1. Ovulation
induction: This is the process of using ovulation drugs or “fertility
drugs” to stimulate the ovaries to produce several mature eggs rather than
the single egg that normally develops each month. The medications are usually
given as daily injections for a period of 7 – 10 days. During ovulation
induction, ultrasounds are performed to monitor follicle development, and
blood samples are obtained to measure hormone levels. When ultrasound
indicates that follicles are mature, and injection of hCG is given to trigger
ovulation.
2. Egg
retrieval: Once the follicles are mature, the egg must be retrieved.
This is accomplished by transvaginal ultrasound htmliration. This is a
procedure in which a trans-vaginal ultrasound is used to guide the needle
htmliration of eggs from the ovaries. Although the procedure takes only a few
minutes, anesthesia is administered for greatest patient comfort.
3.
Fertilization: Once the eggs are retrieved, they are examined in the
laboratory. Sperm is then mixed with the eggs in specially designed
culture media to enhance the chance that the eggs will fertilize.
4. Embryo
Culture: After fertilization is confirmed, the embryos are cultured for
several days. Embryos are observed and graded as to the level of progression
and growth to determine whether they are suitable for transfer to the uterus.
5. Embryo
transfer: When the embryo has grown to a certain stage, it is placed
into the uterus. The embryo transfer is accomplished by using a special
catheter and technique that utilizes ultrasound to guide the proper placement
of the embryos. The number of embryos chosen to replace depends upon several
factors including the patient's age and the quality of the embryos. Our goal
is to replace two high quality embryos for most patients, but individualized
decisions are made in conjunction with the couple.
6. Embryo
cryopreservation: Excess embryos may be saved for transfer at a later
date by freezing and storing them in liquid nitrogen. Through many years of
research, techniques for freezing (cryopreservation) have been developed that
allow for survival of at least 75% of embryos when they are thawed. The
pregnancy rates from frozen thawed embryo transfers now approach those for
fresh embryo transfers. Babies born as a result of frozen-thawed embryo
transfers have no increased risk of birth defects or other problems.
7. Pregnancy
testing: Ten days after the embryo transfer a blood pregnancy test is
done. If the test is positive, further pregnancy monitoring is planned until
ultrasound establishes the presence of a viable intra-uterine pregnancy. Then
the patient is referred back to their OB-GYN.
8. Assisted
Zona Hatching: As the embryo develops in the uterus it eventually
reaches a point (approximately 5-7 days after fertilization) where it must
escape from the shell (zona pellucida) it has been surrounded by since it was
an oocyte. This process is termed hatching. There is some evidence that
certain individuals may improve their chances of success through IVF if the
zona is artificially hatched prior to embryo transfer. Two main techniques are
used to assisted hatch embryos – both require embryo micromanipulation under
the microscope. The first is a mechanical approach whereby glass needles are
used to the pierce and then create a “tear” in the zona. The second, more
common, approach is to use an acidified culture medium applied to a small area
of the zona via small glass pipettes to etch a hole in the zona. With either
method, the artificial hole is allows easier exit of the embryos from the zona.
This technique is most commonly used for patients that are of somewhat
advanced reproductive age (>35).
