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Assisted Reproductive Technology (ART) and Application Yu-Hui Tsai, Ph.D. Graduate Institute of Medical Sciences Taipei Medical University

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Assisted Reproductive Technology (ART) and

Application

Yu-Hui Tsai, Ph.D.

Graduate Institute of Medical SciencesTaipei Medical University

Infertility

• Couple who does not use any contraceptive, but can not conceive within 2~3 years are considered infertile.

• Up to 5,000,000 American couples suffer from infertility every year and 20% of those decide to undergo in vitro fertilization.

• About one out of every 6 couples is infertile in the US, and Taiwan as well.

Male infertility

• Infertility due to male factor accounts for at least 40% of infertility cases. For this reason, it is very important that men also be investigated for fertility problems. While blockages and problems producing healthy sperm are often the main reasons for male infertility, there are a variety of issues that can diagnosed.

• Once a diagnosis has been made by a fertility specialist, a proper course of treatment can be recommended. Depending on the cause of male infertility, possible forms of treatment may include surgery, drugs, or assisted reproductive technologies, like ICSI.

Decreasing male fertility rates

• Recent studies have identified several factors causing a decline in male fertility:

• The anti-impotence drug Viagra could be damaging sperm acrosomes, and lowering the taker’s ability to conceive (40% less). (Fertility and Sterility).

• Another study suggests that pollution from chemicals such as dioxin can lower a man's sperm count. (in the environmental journal the Ends Report)

• Endocrine-disrupting chemicals are also thought to be affecting fertility rates.

Menevit, the 'first ever drug for male infertility',

• Menevit, developed in Australia, contains antioxidants which works by acting on free radicals that fragment sperm, the main cause of infertility.

• In a preliminary study of 60 infertile men, the rate of pregnancy was increased significantly, but larger clinical trials are required before the drug can be merited.

Female infertility• Ultrasound is likely to be done first, as this can al

ert your specialist to any possible problems. There are also a number of blood tests that can be performed. In women, the most common ones include:

• Day 3 FSH testing • Luteinizing hormone (LH) testing • Progesterone testing • Estradiol Level testing • Hysterosalpingogram • For women who are suspected of having low ov

arian reserves, a Day 3 Inhibin and a Clomiphene Challenge test may be performed.

• Antibody against husband’s sperm

Treating Infertility: Assisted Reproductive Technology

(ART) • A large percentage of couples face difficulties in

getting pregnant, many have found success with Assisted Reproductive Technology (ART).

• ART involves a number of different procedures to help address fertility problems and increase the likelihood of pregnancy. Be sure to speak with the reproductive endocrinologist about ART procedures that may be right for you to increase your chances of conceiving.

Assisted Reproductive Technology (ART)

• Insemination

sperm collection/ sperm donation

• In vitro fertilization

egg retrieval/ egg donation

• Surrogate

Who needs IVF?

• Couple has infertility problem.– Men with low sperm count, abnormal sperm, no

mature sperm, antibody against sperms etc.– Women with oviduct obstruction, endometriosis,

endocrine imbalance, reproductive organ infection, antibody against partner’s sperms etc.

• The couple both carry recessive genetic disorder on the same genetic locus, or female with X-linked genetic disorder .

In vitro fertilization (IVF) ( 試管嬰兒 )

In vitro fertilization (IVF) ( 試管嬰兒 )

• IVF is the uniting of egg and sperm in vitro (in the lab). Subsequently the embryos are transferred into the uterus through the cervix and pregnancy is allowed to begin.

In vitro fertilization (IVF) ( 試管嬰兒 )

• IVF is a major treatment in infertility when other methods of assisted reproductive technology have failed. The process involves – ovulation induction through hormone treatment,– monitoring of hormone levels and follicle scans with

ultrasound, – egg retrieval from the woman's ovaries – and fertilize eggs with sperms in a fluid medium.

• The fertilized egg (zygote) is then transferred to the patient's uterus with the intent to establish a successful pregnancy.

Procedures for IVF• Day 0 Egg retrieval, Sperm collection, and prepa

ration • Insemination in vitro• Day 1 Check eggs for fertilization (the presence

of two pronuclei or PN's)• Day 2 Embryos at the 4-cell or more stage of de

velopment• Day 3 Embryos at the 8-cell or more stage of de

velopment• Day 4 Embryos at the compacted morula (16-32

cell) stage• Day 5 Embryos at the blastocyst stage of develo

pment

Inducing Superovulation

• Injections of Lupron, Metrodin, Pergonal or Humegon allow the ovaries to develop many follicles as seen in this ultrasound immediately prior to egg retrieval.

