human bio chp 14 and some 15

Infertility

Being unable to achieve pregnancy despite frequent unprotected sex over the period of atleast a year

What must sperm be in able to fertilise an egg

Produced in sufficient quantities

Able to move in forward direction

Able to penetrate corona radiate and zona pellucida

→ means there must be high number of sperm produced with correct structure

What factors affect make fertility

Semen and sperm may flow into bladder rather than out urethra

Male’s immune system may develop antibodies for own sperm, altering them and reducing effectiveness

Blockages may occur in male’s reproductive tact, esp vas deference, which may stop sperm leaving testes

Normal imbalance: may affect sex drive and production of sperm

What is the relationship between age and healthy eggs in females

As females get older, number of healthy eggs remaining decreases, greatly reduces chance of pregnancy, esp over age of 36

What is Polycystic Ovarian Syndrome (PCOS)

Hormonal condition where ovaries contain many partially formed follicles, that fail to mature.

Means eggs are not realised and therefore cannot be fertilised.

What is Hyperprolactinemia?

High levels of hormone prolactin, may occur in people with pituitary tumours, hypothyroidism, and PCOS.

High levels of prolactin results in intermittent or lack of ovulation.

How does menopause cause infertility

Once female goes through menopause, no longer ovulating.

Some females menopause before age of 49, therefore unable to get pregnant from this time.

Early menopause or primary ovarian insufficiency.

How does cancer treatment affect ovulation

May cause primary ovarian insufficiency, hence infertility.

In woman younger than 30, may be temporary, and may become fertile again after treatment,

Older the woman, less likely it is that her fertility will return

What is endometriosis

Affects ~10% of women.

Painful condition where cells of endometrium grow outside uterus, resulting scar tissue or distortion of uterine tubes affect fertility by blocking eggs release or pathway through to uterus

What are fibroids and how do they affect fertility

Fibroids are being growths in muscular part of uterus.

Very common

Only affects fertility if location distorts uterine cavity or blocks uterine tubes.

How do blockages of the uterine tube affect fertility?

Stop the egg pass8ng through to uterus,

Can occur following infections: gonorrhea, chlamydia, or damage (like from ectopic prey)

How do problems with the menstrual cycle affect fertility?

Because it Influences implantation of blastocyst

Hormonal imbalance a

Can reduce development of endometrium and its maintenance

How does microsurgery solves some problems of infertility?

Blocked uterine tubes and sperm ducts can be open

Fibroids or endometriosis can be removed

How does ovulation tracking help with fertility?

Possible to identify time when female most fertile through series of blood tests.

→ surge in Lute using hormone prior to ovulation.

Sperm lasts 2-3 days, egg only 1, so crucial to inseminate prior to ovulation, and have intercourse.

What is ovulation induction

Some problems of fertility are bcs of low levels of hormones.

Medication used to correct problem.

What types of medication is used to correct this problem?

Clomiphene stimulates body to make more FSH (follicle stimulation hormone)

Hormone injections of FSH increase blood levels of the hormone

Human Chorionic gonadotrophin (hCG) used to trigger ovulation once follicle has matured.

How can hyperprolactinemia be solved?

Prolactin levels need to be lowered so ovulation can occur,

Oral medication available to restore normal levels of prolactin.

What is Artificial insemination?

Aka IUI.

Process where sperm is released into uterus by catheter being inserted through cervix.

Sperm sample then injected through catheter.

From uterus sperm able to move naturally through uterine tubes where may fertiliser an egg.

IUI increase number of sperm that reach uterine tubes.

Who can benefit from IUI

Males with low sperm count or decreased motility

Ejaculation dysfunctions

Sperm stored and frozen due to males absence or needing to undergo treat ment (chemo, radio)

Females with cervical scarring

Hostile cervicle mucus

Same sex couples

Single females

What is Gamete intrafallopian transfer?

GIFT

procedure performed when there are normal uterine tubes and adequate sperm.

