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HRANICE ŽIVOTA
ASISTOVANÁ REPRODUKCIA
Prof. RNDr. Michal Zeman, DrSc.
PriF UK, Bioetika
Hranice života
Počatie – Narodenie –
Dospievanie- Reprodukcia-
Postreprodukčný vek- Staroba-
Smrť
Fertilita– poznanie fyziológie reprodukcie
– poznanie antikoncepčných metód
– informované rozhodnutie o počatí
– plánované rodičovstvo
v škole a rodine mnohé tabu
BIOETIKA – zdôrazňuje právo človeka na
dostatočné kvalitné vzdelanie v súlade
s najnovšími poznatkami vedy
Nezávislosť sexuálneho styku od
reprodukcie u ľudí
- sexuálna receptívnosť počas celého cyklu
- sex - upevňovanie dlhodobých
párových vzťahov
- pro-kreačný sex sa stáva re-kreačným
Evolučné aspekty
- výhody a nevýhody „tabu“
- nedotknuteľnosť manželstva
nevera
- výrazný pokles reprodukčného fitness v
modernej industriálnej spoločnosti
Fyziológia reprodukcie
Semenníky a spermiogenéza
Nedeterminovaná mitotická aktivita spermiogónii
Hormonálna regulácia u samcov
▪ U ľudí - 250 000 oocytov, ale iba 400-500
ovuluje za život
estrogénov
▪ Folikuly – produkcia androgénov
gestagénov ➭
progesterón (neskôr corpus luteum)
▪ Folikulárny rast a diferenciácia je indukovaný
FSH a stimulačný IFG-I
Samičí reprodukčný systém
Oogenéza
Oogónie stratili mitotickú aktivitu
Menštruačný cyklus
hypofýza
ovárium
steroidy
uterus
Antikoncepčné metódy
• Koncepcia neplodných dní
• Fyzikálne metódy
• Hormonálne
Antikoncepcia – stará otázka
Čínska medicína – indukcie potratov
2 700 p.n.l.
Starý EgyptKahun papyrus – 1 850 p.n.l.
vaginálne pasty,
menzes indukujúce pasty
sexuálna abstinencia v určitých fázach cyklu
1500 p.n.l. - spermicídne účinky guličiek z
gumovníka s kyslým pH
Prirodzená kontrola reprodukcie- vajíčko schopné oplodnenia 24-36 h po ovulácii
- spermie môžu prežívať 48-56 hod. v reprod. trakte
ženy
- zlyhanie 2-24% v 1 roku
Rozvojový svet, nielen– prirodzené - lacné
– žiadne vedľajšie, negatívne dôsledky
Antikoncepcia – problém
Politický - Stanovisko štátu
Čína,
Arabské krajiny
NaboženskýKatolícke – encyklika Humanae Vitae
Islam
Hormonálna antikoncepcia
➢ výhody
➢ nevýhody
➢ akcepovateľnosť
➢ spoločnosťou (islam, kresťanstvo)
➢ samotnou ženou
Asistovaná reprodukcia15% infertilných párov
Pokles počtu spermií na polovicu u mužov za
posledných 50 rokov
113.106 ml – 1940
66.106 ml – 1990
Normospermia – WHO definícia (2010)Objem ejakulátu: 1,5 ml
Koncentrácia spermií: 15 miliónov/ml a viac
Celkový počet spermií v ejakuláte: 39 miliónov a viac
Celková pohyblivosť: 40 % a viac pohyblivých spermií
Progresivý pohyb: 32 % a viac
Morfológia: viac ako 4 % s normálnou stavbou
Vitalita: 58 % živých spermií
Leukocyty: menej ako 1 milión/ml
MEDICAL INFERTILITY
Affects 10-15% of couples attempting pregnancy
DISTRIBUTION OF CAUSE
FEMALE INFERTILITY
(from Ian Pike’s
guest lecture)
LIFESTYLE AND FERTILITY
OVERALL FITNESS AND THE CAPABILITY
TO BEAR HEALTHY CHILDREN DEPENDS ON:
1. OUR GENES
2. THE CONDITIONS UNDER WHICH WE LIVE
3. THE WAYS IN WHICH WE BEHAVE
INFERTILITY – THE INABILITY TO ACHIEVE PREGNANCY
1. MEDICALa) After 12 months of unprotected sexual intercourse or
b) Due to a diagnosed physical abnormality of the
reproductive system; e.g., blocked fallopian tubes
2. SOCIALNon-engagement in a heterosexual relationship
3. THE INABILITY TO CARRY A PREGNANCY TO LIVE BIRTH
MALE INFERTILITY
FERTILITY DECLINES WITH AGE
Female infertility increases from
30 years of age to the menopause
Genetic anomalies in men also increases with age
(from Ian Pike’s
guest lecture)
MANY CONCEPTUSES DO NOT SURVIVE
Human fecundity rate; i.e., the probability of achieving a clinical recognized
pregnancy within any given menstrual cycle, is about 25% and high levels of
fertilization failures or early developmental death, are the norm at conception
Spontaneous abortion is one of Nature’s ways to counter negative genetic and
environmental factors
MAXIMIZING FERTILITY AND REPRODUCTIVE OUTCOME:
GENERAL HEALTH ISSUES
THERE ARE SEVERAL THINGS POTENTIAL PARENTS CAN DO TO
SIGNIFICANTLY IMPROVE THEIR REPRODUCTIVE HEALTH AND REDUCE
THE CHANCE FOR ASSISTED REPRODUCTIVE TECHNOLOGY TREATMENT
i) NUTRITION AND REPRODUCTION
All essential nutrients in diet - women who are
significantly overweight or underweight can
have difficulty getting pregnant
ii) EXERCISE AND REPRODUCTION
Regular aerobic exercises but excessive can affect
ovulation and sperm count
iii) SUBSTANCE ABUSE AND REPRODUCTION
Alcohol, nicotine, illicit drugs and some medications
adversely affect the embryo, fetus and newborn
iv) FOLIC ACID AND NEURAL TUBE DEFECTS
Is recommended as daily food supplement
prior to conceptionBeans and green leafy vegetables are a rich source of
folic acid (from E. Hyams ‘Plants in the Service of Man’.
