Sex Selection Outline

Sex Selection
Dr Devora Lieberman MD MPH FRANZCOG
Outline
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History of sex selection
Some more “modern” ideas
Assisted conception techniques
Demographic issues
Ethical issues
Sex selection in Australia pre- and post-2004
Aristotle, 330 BC
For a boy, ligate
your left
testicle
13th century Chinese Conception Chart
French Noblemen
Cut a testicle off to conceive a boy
“Drink the blood of a lion by a full
moon in a cold wind with a woman
dressed in a man’s clothing…”
The 21st Century
• Surveys of the general population favour
regulating sex selection
– HFEA found 68% of 2,165 adults in favour in faceto-face survey1
– 82% in favour of 642 respondents to selfadministered survey1
– Germany- 92% not interested in sex selection2
1
www.hfea.gov.uk/AboutHFEA/Consultations
et al. Hum Reprod 2003
2 Dahl
Ask Dr Google
• “conceive a girl”- 1,970,000 results
• “conceive a boy”- 1,710,000 results
• 750,000 on-line forums
Shettles Method
• Based on concept that the y chromosome is
lighter than the X chromosome
• Y-bearing sperm swim faster and die sooner
than X-bearing sperm
• For a girl, time intercourse in advance of
ovulation
• For a boy, time intercourse at ovulation
• Sexual position, diet, pH
Gender Disappointment
Assisted Conception Techniques
• Sperm separation
• Preimplantation genetic diagnosis (PGD)
Sex Selection Among Infertility
Patients1
• Cross-sectional survey of 1,500 women who
presented for infertility care (1,385 reached
correct address
• 561 completed questionnaires (41% response
rate)
• 40.8% wanted to choose the sex pf their next
child if there was no added cost
1 Jain
et al. Fert & Ster 2005
Sex Selection Among Infertility
Patients
• A significant preference in women who were:
– Younger
– Single
– African American
– Hispanic/Latina
– Less educated
– Nonreligious
– Less wealthy
– Had never been pregnant
– Had children of one sex
Sperm Selection
(Microsort®)
• Uses a flow cytometer that separates the 2.8%
heavier sperm sample for artificial
insemination or IVF
• Efficacy*:
– 80-90% for X-bearing sperm
– 60-70% for Y-bearing sperm
*Johnson et al. Hum Reprod 1993
What is PGD ?
Uses a test, or group of tests to identify
the embryo’s genetic/chromosomal
status
Why use PGD?
• Avoidance of therapeutic abortion or spontaneous
miscarriage for couples at high risk of fetal
abnormality
• Avoidance of moral/ethical dilemmas about
termination of pregnancy
• Refinements of techniques allow us to offer patients
a 95-99% rate of successful analysis giving patients a
greater degree of confidence as they approach a prenatal diagnostic test.
What can PGD test for?
• Translocations
• Aneuploidy screening
• Single gene disorders
– autosomal dominant eg. Huntington disease
– autosomal recessive eg. Cystic Fibrosis
– X-linked eg. Haemophilia
• HLA matching
• Sex selection
How is PGD done?
1. Removal of genetic material – either day 3 biopsy
or day 5 biopsy
2. Analysis of the biopsied material – CGH or PCR
3. Interpretation of results
4. Selection of embryos for transfer
ICSI
Embryo Development
Blastocyst Biopsy
Blastocyst Biopsy
DNA is extracted from the cells ...
PCR: DNA is amplified to get usable
quantity
PCR based PGD: developed to date
A.R. polycystic kidney disease
Adrenoleukodystrophy
Alpers disease
alpha 1 anti Trypsin
alpha thalassaemia
anti-kell antibodies
ARPKD. PKHD Gene
Batten disease
Becker Muscular Dystrophy.
