30 April 2019
Recent media coverage has highlighted claims by a senior Harvard professor of genetics that people should undergo genetic testing before starting a family. There are understood to be around 7,000 inherited conditions and five percent of babies are born with one of these. He says controversially, these inherited conditions could be avoided if people underwent pre-implantation genetic testing to screen embryos or underwent pre-natal testing and termination, saving millions of pounds for health providers like the NHS.
However, a decision about whether to undertake genetic testing is a big step. There is a lot to consider and it brings with it a range of challenging medical, legal and wider issues and implications. Furthermore, whilst there are more options for genetic testing than ever before, including individual diagnostic testing, pre-implantation embryo testing, pre-natal and post-birth testing, they do not guarantee a healthy child or a positive family life.
Individual Genetic Testing
Individuals from certain ethnic and religious communities, as well as those with a family background of a genetic disorder, may seek to undertake diagnostic and carrier testing to try to minimise the risk of passing on an inherited disease. If they are found to be a carrier, they may then choose to undergo fertility treatment and further genetic testing options.
For example, individuals with family members who carry the BRCA1 and BRCA2 mutations (linked to breast and ovarian cancer) may want to undergo genetic testing to help preserve their own health as well as gain a better understanding of whether they are likely to pass the defective gene on to their child. Some Jewish communities also have a much higher risk of passing on a genetic disorder like Tay-Sachs disease and have for the last few years actively encouraged genetic testing. However, diagnostic and carrier testing is not available for all genes or genetic conditions and it can be a daunting exercise.
Pre-implantation Genetic Screening (PGS)
Individuals can be a carrier of a chromosome abnormality without experiencing any symptoms. Chromosome abnormalities are responsible for conditions like Down’s Syndrome and Edward’s Syndrome (a severe genetic disorder which is often fatal before or shortly after birth). Chromosome abnormalities are also believed to be the most common cause of miscarriages. Women and couples have therefore traditionally been invited to consider PGS if they are at risk of passing on a chromosome abnormality (too few or too many chromosomes) to their child, as well as:
- Couples who have had a previous pregnancy with a chromosomal abnormality.
- Women who have had recurrent miscarriages (two or more).
- Women who have experienced previous failed embryo implantation.
- Women diagnosed with unexplained infertility.
- Women aged over 37.
- Women who have undergone numerous unsuccessful fertility treatment.
In the past, early research results looked promising. They suggested that undertaking PGS and only transferring embryos that are chromosomally normal could increase IVF success rates by as much as 23 percent for women and couples who had experienced recurrent miscarriages or failed IVF cycles and women older than 37 using their own eggs. However, more recent research shows there is little evidence that PGS improves the chances of a successful pregnancy for these groups of people. That said, some recent small clinical trials suggest that PGS may improve IVF success rates for women under 37 with no history of miscarriage or failed IVF cycles.
Pre-implantation Genetic Diagnosis (PGD) and Pre-implantation Tissue Typing (PTT)
Unlike PGS which screens for a chromosomal abnormality, pre-implantation genetic diagnosis (PGD) currently screens for around 400 genetic conditions. A family background of genetic disorders can increase the chances a child will be born with a genetic disorder. PGD tests for a range of genetic disorders that one (or both parents) is known or suspected to carry including: Huntington’s Disease, Sickle Cell Anaemia, Muscular Dystrophy, Cystic Fibrosis, Fragile-X Syndrome and Tay-Sachs disease. However, whilst PGD can help reduce the risk of passing on a genetic disorder, it does not eliminate the risk and in some cases pre-natal testing is also needed.
PGD is used in some jurisdictions for gender selection. However, in the UK gender selection is only allowed for certain medical reasons and sex selection for social reasons is not permitted.
Pre-implantation tissue typing (PTT) can be used to help identify and implant an embryo that is an exact tissue match to a sibling with a serious and life-limiting condition (various blood disorders). The technique can bring about a child, known as a ‘saviour sibling’, who can then become a donor (using their stem cells) to help treat the life-limiting condition. However, PTT is carefully considered on a case-by-case basis in the UK and it remains a rapidly evolving area.
Process: PGS and PGD
In cases involving PGS and PGD, a small number of cells are removed from day 3 or day 5 embryos (an embryo biopsy) in the IVF laboratory and sent for testing. The embryos are then frozen pending the results, which can take 7-10 days following the biopsy. It is generally advised that the greater the number of embryos, the better the chances one or more of the embryos will have a normal chromosome count and be suitable for embryo transfer. However, PGS and PGD do no guarantee a successful pregnancy and healthy child. They can also create challenging issues for patients about the number of fertility treatment cycles to undergo and what should happen to their remaining unused embryos.
Pre-natal testing can help screen for genetic conditions, but they are not always accurate. They can involve blood tests and ultrasound scans to test for conditions like Down’s Syndrome or Edward’s Syndrome and physical abnormalities. The test results can also make for difficult decisions for parents about whether to continue the pregnancy or undergo further treatment.
The wider picture
Through my specialist legal practice over the last ten to twenty years, I have seen many people struggle to have a family in the face of serious health issues, unexplained infertility, unsuccessful fertility treatment, recurrent miscarriages, diminishing fertility levels and unexpected changes and disappointment in their personal lives and relationships. Whilst fertility treatment and genetic testing can help people achieve a much-wanted family, it is only part of the picture.
Family building and fertility treatment can be emotionally demanding and stressful and it can strain relationships. People can generally only set aside a certain amount of time, energy and financial resources for family building and treatment. The process can feel overwhelming at times and it is sadly all too easy to overlook the complex fertility and family law aspects. Personal circumstances, feelings and wishes can also change over time. This can lead to a change of heart and sometimes relationship breakdown during fertility treatment or after the birth of a child. This can create complex legal issues about family building and the legal status, identity and rights of parents, children and families formed through assisted reproduction.
The value of specialist fertility and family law advice
Specialist fertility and family law advice can provide legal and practical advice and assistance which helps prospective parents and fertility patients navigate genetic testing issues, fertility treatment and family building outcomes. It can:
- create a bespoke family building legal and practical action plan which can help navigate the fertility sector, help preserve and maximise individual fertility, help individuals understand and make better informed decisions about conception, family creation, their biological identity and legacy and legal outcomes if life does not go to plan.
- provide informed legal (as opposed to medical) consent to fertility treatment and genetic testing at a UK fertility clinic, including: procurement, storage and use of gametes and embryos in treatment, posthumous conception and legal issues and outcomes if circumstances change or difficulties arise in practice.
- advise on alternative family building options and legal issues if genetic testing advises against conception with an individual’s own eggs, sperm or embryos or fertility treatment is unsuccessful.
- create a bespoke and viable legal action plan in complex situations e.g. request for pre-implantation tissue typing (PTT) in situations where the condition is not on the UK’s approved PTT List.
Need an expert fertility lawyer? If you would like to discuss your situation or you require specialist fertility and family law advice and assistance please contact Louisa Ghevaert by email email@example.com or by telephone +44 (0)20 7965 8399.