What are IVF and PGD?
In Vitro Fertilisation is a fertility treatment with the aim of having a woman end up pregnant with a viable embryo. PGD can be carried out within the IVF process at the point identified below. PGD is an assisted reproductive technology (ART), the purpose of which is to ensure the embryo chosen is free of a specific genetic condition it is tested for. PGD can be used to test for genetic conditions such mutations in the BRCA gene, or the cystic fibrosis genes.*
STEPS OF IVF**
STEP ONE – Ovulation induction
Ovaries are examined to check eggs are being produced (through a transvaginal ultrasound). Hormones are checked (through blood tests). Various medications are taken to stimulate egg production. Multiple eggs are desired as some may not develop properly after retrieval.
STEP TWO – Egg retrieval
A needle is passed through the upper vaginal wall and follicular fluid is removed. And eggs present in the fluid are identified and isolated. The eggs are then put into nutrient media and cultured in an incubator.
STEP THREE – Fertilisation (and embryo culture)
Active sperm is mixed with or injected directly into the egg(s). They are assessed after 16-18 hours for fertilisation.
STEP FOUR – Embryo quality
Embryo quality is assessed based on the size and development level. Only the healthiest embryos are transferred. This is the stage at which PGD can be carried out.
STEP FIVE – Embryo transfer and implantation
Embryo(s) are transferred into the uterus of the woman under ultrasound guidance. This usually happens between day 3 and day 6. Usually only one embryo is transferred to reduce the chance of multiple pregnancy.
STEPS OF PGD (between steps three and five of IVF)*
STEP ONE – Embryo biopsy
A trophectoderm biopsy can be carried out on the successfully fertilised eggs after 3-6 days (from the blastocyst of about 100-150 cells). The cells are taken from what would become the placenta, so the process shouldn’t harm the embryo.
STEP TWO – Embryo testing
The DNA of the cells taken in the biopsy is tested for the specific genetic condition.
STEP THREE – Embryo transfer
Of the suitable embryos (without the genetic condition), one is transferred into the uterus of the woman.
Any remaining suitable (condition-free) embryos can be frozen for further used.
Any unsuitable embryos will be disposed of, or can be donated for medical research.
Why is PGD use a Socioscientific Issue?
The use of PGD allows at-risk parents to screen for specific genetic conditions or abnormalities in their future child. Although this process can prevent severe disorders in children and future adults, it is still a highly controversial socioscientific issue.
Some areas of controversy due to biological implications include:
There are risks of ovarian hyperstimulation syndrome
No guarantee of the embryo being free of the genetic condition
Key areas of socially controversial implications are:
The devaluing of human life
The slippery slope to creating a perfect child
The religious aversion — the fear of “playing God”
Biological Implications
The continued risks of genetic disorders are not as significant as the risk of OHSS, as OHSS poses an increased threat to women undergoing the process, while the risk of genetic disorders is present irrelevant of the PGD process (and even decreased due to the process).
Ovarian Hyperstimulation Syndrome
The early stages of IVF/PGD involve the use of ovary-stimulating drugs to stimulate egg growth. There is a risk of ovarian hyperstimulation syndrome (OHSS) if the hormone doses are too high. This results in swollen, painful ovaries. In mild cases, nausea, bloating and slight weight gain are noticeable. These symptoms worsen, and vomiting, calf and chest pains, shortness of breath, and darker/ceased urine output are all symptoms of severe cases of OHSS. In extreme cases there is risk of death.*
A significant proportion – around 1 in 20 women* – who undergo IVF experience OHSS. By potentially increasing the number of women who undergo IVF and PGD, we are likely increasing the number of women who will suffer from OHSS. Particular care must be taken in the calculation of fertility drugs.
Continued risk of genetic disorder(s)
Despite the entire point of the process of PGD being to ensure the embryo is free of the genetic conditions, only one genetic condition can be tested for during a cycle and even that testing is not 100% accurate. Between 2% and 10% of PGD tests identifying whether an embryo has a specific genetic condition do not give accurate results*. According to William Kearns (director of the Shady Grove Centre for PGD) “Even the highest quality PGD fails to identify 10 percent of defective embryos”*. This can have a significant lifelong impact on the child from biological issues caused by their genetic condition, such as cancer (BRCA gene) or severe loss of mental and physical capabilities (Huntington’s Disease)*.