beta thalassemia
CADASIL disease
CDG 1A
central core disease
Charcot-Marie-Tooth
choroideremiachronic granulomatosis disease
congenital adrenal hyperplasia
congenital nephrotic syndrome
Connexin 26
Crigler-Naijar syndrom(+SSM)
Crouzon Syndrome
cystic fibrosis
D-Loop
Duchenne muscular dystrophy
early onset Alzheimer's disease
Kell Antibody
Zellweger syndrome
X-linked myotubuar myopathy
X-linked Lowe oculocerebrorenal syndrome
X-linked adrenoleukodystrophy
Von Hippel-Lindau
medium-chain acyl-CoA dehydrogenase deficiency
E-cadherin
Medullary Thyroid Cancer RET
ectodermal dysplasia
MELAS
Emery-Dreifuss
Metachromatic Leucodystrophy
muscular dystrophy
Mitochondrial diorders
facioscapulohumeral muscular
MPS II Hunter
dystrophy
MTHFR FV
familial adenomatous polyposis
mucopolysaccharide III
familial amytrophic lateral sclerosis
multiple endocrine neoplasia 2A
family history of deafness
multiple hereditary exotoses (EXT1)
fragile X
muscular dystrophy
FSH MD
nail-patella syndrome
Goldberg-Shprintzen syndrome
nemaline myopathy
Gorlin Syndrome
neurofibromatosis type 2
granulomatosis disease
Treacher Collins
Haemophilia
Norrie disease
Helitz Epidermolysis Bullosa
OCRL on Chromosome X
HLA Match
oculocutaneous albinism 2
HLA Match for Diamond Blackfan
Parental (3PN Inv)
Anaemia
Pendred syndrome
HLA match/ hyper IgM
Pericentric Inversion on X chromosome
HLA matching, Aplastic anaemia
POC - Turners Mosaicism;partial del Chromosome X
HLA matching, Juvenile
proximal myotonic myopathy
Myelomonocytic Leukemia
Retinoblastoma
HLA matching, Leukaemia
rhesus determination
Huntingdon disease
Saethre-Chotzen Syndrome
Hypochondroplasia
Sandhoff disease
incontinentia pigmenti
sickle cell anaemia
juvenile neuronal ceroid lipofuscinosis
spinal muscular atrophy
Wolman disease
thyroid cancer
Wiskott-Aldrich syndrome
tuberous sclerosis
Ullrich congenital muscular dystrophy
Hybridisation
Challenges
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Ovaries must respond to stimulation
Mature eggs must be collected
Eggs must fertilise
Embryos must be suitable for biopsy
Embryo of desired sex
Demographic and Ethical Issues
Demographic Issues
• China and India
• India has outlawed sex selection
• Sex ratio for newborns in China- 118:100, and
as high as 130:100 in rural areas
• 2003 US Gallup Poll of 1,003 adults:1
– 35% boy
– 28% girl
– 34% no preference
1
Lyons. The Gallup Organization 2003.
Sydney IVF Experience
• 286 cycles completed between 1996 and June
2004
• Compulsory counselling introduced in 2001
for all PGD patients, including those
requesting sex selection
• Questionnaire introduced April 2002
– 164 surveys completed in 2 years
• Medicare has never subsidised this elective
treatment.
Parent’s main reason for sex
selection
11%
13%
7%
69%
Mother
Father
Ethical Issues
• In 2004 the Australian Health Ethics
Committee stated that it found the practice of
sex selection to be unethical
• On 9 February 2005 Sydney IVF suspended sex
selection for non-medical reasons to comply
with AHEC Guidelines
AHEC’s reasons given for opposing the
availability of sex selection
• Sex selection is incompatible with the parent–child
relationship being one that involves unconditional
acceptance.
• Sex selection may be an expression of sexual
prejudice, in particular against girls. As practised
today around the world, it generally reflects and
contributes to bias and discrimination against
women.
• Sex selection harms men in some cultural groups (by
contributing to the shortage of women for men to
marry).
AHEC’s reasons given in support of the
availability of sex selection
• Sex selection permits ‘family balancing’.
• Sex selection may enable parents to fulfill
religious obligations or cultural expectations.
• Sex selection is properly thought of as a
matter for individual autonomy.
Sydney IVF’s Ethics Committee
• “Sex selection is incompatible with the
parent-child relationship being one that
involves unconditional acceptance.”
“Unconditional acceptance” is an abstract and
arguable concept at best – and completely
meaningless for a child still to be conceived.
Sydney IVF’s Ethics Committee
• “Sex selection may be an expression of sexual prejudice, in
particular against girls. As practised today around the
world, it generally reflects and contributes to bias and
discrimination against women.” AND
“Sex selection harms men in some cultural groups (by
contributing to the shortage of women for men to marry).”
These observations may be true in China and India but do not
apply in Australia. In our experience the object of sex
selection in just under 60% of cases was to have a girl.
Conclusion
• The desire to influence the sex of one’s
children is ancient and deep-seated.
• Couples turn to many methods, with more or
less cost and effectiveness.
• IVF with PGD is the latest and most effective
of these, and removes the element of chance.