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Many of us know someone who would
desperately like to have a child of one gender or the
other. Perhaps a couple has one or more children of
one gender already and would like to have another child
--- but would only consider doing so if the 50/50 odds
could be shifted in favor of the other gender. Or, perhaps
a couple already seeking fertility treatment has one
child, and would prefer that the next child is the other
gender if possible. Yet another couple may want to avoid
passing a gender-linked genetic disease to their child.
If a scientifically proven method of gender selection
existed, most of these individuals would consider using
it.
The
Huntington Reproductive Center, in partnership with
the Genetics and IVF Institute, is currently investigating
the only proven gender selection technology presently
available. This technology is called MicroSort©
and is now available at MicroSort West in southern California.
MicroSort© is now being utilized as part of an
FDA clinical trial for preconception gender selection
process. This research began in the early 1990s.
When
a sperm with a Y chromosome fertilizes an egg, it makes
a boy. When an X chromosome bearing sperm fertilizes,
it makes a girl. Any given sperm sample contains an
even (50/50) amount of X (female) and Y (male) bearing
sperm. MicroSort uses a machine called a flow cytometer
to sort sperm such that the sorted sperm population
is enriched in either X (female) or Y (male) bearing
sperm. Once the sperm has been sorted, it can be used
with assisted reproductive techniques to achieve a pregnancy.
Since it is in a clinical trial, patients must be fully
informed of the potential risks and benefits.
The
separation of male and female sperm is based on the
measurable difference in the quantity of genetic material
(DNA) they contain. The sperm absorbs a dye, which attaches
temporarily to the DNA, or genetic material, inside
the individual sperm. When exposed to laser light, the
dye fluoresces. Since the X chromosome is larger than
the Y, there is more DNA for the dye to attach to and,
consequently, the sperm with the X chromosomes will
fluoresce more brightly than those with Y chromosomes.
The flow cytometer is able to pick up these differences
in brightness and separate the sperm as they move through
the machine time.
Currently, MicroSort sperm sorting technology improves
the chance of a female pregnancy to 89.5 percent after
sorting. For a male, MicroSort has improved the chance
to 73.6 percent.
The
most common method uses the sorted sperm with intrauterine
insemination (IUI). The woman is monitored carefully
to establish the time of ovulation. Some of this monitoring
can occur with her local physician and/or the use of
ovulation predictor kits. Insemination is performed
very close to the time of ovulation. On the day of ovulation
the husband produces a sperm sample, the sperm are sorted
for the desired gender, and the insemination with the
sorted sperm occurs later that same day.
For
patients who need additional assistance achieving pregnancy,
sorted sperm can be used with IVF. Sperm can be sent
frozen, then sorted and returned to a local IVF center,
allowing the couple to have IVF close to home. Please
refer to the MicroSort Web site www.microsort.com for
a full listing of physicians (collaborators) participating
as part of the clinical trial.
MicroSort has accomplished more than 350 pregnancies.
Based on the data so far, the likelihood of having a
normal, healthy baby is not different from that of the
general population.
Currently
couples must be in one of two categories. A couple with
a history of an X-linked disease, where the woman is
a known carrier, may qualify for free treatment with
MicroSort. Examples of such disorders include hemophilia
and Duchenne muscular dystrophy. Other couples can choose
to use MicroSort for family balancing. Family balancing
couples must be married, the wife must be between ages
18 and 39, and they must have at least one child and
be selecting for the less represented gender of children
in their family.
MicroSort
is the only scientifically verifiable method of preconception
gender selection. It is showing positive results after
more than 350 pregnancies. For couples today who are
considering options for having a family, especially
those with chromosome-linked concerns, MicroSort gender
selection is of serious interest. As the science continues
to improve, we expect that MicroSort will become a routine
part of family planning.
Their
is extensive information on gender
selection at the Huntington Web site.
Editor's Note: Daniel A. Potter, MD, FACOG, is a board
certified Reproductive Endocrinology and Infertility
sub specialist with the Huntington Reproductive Center.
Dr. Potter is Medical Director for MicroSort West in
Laguna Hills California.
Caution: This procedure uses an investigational device.
Limited by federal law to investigational use.
Extensive
Infertility Information at the Huntington Site |