There is a risk that other genetic disorders/abnormalities will be present in the selected embryo. If one disease was tested for, and an unaffected embryo chosen, the new embryo could still have any other number of genetic conditions.* This is significant because unknowingly choosing an differently affected embryo will also have a severe impact on their life.
Social Implications
The risk of devaluing the lives of those living with genetic conditions has more significant (or at least more immediate) implications on our society, as it undermines and creates hate towards people in our society today. The religious issue of whether it is playing God also does this, but to a lesser extent. The disposal of embryos has the least significant impact, as no conscious, self-aware person is majorly affected*. Overall these social implications are more significant than the biological implications discussed, as they have a more permanent, harmful effect on our society now, and in the future.
Devaluing of Human Life
The process of PGD risks devaluing human life by devaluing the existence and potential of early embryos.
Any embryos carrying the genetic conditions tested for or with other developmental problems restricting their use in this process are discarded. According to Daily Mail Australia, “3.5m embryos have been created since 1991 but 93 per cent are never used”*. By devaluing these millions of early stage embryos (affected or not), we are risking movement towards normalising abortions at later and later stages. This in itself is a morally debated topic, as many religions have their own teachings on what constitutes a human life, and therefore what is involved in ending it*. It is important to consider these social implications of increased numbers of terminated embryos and potentially later pregnancies due to societal normalisation, regardless of religious beliefs.
Creating a Perfect Child and a Perfect Society
An issue with the discard of affected embryos (and with the process as a whole) is that it clearly sends the message that people without these genetic conditions are preferred over those with these conditions. It values the life of one potential person over the life of another. Creating this human ranking is dangerous*. We live in a world already filled with bias and stereotypes, and we are perpetuating them and adding to them the notion that people with specific conditions are an unnecessary burden to society. This could lead to increases in discrimination and hate in our society*.
The aim of PGD is to remove the chance of an affected child being born, thus decreasing the damaging gene in the gene pool. An extension of this is the eventual wipeout of specific diseases and conditions. This could cut costs for national healthcare. It could mean overall quality of life in NZ goes up. It could remove the need for carers and help ease the load on overworked hospital staff*.
But by aiming for an ideal, disease free society we devalue the lives of those living with disabilities (either due to lack of PGD use or by error in the process). If we do not let them be even implanted into the uterus, do we try to save them if they have health complications later? Do we put tax money towards caring for them?
There are clear benefits to aiming for disease-free society, but they do have a cost: deciding that some people are too much of a burden on society to deserve a life. The risks of societal hate and discrimination are the second side to an idealised coin.
Playing God
Many people in NZ are highly influenced everyday by their religious beliefs. This means that an increase of PGD use would have implications for these areas of out society. In many religions, embryos are considered human lives with a right to continue living. This means the creation and disposal of embryos should supposedly be left to God. A lack of education as to the benefits and positive societal effects of PGD in these churches/communities means that there is palpable hate and clear distain for the life-changing process. Although PGD can have negative implications, it does have many benefits for individuals and society. This hate is dangerous, and could cause decreased quality of life for those who avoid the process due to religious beliefs and lack of education on the matter.
Differing Opinions
Pro-PGD opinion: Daniel Stanley*
Daniel Stanley, a UK teacher, supports the use of PGD as he believes the suffering of those diagnosed with specific genetic disorders (or later health problems because of them) is too great to endure, so this preventative technology should be used.
He unfortunately had his sister pass away at age 28 due to a cancer caused by a BRCA gene. He knew he wanted a family, but did not want to pass on the gene to his children. His opinion is “If science has given me that power to do something about [the suffering caused by the cancer] then really I should use that power”, and he believes it is right for him to use that power to eliminate the gene from his children, and future generations.
He believes the damaging personal implications for those diagnosed with cancer outweigh the potential negative societal implications of eliminating affected embryos.
Anti-PGD opinion: Josephine Quintavalle*
NZ-born Josephine Quintavalle, of Comment on Reproductive ethics, said: “it’s a very big ethical step”. She believes that it pushes us down a slippery slope from eliminating embryos which will not survive to full term to eliminating embryos which may develop issues late in their adult lives and could push us further. Especially for genes such as the BRCA genes which can result in potentially curable diseases, well after childhood. In her words: “We should be looking for medicines that cure, not medicines that kill”.*
Her point links with the societal implications of devaluing lives which could be long and mostly healthy.