What is the procedure of GIFT

1. Hormonal treatment used to stimulate female to produce more than 1 egg

2. Sperm & egg collected and analysed

3. Sperm & egg mixed together in laboratory

4. Sperm & egg mixture injected into woman’s uterine tubes during laparoscopic surgery

5. Hoped that sperm will then fertiliser egg naturally and move down uterine tubes before implanting in uterus

What are some disadvantages to GIFT

Lower pregnancy rate and requiring surgery

But as fertilisation occurs naturally method is preferred by some couples bcs of religious or ethical reasons

Who does In Vitro Fertilisation (IVF) help?

Used to overcome range of fertility issues (blocked uterine tubes, ovulation disorders, endometriosis, fibroids, low sperm quality or production and unexplained.)

What is hormonal treatment in IVF used for?

• stimulate ovaries so multiple follicles develop

• Control ovulation

• Prepare uterine lining

How does IVF work?

Series of blood tests and ultrasounds used to monitor development of follicles,

When eggs mature, collected by needle passing through vagina to ovaries

Following retrieval, eggs mixed with sperm at 37 degrees.

~ 2-6 days after collection, embryo is inserted into uterus via catheter passed through cervix.

What is Intracytoplasmic sperm injection.

helps with sperm problems.

Once eggs collected, examined to ensure suitable.

Sperm then injected into egg, achieving fertilisation.

Resulting cells then monitored and any thầy are developing normally able to be inseminated

What are some concerns about ICSI

bcs I fertility could be due to genetic disorder, the Genetic defect may be passed on to offspring.

Therefore children recommended to be examined by paediatrician.

It is possible for male to undergo genetic testing, if defect found, other options considered.

What is surgical sperm retrieval

Some men unable to ejaculate, or very low numbers of sperm released,

Sperm may be collected during surgery to be used in IVF & ICSI

Surgery may be performed under local or general anaesthetic

Needle used to collect sperm from epididymis or testis

What are donor gametes or embryos

Possible to use eggs, sperm or embryos from donors to achieve pregnancy

Donor may be known to couple or anonymous.

What is surrogacy?

if female unable to conceive or carry baby, another woman carries child for duration of pregnancy and then gives child to couple to raise as their own.

How does surrogacy work?

Achieved by artificial insemination of father’s gestational surrogacy, where IVF used to produce an embryo, then I steered into surrogate.

Hatnhappens to unused embryos

They are frozen and kept indefinitely.

They can be disposed, donated ( other ppl or research)

What are some barriers to assisted reproductive technologies

1. Ethical and religious beliefs

2. Cost

→ requires specialist doctor, Initial tests and screenings, medications, fertility treatments, surgery/hospital cots, access to donor programs, frozen sperm/egg/embryo storage

Medicare can help but out of pocket cost per cycle still high

how does an ultrasound work?

Uses inaudible high frequency sound waves to produce image of foetus.

Probe placed on abdomen of pregnancy women, sound waves refracted by foetal tissues to obtain visual ‘echo’ of inside uterus,

Doctor feeds reflected sounds into computer to produce screen image of foetus for study,

What can an ultrasound be used for?

Monitor growth and development of foetus.

• confirm pregnancy

• Estimating stage of pregnancy

• Determining number of foetuses

• Identifying abnormalities of cervix or uterus

• Monitoring growth of foetus

• Determining gender of foetus

• Genetic screening

• Identify birth defects

Etc…

What can’t an ultrasound do?

Cannot diagnose all abnormalities

If abnormality detected, further tests may be required for more specific information

How does genetic sampling take place?

Foetal cells obtained for analysis using either amniocentesis or chronic villus sampling.

Tests used to examine foetus’s chromosomes to detect Fr rive, missing or additional chromosomes

What is amniocentesis?

Carries out between 16th-20th weeks of pregnancy

Involves suing ultrasound to guide needle through abdominal wall 8th amniotic cavity,

~10-20mL of fluid removed.

