6. In vitro fertilization (IVF)
involves chemically inducing several follicles to develop at the same time in
the ovaries, surgically removing several of the resulting eggs, then fertilizing
them with sperm in a culture dish. After several days, the resulting embryos
are at about the 8 cell stage. At this point, one is transferred back to the
mother's uterus where it will hopefully implant. Any extra fertilized eggs can
be frozen for use at a later date.
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Slichter