12 - FERTILITY TREATMENTS: INFERTILITY AND ASSISTED REPRODUCTION Flashcards
What is Reproductive Health?
• Reproductive health is defined by 3 measures:
- control
- success
- safety
Control
natural, pharmaceutical, surgical and barrier methods
Success
Potential and Outcome affected by age, general health and previous
pregnancies, social factors, inequalities
Safety
sex and birth are dangerous things: sexually transmitted disease,
infection, problems with delivery and pregnancy, miscarriage.
But risks can be controlled and minimised with good healthcare and education
What is Birth Control?
- Increased reproductive choice links to improvements in ecology, economics, equality and social change.
- Unregulated fertility is a significant contributor to infertility.
INFERTILITY
- Couple is defined as infertile following 12 months of trying to conceive (sex every 2-3 d) (NHS)
- treatment after 2 years, may be sooner if secondary infertility , with age as a possible factor
- Multifactorial: male, female, combination, unexplained
- Affects 88 million couples, 186 million individuals (WHO)
- Male infertility only recognised in the latter half of the C20
- 50-70% asymptomatic
What are the underlying causes of infertility in males and females?
- Incompatibility i.e. uterine pH.
- Antibodies to sperm (♀ or ♂).
- Medications.
- Knowledge and opportunity.
- Genetics: embryonic lethality.
What are the underlying causes of infertility in males?
- Sperm quality.
- Absence or blockage of ducts.
- Lack of gonadal tissue (Testes).
- Illness or Sexually Transmitted Diseases i.e. chlamydia.
- Sperm destruction.
- No sperm produced.
- Lack of ejaculation.
- Low testosterone
What are the underlying causes of infertility in females?
- Age (of oocyte).
- Problems with oocyte maturation and/or ovulation (oocyte or hormonal); common cause of fertility problems is polycystic ovary syndrome (PCOS).
- Lack of gonadal tissue (Ovaries).
- Lack of uterus or differences in uterine anatomy.
- Stage of uterine development (hormonal).
- Blockage of uterine tubes.
- Stress-physical and mental.
- Uterine scarring.
- Endometriosis and Pelvic Inflammatory Disease (PID).
- Cervical mucus.
- BMI.
SECONDARY INFERTILITY
Majority of people experiencing infertility have already had a
child: 1.9% females 20-44 experience primary infertility
versus 10.5% for secondary*
FERTILITY TREATMENT
REQUIREMENTS
• Donation/extraction of sperm
• Donation/extraction of oocytes
- Synchronisation of cycles
- Surrogate parent (where there are problems with uterus or giving birth)
FERTILITY TREATMENT CONSIDERATIONS
• Screening for infectious disease: sexually transmitted diseases, HIV, blood-borne viruses, hepatitis B and C, human T cell lymphotropic viruses (known to cause a type of cancer).
• Family history of Disease/genetic testing
- Pregnancy
- Hyperstimulation of ovaries
What is artificial insemination (AI or IUI)?
- Devised in 1790s by Dr John Hunter.
- Woman is inseminated with epididymal sperm.
- Treats idiopathic infertility, paraplegia, obstructed vas deferens, long separation or illness, same sex couples or single women and post-mortem.
- 15-30% success in cycles: dependent on sperm quality (morphology, motility, direction, speed).
- Cheaper than IVF, fewer procedures.
- Sperm improved with use of ‘swim-up’ technique: selecting for healthy sperm (swimming the right way etc).
- Sperm reaching the top layer are aspirated and washed for use.
What is intrauterine insemination (IUI)?
• Sperm placed high in the uterus, Bypasses 'hostile' mucous. • Overall, 60-70% success over 6 cycles. • Success per cycle was: 1) 15.8% for women under 35 2) 11.0% for women aged 35-39 3) 4.7% for women aged 40-42 4) 1.2% for women aged 43-44 5) 0% for women over 44 • Success depends on sperm count, quality. • Frozen sperm has no effect.
What is the history of infertility treatments?
- In Vitro Fertilisation was first used in the 1970s.
- Louise Joy Brown, conceived by IVF in Oldham General Hospital.
- Technology had been in development for 20 years+ Steptoe and Edwards.
- Sperm and eggs removed and fertilisation occurs outwith the body.
- Healthy embryo is implanted in the uterus.
- Offered to those who have not conceived after IUI.
IVF ELIGIBILITY
- 2 years of unsuccessful attempts to conceive
- Females must be <43
- had 12 unsuccessful rounds of IUI
- Where genetic testing is required
- Blocked uterine tubes
How are eggs retrieved, stored or donated for IVF?
• Hormonal treatment is given to suppress the natural (endogenous) cycle:
1) Gn RH agonists inhibit pituitary function.
2) GnRH antagonists inhibit LH/FSH release.
• Exogenous hormones stimulate/control ovulation:
1) Growth of oocytes occurs by Follicle Stimulating Hormone for 10-12 days or clomiphene citrate (not good with PCOS).
2) Maturation of oocytes occurs by artificial LH surge through human Chorionic Gonadotrophin (hCG).
3) Monitoring of oocytes is done by ultrasound and harvesting of oocytes (aspiration) completed transvaginally.
4) Hormones are given to prepare uterus (Progesterone) by injection or vaginally; pestrogen can also be given.
5) Aspiration from the ovary is followed by incubation with sperm for 12-16 hours
6) Evidence of a polar body is indicative of a healthy zygote; this can be collected for preimplantation genetic testing.
7) Viable zygotes cultured for several days (up to 6d), until a healthy blastocyst forms; there is transfer to uterus by a catheter; transplantation number is limited by the UK HEFA
Aspiration
involves assessment of the eggs via ultrasound then aspiration of the oocyte from the ovary;
this usually involves inflation of the abdomen to allow for manipulation and can be uncomfortable
the egg is incubated with sperm to allow fertilisation to occur
this is identified by evidence of pronuclei and polar body formation
testing is done on the polar body to prevent destruction of the zygote.
