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15 May 2003

Dear Colleague,

Guidance on Preimplantation Testing

In 1999 the HFEA and the then Advisory Committee on Genetic Testing (since incorporated into the Human Genetic Commission, HGC) held a public consultation on the clinical use of preimplantation genetic diagnosis (PGD).

During 2001 a HFEA / HGC Joint Working Party was established to take forward the consultation exercise and to produce recommendations for the revision of the PGD guidance. Following this process the HFEA has established new guidance on preimplantation testing. This guidance, which replaces the interim guidance on PGD issued in 1999, is enclosed with this letter (attached at Annex A).

The revised guidance is designed as an integrated guidance to cover all forms of preimplantation testing that is: all testing of embryos in vitro, material removed from embryos and the gametes that produced them, prior to embryos transfer.

Preimplantation testing is a relative new treatment service and to ensure patient safety the HFEA will continue to monitor this procedure carefully through its regulatory processes. To support effective regulation and monitoring of the use of preimplantation testing, the HFEA is issuing Directions requiring centres to record and report detailed information in relation to practitioners carrying out polar body/blastomere biopsies and each treatment cycle involving either preimplantation genetic diagnosis of embryos or preimplantation genetic screening of embryos.

If you have any requires about this letter please contact the Directorate of Regulation on 020 7375 3017.

Yours faithfully,

Suzi Leather
Chair

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Annex A

HFEA Guidance on Preimplantation Genetic Testing

PREIMPLANTATION TESTING

GENERAL

Definitions
Preimplantation genetic diagnosis (PGD) is a technique which involves the genetic testing of embryos created in vitro for deleterious, heritable genetic conditions which are known to be present in the family of those seeking treatment and from which the embryos are known to be at risk.  The technique typically involves several stages: the creation of an embryo in vitro, the removal of one or more blastomeres, the genetic testing of those blastomeres for certain genetic conditions and the transfer of suitable embryos to a woman. The purpose of PGD is to provide information that allows unaffected embryos to be selected for transfer.  People seeking PGD may have different requirements from those requiring IVF to overcome fertility problems since they are not necessarily infertile.

Preimplantation genetic screening (PGS or aneuploidy screening) is to be distinguished from preimplantation genetic diagnosis in which a pre-existing diagnosis indicates that an embryo is at significant risk of being affected by a serious genetic condition.  PGS refers to techniques whereby certain categories of patient thought to be at a higher than average risk of conceiving chromosomally abnormal embryos have their embryos tested (by blastomere or polar body biopsy) to determine whether certain abnormalities are present.

The purpose of preimplantation screening for aneuploidy is to help those seeking assisted conception treatment for their infertility to achieve a successful pregnancy and to reduce their risk of miscarriage. Whilst it helps to identify chromosomally abnormal embryos, aneuploidy screening (PGS) does not necessarily identify normal embryos. In some cases, information discovered through preimplantation testing may help those who have been unable to conceive or carry children identify the underlying basis of their infertility.

POLAR BODY/BLASTOMERE BIOPSY

A polar body/blastomere biopsy practitioner is defined as the person who removes polar bodies or cells from the egg or embryo for the purpose of preimplantation genetic diagnosis (PGD) or preimplantation genetic screening (PGS).

Polar body/blastomere biopsy may only be carried out by trained, competent staff recognised as such by the HFEA.

LICENSING OF PREIMPLANTATION TESTING

Centres may only carry out preimplantation tests for those genetic conditions, chromosomes or traits (or combinations of these), and using those specific tests (or combinations of tests), listed in the preimplantation testing Annex to their licence or approved by a licence committee in any particular case.

Centres must submit an application to the HFEA for each new condition for which they wish to test and for each new test that they wish to use (the HFEA produces separate detailed guidance on submitting new preimplantation testing applications).

Centres wishing to test a single embryo for more than one genetic condition or trait must apply to the HFEA for each specific combination of tests that they propose to use, irrespective of whether the centre is already licensed to use each of the tests individually.

Embryos from which biopsies have been taken, or resulting from gametes from which biopsies have been taken, may not be transferred with any other (non-biopsied) embryos in the same treatment cycle.

Centres may not use any information derived from tests on an embryo, or any material removed from it or from the gametes that produced it, to select embryos of a particular sex for non-medical reasons.

ACCREDITATION OF GENETICS LABORATORIES

All genetics laboratories used for preimplantation testing are expected to be CPA accredited (or equivalent) or at least be working towards Clinical Pathology Accreditation, with accreditation to be completed within five years.

PREIMPLANTATION GENETIC DIAGNOSIS

Staff involved

It is expected that a multidisciplinary team will be involved in the provision of the PGD service, including reproductive specialists, embryologists, clinical geneticists, genetic counsellors, cytogeneticists and molecular geneticists. This team is expected to maintain close contact with the primary care physician or the referring clinician, and treatment is expected to also encompass continued support of patients following PGD.

