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Chapter 21 Reproductive Technologies. BY: Jessica Carvalho Eric Herman Dorathy Osaro-Igwe Lauren Reykdal. What is Infertility/Subfertility. Infertility – Individuals that cannot conceive a child within one year of trying
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Chapter 21 Reproductive Technologies BY: Jessica Carvalho Eric Herman Dorathy Osaro-Igwe Lauren Reykdal
What is Infertility/Subfertility • Infertility – Individuals that cannot conceive a child within one year of trying • Subfertility – Individuals that can conceive a child, but it takes longer than one year to be successful • 1 in 6 couples face complications with conceiving a child or giving birth Common causes of Subfertility and Infertility in both Men and Women
Male Infertility/Subfertility • Facts • 1 in 25 men is infertile • Most cases are genetic • Cause - Low sperm count Treatments include hormone therapy, surgery and avoiding excess heat • Cause - Immobile sperm due to abnormal sperm shape, infection, malfunctioning prostate, deficient apoptosis • Abnormally shaped sperm • Treatments include intracytoplasmic sperm injection, antibiotics and hormones • Cause- Antibodies against sperm due to immune system problems • No listed treatment in textbook
Female Infertility/Subfertility • Cause – Erratic ovulation due to pituitary or ovarian tumor, underactive thyroid or polycystic ovary syndrome • Treatments include hormone therapy, surgery and avoiding excess heat • Cause –Antisperm secretions (cause unknown) • Treatments include acid or alkaline douches, estrogen therapy • Cause - Blocked uterine tubes due to infections caused by IUD, abortion, or by STD • Treatments include laparotomy, oocyte removed from ovary and placed in uterus • Cause - Endometriosis (cause unknown) • Treatments include hormones, laparotomy, drugs • Fact • Infertility chances increase with age Areas of reproductive problems
What Happens After A Year? Infertility Tests • First • Male is checked • It is easier, less expensive, and less painful • Sperm count, motility and shape of sperm are checked • Urologists can perform sperm tests • Second • Female is checked • Reproductive structures are checked to ensure they are present and functioning • Gynecologists usually perform this check first Hint “A woman is most fertile during ovulation and 1 to 2 days before ovulation”, (WebMD) Some couples are simply missing the opportunity
Next Step Assisted Reproductive Technology (ART) “Procedures that replace a gamete or the uterus to help people with fertility problems have children”, (Human Genetics) • Facts • “In the United States, about 1 percent of the approximately 4 million births a year are from ARTs”, Human Genetics • “ART births account for 0.4 percent of single births”, Human Genetics Table 21.3 shows various Assisted Reproductive Technology (ART)
Donated Sperm Intrauterine Insemination (IUI) • Oldest assisted reproductive technology • Donation by a man of his semen to achieve a pregnancy and produce a baby in a woman who is not the man's sexual partner • The first donated IUI in humans was done in 1790 • Donation may be stored at a sperm bank or through a third party sperm agency • Commonly assists heterosexual couples unable to reproduce because of 'male factor' fertility problems • Increasingly used as a means to enable single women (termed choice mothers) • Problem • Possibility of inheriting a disease
Donated Uterus Surrogate Mother • Involves the organ of the female human in which the embryo develops • Situated between the bladder and rectum and is connected to the fallopian tubes and to the vagina • When the child is born, the surrogate mother gives up the baby • Attorneys usually arrange surrogate relationships to avoid future misunderstandings and problems that may arise • Problems • Surrogate mother may not be able to predict her responses to pregnancy and childbirth • If a surrogate mother changes her mind about giving up the baby, the results are devastating to the recipients
In Vitro Fertilization (IVF) Intracytoplasmic sperm injection (ICSI) Enables some infertile men, men with spinal cord injuries, or men with certain illness to become fathers. A single sperm cell is injected into the cytoplasm of an oocyte. • Relatively simple and painless procedure • Often the best alternative to achieve pregnancy • Involves collecting eggs and sperm from both partners and placing them together in a laboratory dish for fertilization • Days later the microscopic embryos are transferred into the uterus where implantation and pregnancy will hopefully occur, as in a normal pregnancy • Problem • IVF may fail because of the artificial environment for fertilization Fact Louise Joy Brown was the first test tube baby that was born in 1978. Since her birth, about 1 million children have been born through the process.
