FINAL LEC 4: Reproductive Technologies

Question 1

-When the savior child is born, its umbilical cord blood can be saved as a source of stem cells for the patient inneed ofa transplant
➔ First case: Led to the birth of_____

Answer 1

SAVIOR SIBLING, Adam Nash

Question 2

Inability to conceive a child after a year of frequent sexual intercoursewithout the use of contraceptives

Answer 2

INFERTILITY

Question 3

➔ Delay in conceiving
➔ The possibility of conceiving naturally exists, but exists, but takes longer than average

Answer 3

SUBFERTILITY

Question 4

➔ Start at menopause (_____), only a thousand or so oocytes remain inher ovaries
➔ Incidence of pregnancy-related problems rises with maternal age, including chromosomal anomalies, fetal deaths, premature births, & low birth-weight babies

Answer 4

AS WOMAN AGES, FERTILITY DECLINES, Age 51

Question 5

➔ Are at increased risk of having children who develop autism& schizophrenia
➔ Spermmotility declines with age of the man

Answer 5

OLDER MEN

Question 6

➔ Condition in which a man has a low sperm count (fewer than the average 15-200 million spermcells permLof ejaculate
➔ Causes: hormonal imbalance; man’s IgA antibodies that cover the sperm; varicose vein in the scrotum

Answer 6

OLIGOSPERMIA

Question 7

Condition in which there’s no measurable spermin aman’s ejaculate (semen)

Answer 7

AZOOSPERMIA

Question 8

➔ ⅓ of infertile man have small deletions of the Y chromosome that remove the only copies of key genes whose products control spermatogenesis
➔ Mutations in genes that encode androgen receptors or protein fertility hormones, or that regulate sperm development or motility.
● To speed conception, amanwith lowspermcount can donate several semen samples over a period ofweeks at a fertility clinic.
● Men with spinal cord injury can use a vibrating device applied to the tip of the penis or inserted into the rectum
● Spermquality ismore important than quantity

Answer 8

GENETIC CAUSES

Question 9

Cause: abnormalities in any part of the reproductive system

Answer 9

FEMALE INFERTILITY

Question 10

tumor in the ovary or in the pituitary gland in the brain, underactive thyroid gland, or use of steroid-based drugs (cortisone)

Answer 10

Hormonal imbalance

Question 11

➔ Too fewoocytes
➔ Signs: ovary with too few follicles (observed on an ultrasound scan) or elevated levels of follicle-stimulating hormone in the 3rd day of themenstrual cycle

Answer 11

Reduced ovarian reserve

Question 12

➔ Prevent spermfromreaching an oocyte
➔ Entrap a fertilized ovum
➔ Tubal or ectopic pregnancy
➔ Can be opened by surgery

Answer 12

Uterine tubes blockage

Question 13

➔ Fibrosis
➔ Endometriosis

Answer 13

Excess tissue growing in the uterine lining

Question 14

➔ CERVICAL MUCUS (due to infection) can entrap sperm
➔ VAGINAL SECRETIONS - may be so acidic or alkaline
➔ Too littlemucus can prevent conception
➔ Mucus in a woman’s body sometimes has antibodies that attack sperm

Answer 14

Secretions in vagina & cervix

Question 15

can entrap sperm

Answer 15

CERVICAL MUCUS (due to infection)

Question 16

may be so acidic or alkaline

Answer 16

VAGINAL SECRETIONS

Question 17

They can tell when they are most fertile by suing an OVULATION PREDICTOR TEST which detects a peak in the level of luteinizing hormone. T OR F

Answer 17

TRUE

Question 18

Older way to detect onset evaluation is to record body temperature each morning using digital thermometer with subdivisions of hundredths of a degree Fahrenheit > indicate 0.4-0.6 rise in temperaturewhen ovulation starts. T OR F

Answer 18

True

Question 19

Sperm can survive in a women’s body for up to ____, but the oocyte is only viable for____ after ovulation.

Answer 19

5 days, 24-48 hours

Question 20

➔ Can stimulate ovulation, but can also causewomen to “superovulate”

Answer 20

FERTILITY DRUGS

Question 21

commonly used drug, raises the chance ofhaving twins from1-2% to 4-6%

Answer 21

CLOMIPHENE

Question 22

If a woman’s ovaries are completely inactive or absent (due to a birth defect or surgery)

Answer 22

Can become pregnant only is she uses a donor oocyte

Question 23

★ SPERM COUNT
★ SPERMMOTILITY ★ SPERMMORPHOLOGY
(performed by urologists)
★ Y chromosome deletions
oligospermia - genetic counselor
★ Unidentified cause of infertility - gynecologist checks the thewoman to see that reproductive organs are present &functioning

Answer 23

INFERTILITY TESTS (MEN)

Question 24

Detects the surge in luteinizing hormone (LH) that occurs before ovulation

Answer 24

OVULATION TESTING

Question 25

Detects abnormalities in the uterine cavity

Answer 25

HYSTEROSALPINGOGRAPHY

Question 26

Determines the quality and quantity of eggs available for ovulation

Answer 26

OVARIAN RESERVE TESTING

Question 27

IMAGING TESTS uterine/fallopian tube disease

Answer 27

PELVIC ULTRASOUND

Question 28

IMAGING TESTS used to see details inside the uterus that can’t be seen on a regular ultrasound

Answer 28

SONOHYSTEROGRAM (saline infusion sonogram)

Question 29

IMAGING TESTS Involves collecting cells fromyour cervix

Answer 29

PAP SMEAR

Question 30

IMAGING TESTS Check levels of ovulatory hormones as well as thyroid and pituitary hormones