Dent & Sons, 1971)
MAXIMIZING FERTILITY AND REPRODUCTIVE OUTCOME:
GENERAL HEALTH ISSUES CONTINUED
v) TEMPERATURE EFFECTS AND SPERM QUALITY
Optimum spermatogenesis 4-7˚ C below body temperature
vi) PHYSICAL AND PSYCHOLOGICAL STRESS
A relationship between emotion and fertility exists
vii) REGULARITY OF INTERCOURSE
2-3 times per week, particularly around the time of ovulation
viii) SCREENING TESTS
Both partners have blood
tests taken for HIV
antibodies, hepatitis B&C,
and females for immunity to
Rubella (German Measles) –
the virus known to cause
major abnormalities in the
fetus if contracted during
early pregnancy
‘The Stairs of Age’ by Winter Carl
Hansson (1777-1805)
PART II : ASSISTED REPRODUCTIVE TECHNOLOGY (ART)
Since the first ‘test-tube’ baby Louise Brown was born in Britain in 1978,
several millions of children have been born through assisted reproduction
Social Impacts of Assisted Reproductive Technology
Donor insemination is more successful than partner insemination,
does not carry an increased risk of spontaneous abortion or
congenital anomalies, and has advantages over adoption in that the
child is genetically related to the mother and the couple can
experience conception, pregnancy and delivery
ARTIFICIAL INSEMINATION BY HUSBAND OR BY DONOR
INTRACYTOPLASMIC SPERM INJECTION (ICSI)
ICSI, in conjunction with IVF technology, has given
hope to men with sever infertility problems
Even immature spermatids (sperm precursor cells)
can be harvested and used to fertilize the egg
FEMALE-FACTOR INFERTILITY: IN VITRO FERTILIZATION (IVF) TECHNOLOGY
AIM OF TREATMENT
1. Menstrual Cycle Management
2. Control Ovaries by Drugs
a) Drug 1 – block usual control mechanism
from brain X ovary
b) Drug 2 – Direct stimulation to the ovary
c) Develop a batch of eggs
IN VITRO FERTILIZATION (IVF) TECHNOLOGY CONTINUED
3. Prepare Eggs for Fertilization
4. Drug 3 – induce ovulation
5. Harvest eggs
6. In vitro fertilization
PROTOCOL - IVF TREATMENT CYCLE
Key
U/S Ultrasound Scan
* FSH daily injections
Blood hormone test
(E = estradiol 17β)
a GnRH analogue – daily
injection(from N.S. Fertility)
TECHNOLOGIES IN COMBINATION WITH IVF TECHNOLOGY
PREIMPLANTATION GENETIC DIAGNOSIS (PGD)
Alternative to ultrasound, amniocentesis or chorionic villus sampling
STORAGE FOR FROZEN EMBRYO TRANSFER
SPERM, EGG AND EMBRYO DONATION
1. Female Infertility
Premature Menopause
Genetic Disease Carrier Donor Egg
Age Factor & Chronic IVF Failure
Lack of / Unsuitable Uterus Surrogacy
2. Male Infertility
Abnormal Semen Donor Sperm
3. Couple Infertility
Chronic IVF Failure Donor Embryo
Bioetické limitácieVeľká Británia – zákon o asistovanej reprodukcii
Žene sa nemá poskytovať reprodukčná
asistencia, kým sa nezabezpečí welfare
dieťaťa, ktoré sa má narodiť v dôsledku
ošetrenia (vrátane otca dieťaťa)
a akéhokoľvek iného dieťaťa, ktoré môže
byť poškodené zákrokom
Identifikácia donorov gamiet – ÁNO/NIE?
Švédsko 1985 –
Dnes
donori musia byť registrovaní
Povedať- Nepovedať dieťaťu o jeho
počatí
Dnes - väčšina manželov
– ANO o pôvode dieťaťa
SEX SELECTION AND DESIGNER CHILDREN
ASSISTED REPRODUCTION : RISKS AND UNCERTAINTIES
Some researchers are questioning the safety of technologies such as ICSI
and other invasive techniques, claiming that they may be linked to increased
rates of birth defects and rare genetic imprinting disorders
Dolly the sheep – the world’s first cloned mammal was euthanized 14th February, 2003
(The Japan Times, February 16, 2003)
TECHNOLOGIES IN COMBINATION WITH IVF TECHNOLOGY CONTINUED
ĎAKUJEM
Research into cell and tissue
differentiation using cultured
embryonic stem cells from
humans, and other species,
may enable the control of
differentiation and
dedifferentiation in somatic
cells. This could allow the
production of tissues with
enhanced stem cell
components that may be
used as universal donor cells
for transplantation
(To-day’s Life Sciences, March/April 1999)
BALANCING RISKS AND
UNCERTAINTIES