Genetic Consultation

People seeking treatment are expected to have access to both clinical geneticists and genetic counsellors.

Ideally, people seeking treatment are expected to be have been seen in and thus referred to the treating centre by a Regional Genetics Centre. If not, all those seeking treatment are expected to at least be known to an accredited clinical geneticist.

Centres are expected to work closely with the local genetics team of those seeking treatment.

Patient information

The patient information for PGD is expected to include reference to the process, procedures and risks involved in undertaking IVF and biopsy procedures in the context of the provision of a sophisticated genetic test.  Reference is expected to be made to the experience of the clinic in carrying out the procedure.

Information provided to those seeking treatment to be taken into account is expected to include:

(i)  Genetic and clinical information about the specific condition

(ii)  Its likely impact on those affected and their families

(iii)  Information about treatment and social support available

(iv)  Where the family has no direct experience of the condition, the testimony of families and individuals about the full range of their experiences of living with the condition

Where information about the particular genetic disorder has already been provided, for example by a regional genetics centre, it will not be necessary to provide this information again.  If this is the case, the treating centre is expected to satisfy itself that this information has already been provided to a satisfactory standard.

The possible outcomes of genetic testing and their implications are expected to have been fully explored with those seeking treatment prior to PGD being undertaken.

Clinical decision-making

The decision to use PGD is expected to be made in consideration of the unique circumstances of those seeking treatment, rather than the fact that they carry a particular genetic condition.

Indications for the use of PGD are expected to be consistent with current practice in the use of (post-implantation) prenatal diagnosis (PND).

It is expected that PGD will be available only where there is a significant risk of a serious genetic condition being present in the embryo. The perception of the level of risk by those seeking treatment is an important factor in the decision-making process. The seriousness of the condition is expected to be a matter for discussion between the people seeking treatment and the clinical team.

In any particular situation the following factors are expected to be considered when deciding the appropriateness of PGD:

(i)  The view of the  people seeking treatment of the condition

(ii)  Their previous reproductive experience

(iii)  The likely degree of suffering associated with the condition

(iv)  The availability of effective therapy, now and in the future

(v)  The speed of degeneration in progressive disorders

(vi)  The extent of any intellectual impairment

(vii)  The extent of social support available

(viii)  The family circumstances of the people seeking treatment

PREIMPLANTATION GENETIC SCREENING FOR ANEUPLOIDY

Preimplantation genetic screening (PGS) for abnormal number of chromosomes (aneuploidy screening) may be performed either on blastomeres removed from cleavage stage embryos or on first and second polar bodies removed from eggs/embryos during in vitro fertilisation.

It is expected that PGS for aneuploidy will only to be used in the treatment of the following categories of patient:

(i)  Women over 35 years of age

(ii)  Women with a history of recurrent miscarriage not caused by translocations or other chromosomal rearrangements Perhaps you wish to insert ? "the latter are covered by PGD regulations"

(iii)  Women with several previous failed IVF attempts where embryos have been transferred

(iv)  Women with a family history of aneuploidy not caused by translocations or other chromosomal rearrangements

Patient information

Patient information for PGS for aneuploidy is expected to include reference to the process, procedures and risks involved in undertaking IVF and biopsy procedures. Reference is expected to be made to the experience of the clinic in carrying out the procedure.  Patients are expected to be also informed in writing:

(i)  That embryos that have been biopsied may not be suitable for cryopreservation and use in subsequent treatment cycles

(ii)  That the more tests that are used to examine the chromosomes, the greater the likelihood of finding chromosome abnormalities (whether they are biologically significant or not), and thus the lower the chance of finding suitable embryos for transfer

(iii)  Of the procedure to be followed in the case of a diagnostic failure or uncertainty

(iv)  That there is no guarantee against a miscarriage occurring despite preimplantation aneuploidy screening being performed

(v)  That patients are recommended to undergo prenatal screening

(vi)  Of the financial costs of treatment

(vii)  Of the emotional burden expected if a successful pregnancy not result following PGS for aneuploidy

Centres are expected to inform patients that genetic counselling is available and are expected to make arrangements to provide such counselling if required.

Annex B

RECORDING AND REPORTING OF INFORMATION

The Person Responsible at a centre must notify the Authority in writing before clinical polar body/blastomere biopsy procedures are first carried out by a particular practitioner at that centre. (see General Direction D.2003/1).

Twelve months after a polar body/blastomere biopsy practitioner has been recognised as competent, the Person Responsible must provide the Authority with the information set out in the appropriate Schedule to General Directions D. 2003/1.

Where information submitted to the HFEA indicates a significant break in the proposed practitioner's practice of polar body/blastomere biopsy, the Authority may require re-examination of the person's competence in the relevant technique.

For each treatment cycle involving preimplantation testing the Person Responsible must record the information set out in the appropriate Schedule to General Direction D. 2003/1.

Page last updated: 14 April 2009

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