Answer 30

OTHER HORMONE TESTING

Question 31

IMAGING TESTS May identify endometriosis, scarring, blockages or irregularities of the fallopian tubes, and problems with the ovaries and uterus

Answer 31

LAPAROSCOPY

Question 32

Helps determine whether there’s a genetic defect causing infertility

Answer 32

GENETIC TESTING

Question 33

Procedures that replace a gamete or provide a uterus to help peoplewith fertility problems have children ➔ Can be performed onmaterial from: ★ The parents-to-be (“nondonor”) ★ Donors ★ May be”fresh” (collected just prior to the procedure) ★ “Frozen” (preserved in liquidnitrogen) ➔ Man can be a genetic parent ★ Contributing half of his genetic self in his sperm ➔ Woman can be both ★ Genetic parent - donating oocyte ★ Gestational parent - loaning her uterus

Answer 33

ASSISTED REPRODUCTIVE TECHNOLOGIES (ARTs)

Question 34

➔ Oldest ART (artificial insemination), a doctor places a donated sperm into a woman’s cervix or uterus ➔ A woman might seek IUI using donor sperm: ➢ Her partner is infertile or has a mutation that the couple wishes to avoid passing to their child ➢ To be a single parent without having sex ➢ Lesbian couple to have a child

Answer 34

Intrauterine Insemination (IUI)

Question 35

➔ Surrogate mother agrees to bear a child for another womanwho is incapable to conceive herself by being inseminatedwith theman’s sperm ➔ Both genetic&gestationalmother ➔ Surrogate mother lends only her uterus, receiving a fertilized ovum conceived from a man & a woman who has healthy ovaries, but lack a functional uterus ➔ “Embryo transfer to a host uterus” ➔ “Gestational-nly surrogatemother

Answer 35

Surrogate Motherhood

Question 36

➔ “Fertilization in glass”, sperm&oocytes join in a laboratory dish ➔ A woman might undergo IVF if her ovaries & uterus work but her uterine tubes are blocked ➔ Chances of a live birth following IVF: 20-35%per cycle ➔ Factors that lower the likelihood of success: ★ Maternal age ★ Increased time being fertile ★ Number of previous and failed IVF attempts ★ Use of a woman’s own oocytes rather than a donor’s ★ Infertilitywith a known cause ➔ Embryos resulting from IVF that are not soon implanted in the woman can be frozen in liquid nitrogen (“cryopreserved” or vitrified”) for later use ➢ Cryoprotectant chemicals are used to prevent slats frombuilding up or ice crystals fromdamaging delicate cell parts ➢ Freezing takes free hours; thawing about halfanhour

Answer 36

In Vitro Fertilization (IVF)

Question 37

➔ An infertility treatment that injects a sperm cell nucleus into an oocyte ➔ Helpful formenwho have lowspermcounts ormany abnormal sperm ➔ Makes fatherhood possible for men who cannot ejaculate

Answer 37

Intracytoplasmic sperm injection (ICSI)

Question 38

➔ Oocytes can be stored (freezing) ➔ Reasons to freeze oocytes: ★ Cancer treatment (radiation therapy or chemotherapy) that can harm oocytes & cause early menopause ★ Exposure to toxins or teratogens in theworkplace ★ Disease of the ovaries ★ Premature ovarian failure, which may be due to XO syndrome or fragile X syndrome ★ Ovary removal to prevent ovarian cancer due to a BRCA1 or BRCA2 mutation ★ Inability to obtain viable sperm on the day of IVF ★ Extra oocytes remain after IVF ★ Donation ★ Delaying motherhood for personal reasons ➔ Oocytes are frozen in liquid nitrogen at temperatures below -40C, when they are at metaphase of the secondmeiotic division ➔ Problems: ★ If the spindle comes apart as the cell freezes, the oocyte may lose a chromosome, which would devastate development ★ Retention of a polar body, leading to a diploid oocyte ➔ To minimize risk of damage to oocytes when freezing ➢ They are first treated with crypto protectants that remove water & prevent ice crystal formation ➔ When the frozen oocytes are to be used ➢ They are slowly warmed & rehydrated by gradually removing the crypto protectants ➔ Frozen oocytes are fertilized in vitro using ICSI because the outermost layer (zona

Answer 38

Oocyte Banking (Freezing) and Donation

Question 39

➢ Freezing strips of ovarian tissue that can be stored, thawed, & reimplanted at various sites ➢ The tissue ovulates & the oocytes are collected & fertilized in vitro.

Answer 39

Ovarian tissue cryopreservation

Question 40

➢ Chosenmethod bywomen who have no oocytes or wish to avoid passing on a mutation ➢ Oocyte donors are typically younger women & some women become donors when they undergo IVF & have “extras”

Answer 40

Oocyte donation

Question 41

➔ Often teamed with IVF to detect genetic & chromosomal abnormalities pregnancy starts ➔ Diagnosis: if it detects a specific gene variant known to be in 1 or both parents-to-be ➔ Screening: it is is used to construct a karyotype, without looking for a specific chromosomal anomaly ➔ “Preimplantation” refers to the fact that the embryo is testes at a stage prior to when it wouldnaturally implant in the uterus ➔ Errors happen when a somatic mutations affects the sampled cells but not the rest of the embryo

Answer 41

Preimplantation Genetic Diagnosis

Question 42

➔ ARTs introduce ownership and parentage issues ➔ Another issue: ★ Human genome information is revealing more traits to track & perhaps control in coming generations ★ ARTs operate on molecules & cells, but affect individuals &families

Answer 42

ARTs DISASTERS