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What is Cryopreservation?
Cryopreservation is a method used to "deep freeze" both
embryos and sperm so it can be used at a later date.
The basic technique involves the addition of protective substances
known as cryoproctants that are applied to prepare the specimen
to be frozen.
Liquid nitrogen, which has a temperature of -196 C., is used
to place the specimen in a state called "suspended animation".
Specimens in this state can be stored for long periods of time
and used in the future.
Embryo and Semen
(Sperm) Cryopreservation?
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Embryo
Cryopreservation
Embryo cryopreservation or embryo freezing is a method used
to preserve embryos by cooling and storing them at low temperatures.
They can then be thawed at a future date and transferred to
the uterus, providing additional opportunity for achieving
conception.
As part of the usual process of In Vitro Fertilization, multiple
eggs may be stimulated to grow, be recovered from the ovary
and become fertilized. This may result in additional embryos
in excess of the number that a couple would desire to have
transferred back to the uterus at one time. If the additional
embryos are of sufficiently good quality to undergo the process
of cryopreservation, this can be performed in order to provide
another opportunity for embryo transfer. That is, if the IVF
fresh embryo transfer does not result in pregnancy, the frozen
embryos can be subsequently thawed and transferred to the
uterus in either a natural menstrual cycle or a hormonally-controlled
cycle. Alternatively, if the IVF cycle is successful, the
embryos can be stored for several years should the couple
decide to attempt to have more children. NewLife will store
embryos with annual renewal of a cryopreservation agreement.
Worldwide, cryopreservation of human embryos has been shown
to be a successful procedure and there are no reports of increased
birth defects in pregnancies achieved through this process.
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Semen
Cryopreservation
Sperm from two sources can be frozen:
from ejaculates or from fluid extracted in the operating room
during surgical procedures (vasal, epididymal and testicular
sperm specimens). The sperm is usually frozen for a period
of one year; at that time, future arrangements are discussed.
It is generally believed that sperm that have been through
the freeze-thaw process are no more likely to result in birth
defects than freshly ejaculated sperm. |
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