egg, which can cost up to $15,000.
The institute will sort free of charge for couples who are genetic-disease carriers, Blauer said. But it won't sort for couples who want to pick the gender of their first child — a more controversial use of the technology. And because institute researchers want to hold down the percentage of defects, women over age 39 aren't accepted. The average would-be mother's age, said Blauer, is 36.
A small number of couples terminate their pregnancies when they learn the technology did not result in the desired gender.
Still, sperm sorting hasn't raised the same ethical considerations as pre-implantation screening of embryos, which typically results in destruction of some embryos.
The American Society for Reproductive Medicine's ethics committee last year endorsed pre-fertilization methods of sex selection, such as sperm sorting, for family-balancing reasons, said Dr. Michael Soules, a University of Washington fertility specialist and the past president of the society.
The committee discouraged couples from pre-implantation embryo screening solely to choose the gender of offspring, saying embryos, while not persons in their own right, deserve "special respect" because they have the potential to implant and bring forth a new person.
So far, the only clinic doing the MicroSort is the Genetics & IVF Institute. But many clinics around the country, including Overlake Reproductive Health in Bellevue, have cooperating agreements with GIVF. Yesterday, Blauer and his colleagues announced that they'll open another sperm-sorting laboratory in southern California in January, an affiliation with the Huntington Reproductive Center in Pasadena.
In other news at the conference, researchers said yesterday that health-care professionals are giving women bad information about the age their fertility begins declining.
Obstetrician-gynecologists and nurses, on average, pegged 37 as the age when fertility declines. About 39 percent said they thought fertility was maintained until age 40.
In fact, according to a study published earlier this year, female fertility begins to slide at age 27, and for men, after age 35.
Also announced yesterday were new findings on female libido. A University of Pennsylvania study found that decreased sex drive in older women isn't correlated with low levels of testosterone, but with fluctuations in the hormone. Other ways to dampen the sex drive: having kids in the house, or being depressed.
Carol M. Ostrom: 206-464-2249 or costrom@seattletimes.com