gonodotropin releasing hormone

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In Vitro Fertilization
Hariom Yadav1, Shalini Jain1 and Mukesh Yadav2
1Animal Biochemistry Division,
National Dairy Research Institute,
Karnal-132001, Haryana, INDIA
2SOS in Chemistry, Jiwaji University,
Gwalior-474011, M.P., INDIA
Corresponding author: Email: yadavhariom@gmail.com
Female reproductive system
Male reproductive system
Normal Fertilization
IVF: In vitro fertilization
In vitro: in glass
Fertilization: Ova + Sperm
Basic Principle of IVF
Hormonal
treatment
Female
Harvest
the ovum
Mature Ova
Mix in a test tube
Keep to
develop
embryo
Motile sperms
Collect semen
Natural
ejaculation
Male
Transfer
to mother
Hormonal Treatments
Drugs currently in use include:
• clomiphene citrate (Clomidâ, Seropheneâ)
• human menopausal gonadotropin (hCG)
• gonodotropin releasing hormone (GnRH) analog called leuprolide
(Lupronâ)
Most of these drugs may be used alone or in a combination with
others.
Egg Harvest
1. Ultra Sound Guided Aspiration
2. Laproscopy
Fig 1
Oocytes with
granulosa cells
"Naked" Oocyte
8-cell embryo for transfer
Blastocyst for transfer
Implantation
Fourteen Days after Initial Cell Division
Viable Fetus
After Birth
Alternates of IVF
Gamete intrafallopian transfer (GIFT): GIFT is similar to IVF. It is used when a
woman has at least one normal fallopian tube. Eggs are placed in this tube
along with a man’s sperm to fertilize there.
Zygote intrafallopian transfer (ZIFT): ZIFT is tubal embryo transfer in which a
woman’s eggs are taken from her ovaries, fertilized in the laboratory, and put
back in the fallopian tubes rather than the uterus.
Assisted fertilization techniques when not enough sperm are available or sperm
quality is not sufficient to fertilize include the following:
•
•
•
•
Partial zona dissection
Subzonal sperm injection
Intracytoplasmic sperm injection
Embryo cryopreservation (frozen fertilized egg and sperm)
ICSI
Stands for intracytoplasmic sperm injection. This process is used to inject
a single sperm into each egg before the fertilized eggs are put back into the
woman's body. The procedure may be used if the male has a low sperm
count.
Cryopreservation of Ova, Sperm and Embryo
Risks
Superovulation Stimulates Egg Development
Ovarian Hyperstimulation Syndrome (OHSS)
1. There may be a failure to recover an egg because:
- follicles that contain mature eggs may not develop in the treatment cycle
2. - ovulation has occurred before time of egg recovery
- one or more eggs cannot be recovered
- pre-existing pelvic scarring and/or technical difficulties prevent safe egg recovery
3. The eggs that are recovered may not be normal;
4. There may be insufficient semen to attempt fertilization of the recovered eggs
because the man is unable to produce a semen specimen, because the specimen
contains an insufficient number of sperm to attempt fertilization, because the
laboratory is unable to adequately process the specimen provided, or because the
option to use a donor sperm as a "backup" was declined;
5. Fertilization of the eggs to form embryos may fail even when the egg(s) and sperm
are normal;
6. The embryos may not develop normally or may not develop at all. Embryos that
display any abnormal development will not be transferred;
7. Embryo transfer into the uterus may be difficult/impossible, or implantation(s) may
not occur after transfer, or the embryo(s) may not grow or develop normally after
implantation;
8. Any step in the IVF-ET process may be complicated by unforeseen events, such as
hazardous or catastrophic weather, equipment failure, laboratory conditions,
infection, human error and the like.
Normal results
Success rates vary widely between clinics and between physicians performing the
procedure and implantation does not guarantee pregnancy. Therefore, the procedure
may have to be repeated more than once to achieve pregnancy. However, success rates
have improved in recent years, up from 20% in 1995 to 27% in 2001.
Abnormal results
An ectopic or multiple pregnancy may abort spontaneously or may require termination if
the health of the mother is at risk. The number of multiple pregnancies has decreased in
recent years as technical advances and professional guidelines have led to implanting of
fewer embryos per attempt.
Ethics
• Bypassing the natural method of conception.
• The creation of life in the laboratory.
• Fertilization of more embryos than will be needed.
• Discarding of excess embryos.
• Unnatural environment for embryos.
• Use of untested technology.
• Not affordable for many.
• Misallocation of medical resources.
• Creation of embryos, then freezing them, and keeping them "in limbo".
• Exposure of embryos to unnatural substances.
• Destruction of embryos in research.
• Potential to create embryos for medical purposes.
• Potential to select embryos (PGD).
• Potential to modify embryos.
• Facilitation of the idea that embryos are commodities.
• Financial rewards for IVF doctors dissuade them from recommending
other methods to couples.
• Infertility is treated as a disease and not as a symptom of underlying
medical problems.
Separating the traditional mother-father model
Pregnancy past menopause
Religious objections
Thank you
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