Pregnancy Options

Preimplantation Genetic Diagnosis

Dr Georgios Christopoulos MRCOG MD PGDip

Subspecialty Registrar in Reproductive Medicine

IVF Hammersmith

Imperial College Healthcare NHS Trust

Overview

Introduction to genetic diagnosis

How is it done?

Current Status

Provision on the NHS

Ethical Challenges

Take Home Messages

Reproductive RouletteChoices available to people who are genetic carriers

• Remain childless

• Adoption

• Natural pregnancy and accept risk of “reproductive roulette”

• Prenatal diagnosis

• -invasive (amniocentesis, chorionic villus sampling)

-cell free fetal DNA

• gamete donation (OD)

• PGD

Amniocentesis

• Performed after 15

weeks’ gestation

• Local anaesthetic

• Usually after routine

antenatal screening at

12 weeks’ gestation

• 1% risk of miscarriage(Tabor et al, Lancet 1986)

Chorionic Villous Sampling

(CVS)

• Performed at 11-13

weeks’ gestation

• Local anaesthetic

• Allows earlier detection

than amniocentesis

• Similar pregnancy loss

rates as amniocentesis

Non Invasive Prenatal Testing (NIPT)

As early as 7 weeks’ gestation

Presence of Y chromosome

1%-4% no results

Not part of routine NHS screening

What is an IVF cycle?

Day 1 2 3 4 5 6 7 8 9 10 11 12

GnRH antagonist when

follicle >14mm

Recombinant FSH daily

Egg retrieval

Preimplantation genetic diagnosis

ALD and PGD

• First successful PGD

was performed for an

ALD carrier (Handyside et al. 1990)

• Embryo sexing (FISH)

• Direct mutation testing

Current Status

• HFEA PGD List-http://www.hfea.gov.uk/cps/hfea/

gen/pgd-screening.htm

• ‘Have your say’…..

• 22 UK clinics on HFEA list,

PGD is 0.4% of UK ART

cycles

New Service Developments

• New funding for NHS PGD in England April

2013 for equality, consistency and clarity

• http://www.england.nhs.uk/wp-

content/uploads/2013/04/e01-p-a.pdf

• 3 cycles funded on the NHS

• No living unaffected child from the

relationship

• Valid HFEA license for clinic and disease,

CPA for laboratory

Ethical considerations

• Disposal of all healthy male embryos with

embryo sexing

• Transfer of female carrier embryo

• Allowing choice of sex

(unaffected male vs. carrier female embryo)

• Morphology and quality of embryos as guide

Take-home Messages

• Increasing safety, accuracy, pregnancy rates,

access and acceptance

• Diagnose ALD status prior to implantation

• Maintain realistic perspective: low success of

treatment, complex nature of disease