Human MI oocyte with extruded polar body

Human MII oocyte

Human MII oocyte with prominent spindles

Fertilization of retrieved egg• Retrival of maturing eggs via laparoscopy.• Each egg is incubated with > 3.5 x 106 sperms. T

he fertilized egg contains two pronuclei. Each contains half the chromosomal material from each one of the genetic parents.

Embryo at 4-cell stage

• A four cell pre-embryo. Each of the cells is called a blastomere. The embryo is surrounded by a protein matrix "shell" called the zona pellucida.

Transferring of 8 cell-stage embryo

• On the third day after egg retrieval eight cell pre-embryos can be transferred to the uterus. On average, 15 to 25% of embryos will implant after being transferred.

Hatching in vivo prior to implantation

• Prior to implantation, the pre-embryo, now at the blastocyst stage, must hatch out of the zona pellucida prior to implantation.

Intracytoplasmic sperm injection (ICSI)

Intracytoplasmic sperm injection

• Intracytoplasmic sperm injection (ICSI, pronounced "eeksee") is an in vitro fertilization procedure in which a single sperm is injected directly into an egg.

• This procedure is used to overcome male infertility problems, although it may also be used where eggs cannot easily be penetrated by sperm, and occasionally as a method of in vitro fertilization, especially that associated with sperm donation.

How is ICSI performed?• Using micromanipulation technology, ICSI

allows fertility specialists to fertilize an egg using just one sperm. While it is preferred to use sperm from a semen sample, specialists can retrieve sperm from the testicles if it is necessary. Once sperm has been collected, the specialist will draw a single sperm into a needle and inject it directly into an egg that has been collected from the female partner through the usual retrieval methods.

• This process bypasses the conventional IVF methods of fertilization, thereby ensuring that fertilization has taken place. The fertilized eggs are then left to culture for a few days before being transferred back to the woman’s uterus. ICSI is always used alongside IVF.

                                                                                                    

                   

Intracellular sperm

injection (ICSI)

Who needs ICSI?• Men who have very poor semen quality or az

oospermia should be offered ICSI.

– Low sperm count – Poor sperm motility – Abnormally high amount of morphologically atypi

cal sperm – Experienced fertilization failure for unknown reas

ons in a previous IVF cycle – Lack of any sperm in ejaculate due to CAVD, faile

d vasectomy reversal, failure to produce sperm, or an obstruction in the epididymus due to past inflammation

– Retrograde ejaculation – Immunological factors

Gamate/embryo transfer

• Many of the large programs have attempted blastocyst culture, but returned to day 3 transfers because they had trouble getting the embryos to grow the blastocyst stage. Growing the embryos to the blastocyst stage requires great attention to detail - a luxury not afforded in a big program performing dozens of procedures a day.

• Programs performing less than 200 cycles per year have had the best luck with blastocyst culture and transfer with reported (but unverified) pregnancy rates in the 50-70% range for younger patients and egg donor cycles.

Gamete intrafallopian transfer

• In gamete intrafallopian transfer (GIFT), eggs are removed from the woman, and placed in one of the fallopian tubes, along with the man's sperm. This allows fertilization to take place inside the woman's body. Therefore, this variation is actually an in vivo fertilization, and not an in vitro fertilization.

Zygote intrafallopian transfer

• Zygote intrafallopian transfer (ZIFT) is an infertility treatment where a blockage in the fallopian tubes are the cause. Egg cells are removed from a woman's ovaries, and in vitro fertilized. The resulting zygote is placed into the fallopian tube by the use of laparoscopy.

IVD: ivfed eggs developed in vivo• A device that allows IVF embryos to develop in t

he womb rather than a laboratory dish, developed by Swiss company Anecova, is to be trialed at CARE Fertility in Nottingham. 

• The treatment, named in vivo development, or IVD, has been termed a more natural alternative to IVF and there are hopes that it will lead to fewer embryos with genetic abnormalities being produced.

• In normal IVF eggs are fertilized with sperm and allowed to grow for a few days in a laboratory dish containing chemicals and nutrients, before being transfered into the woman's womb for implantaton.

The creation of 'female' sperm and

'male' eggs • If this technological breakthrough ever comes

about, it is suggested that such artificial gametes could offer the possibility of genetic reproduction to people in same sex relationships.

• In fact artificial gametes offer people to have genetically related offspring regardless of age, gender, relationship status or sexuality. Women could use the technique to produce eggs even after having gone though the menopause.

• Individuals who cannot find reproductive partners could even use artificial gamete technology to create complementary gametes from their own bodies to fertilize their 'natural' sperm or eggs.

Applications of ART

• Endanger species• Assisted reproductive technology, allows in vit

ro fertilized (IVFed) embryos for preimplantation genetic screening (PGS) evaluation. The is not used to look for a specific disease but a technique to identify embryos at risk.

The End

Thank you!!