Gamete Intrafallopian Transfer, GIFT • Improves the fertilization setting • It is a tool of assisted reproductive technology against infertility. Eggs are removed from a woman's ovaries, and placed in one of the Fallopian tubes, along with the man's sperm • The technique, which was pioneered by endocrinologist Ricardo Asch, allows fertilization to take place inside the woman‘s body Zygote Intrafallopian Transfer, ZIFT • This procedure is where IVF ovum is introduced into the woman’s uterine tube. Allowing the ovum to make its own way into the uterus • Increases the chance that it will implant
Oocyte Banking and Donation • Candidates include people who want to have a child later in life and are exposed at a young age to chemicals, toxins and teratogens (usually through chemotherapy during cancer treatment • Strips of ovarian tissue can be frozen, stored, thawed, and re-implanted at various sites in the body to avoid the difficulty of freezing oocytes • Probability of pregnancy using a frozen oocyte with current technology is around three percent • Only one hundred babies have been born using frozen oocytes, (At print time of this book) • Problems • Ice crystals can form during the freezing process because the oocyte contains a large volume of water • Also, the retention of a polar body leads to a diploid oocyte • Donation • Women can also get oocytes from donors. Donors are typically young, healthy women. While oocyte donation is much less common than sperm donation, it is becoming more common. The procedure costs at least $10,000
Preimplementation Genetic Diagnosis (PGD) • Detects genetic and chromosomal abnormalities before pregnancy starts • One cell, or blastomere, can be removed for testing from an 8-celled embryo and the remaining 7 cells can complete development normally in the uterus. The cell that is removed is karyotyped, or its DNA amplified and probed for genes that the parents carry. The embryos that pass the chromosomal check are selected for implantation or stored • Accuracy is about 97 percent. The first children who had preimplantation genetic diagnosis were born in 1989. In 1992, the first child was born who underwent PGD to avoid a specific inherited disease (cystic fibrosis.) • Problems • Seen as a bioethical “slippery slope.” PGD is used solely for family planning and is not meant to help people control the sex of their child. Human nature can get in the way. (Medicine endorses the use of PGD for sex selection only to avoid passing on an X-linked gene.) PGD is a very controversial subject, even when used to avoid diseases
Extra Embryos • After assisted reproductive technologies are performed, “extra” oocytes, fertilized ova, and early embryos are left over. • Human prenatal development cannot complete outside of a uterus, so decisions must be made as to what will happen to these biological materials • Clients of fertility facilities can either allow their oocytes, fertilized ova, or embryos to be stored indefinitely or discarded, donate them to other infertile couples, or donate them for use in research • Extra embryos are another controversial topic • Current Example • The case of Nadia Suleman, the mother of 14 who recently birthed octuplets after being implanted with all of her extra embryos. Nadia felt that discarding her embryos was morally wrong, and decided to give every embryo a chance at life. This created a national uproar and had a lot of people questioning whether Nadia’s choice was ethical or not
References American Society for Reproductive Medicine, http://www.asrm.org/ (Last accessed on July 13, 2009) Lewis, Ricki. (2009) Human Genetics: Concepts and Applications Eighth Edition. McGraw-Hill, New York, NY. WebMD, http://www.webmd.com/infertility-and-reproduction/tc/infertility-tests-overview (Last accessed on July 14, 2009) U.S. Department of Health & Human Services, http://www.womenshealth.gove/FAQ/infertility.cfm (Last accessed on July 12, 2009) Wikipedia, http://en.wikipedia.org/wiki/Infertility (Last accessed on July 13, 2009)