Living cells from foetus floating in fluid, can be examined for biochemical defects and abnormalities in number of chromosomes or in chromosome structure

What are some risks of amniocentesis?

Small risk of infection, miscarriage or damage to baby

Therefore, only performed on women who are thought to be at higher risk of delivering child with birth defect.

What birth defects can be seen using amniocentesis?

Down syndrome, cystic fibrosis, neural tube defects (spina bridal), duchesse muscular dystrophy, sickle cell disease

How does chorionic villus sampling work?

Obtains specimen of foetal cells from chorion.

Cells examined in similar way to amniocentesis

Testing around 9-19 weeks of pregnancy

What are some disadvantages and advantaged to chorionic villus sampling?

Risk of miscarriage following procedure is 2%

Foetal tissue gained through CVS can be tested more quickly than specimen of amniotic fluid.(important of birth defects may require termination)

Can be used to detect genetic disorders and biochemical abnormalities (not spina bfida)

How do blood tests work?

Blood test of mother’s blood, non-invasive prenatal test. (Possible bcs some foetus DNA may pass into mother’s blood)

SCREENING NOT DIAGNOSIS

Can see if there is increased chance of baby having certain disorder.

Available from 10 weeks of gestation.

What can blood tests screen for?

Down syndrome (trisomy 21)

Edward’s syndrome (trisomy 18)

Patan syndrome (trisomy 13)

Turner syndrome

What is foetal monitoring?

Regular recoding of baby’s heart rate in order to detect indicators of stress

Usually takes place during labour and birth using ultrasound and electrocardiography

What is electrocardiography?

Procedure for recoding electrical changes in the heart.

Records as electrocardiogram

What is an electrocardiogram?

Shows series of waves that relate to electrical impulses that occur during each beat of heart.

Results printed on paper or displayed on monitor

What is the aim of foetal monitoring?

Identify any risk of injury to foetus so appropriate action taken.

Detailed foetal heart rate analysis enables medical staff to check wether any risk of oxygen deficiency occurring.

What cam oxygen deficiency do?

Brain damage or stillbirth

What is a fetoscope?

Instrument used to gain information about foetus in uterus,

2 types stethoscope and fibre-optic scope

Can be used during foetal surgery as well

What does a stethoscope do?

Listens to foetus’s heartbeat

What does a fibre-optic scope do?

Looks directly at foetus’s through small telescope-like instrument.

Introduced to foetus through abdominal wall

What does the examination of the outward appearance of the foetus enable?

Detection of conditions like cleft lip and palate, missing or abnormal ears, deformed or absent limbs, and spinal abnormalities.

Early detection can allow for termination,

What does foetal blood sampling do?

Diagnose chromosomal abnormalities

Diagnose foetal anaemia

Check foetal oxygenation

Identify infections

Give medications

Where can this blood be taken from?

Umbilical cord- percutaneous umbilical cord blood sampling (needle inserted through abdominal wall and uterus into umbilical vein

Foetal blood vessels- usually liver or heart via fetoscope

What are some risks of foetal blood sampling

Risk of miscarriage higher 1-2%

Risk of infection, blood loss and premature rupture of amniotic sac

What is biochemical analysis?

Assessment of marker proteins occur with all newborns in Aus.

What can biochemical analysis detect?

Phenylketonuria (PKU), by testing blood for excessive amounts of phenylalanine or by analysing urine for phenylpyruvic acid.

Alpha-fetoprotein (AFP) measured in samples of amniotic fluid, concentration of protein very high when foetus has malformation of spinal cord.

What do DNA probes enable?

Detection of range of genetic disorders.

What are are the probes based on?

Based on recombinant DNA technology.

Segment of DNA used that is structurally identical to gene being tested.

Some units of DNA segments are ‘labelled’ with dye or radioisotope.

DNA probes then joined to gene in question

If gene is normal, then DNA probe joined with DNA segments with which it is structurally identical, shows them up.

If abnormality gene, does not show up, is identifiable as gap in DNA being tested