Having Children- Young Adults
should I have a baby?
The decision to have children can be huge in anyone’s life. Everyone has to decide for themselves whether they want to have children or not. Some people at risk of HD, or who have the changed HD gene, decide they do want to have children, as this is part of a normal life and they’re prepared to take the risk. Most hope that by the time their children grow up, there will either be a cure for HD, or better drugs to manage the symptoms. Others decide not to have children because they don’t want to burden their children with the risk of HD.
If you are at risk of HD, or you carry the changed gene for HD, and you wish to have children there may be additional areas for you to consider. The two main concerns most people have are that: -
(i) You may pass on the risk of developing HD to your children, and
(ii) You may be anxious that you will develop HD and your children will experience living with a parent who has the illness.
Who can I speak to about having children?
There are many people who are available for you to talk to regarding your decision about having children. These people may include your partner, family, friends or HDSA/NYA members. If you require specialised information a genetics specialist can help you make the right decision for you and your circumstances.
What is the genetic risk to my children?
If you are at 50% risk of having the changed gene, then your children are at 25% risk of having the changed gene. This means they have a 1 in 4 chance of having the changed gene for HD.
If you find that you have the changed gene, your children are at 50% risk of also having the gene, and developing HD in the future. This means they have a 1 in 2 chance of having the changed gene.
What options are there to reduce a child’s risk?
There are a number of options available to reduce the risks of having an at risk child. These include: -
Preimplantation Genetic Diagnosis (PGD)
Prenatal testing involves testing a foetus in the early stages of pregnancy to see if it has the changed gene for HD. There are two methods used to do this; chorion villus sampling and amniocentesis.
If the foetus does not have the changed gene then the decision to carry on with a pregnancy is straightforward.
If the foetus is found to carry the changed gene there are two options available to you: -
- Terminating the pregnancy - which may be a very emotional, difficult and challenging decision to make.
- Continuing with the pregnancy with the knowledge that the foetus has the changed gene. This is further complicated by the fact that your child will be born with the certainty that he or she will develop HD in the future, and they will have been denied the opportunity to decide whether to have the test as an adult or not.
Exclusion testing tends to be used when a person is unsure about their status and wants to remain at 50% risk. It involves taking blood samples from three generations of your family – from you, your foetus and your affected parent. This can be a problem as you may have lost contact with your parent, or your parent may be deceased. The test tells you if you and the foetus have inherited the same chromosome 4 from your affected parent. It will not tell you whether the gene on this chromosome is the changed gene for HD, or if it is the normal gene.
A major disadvantage of Exclusion Testing is that there is a risk of terminating a healthy foetus.
preimplantation genetic diagnosis
This is a procedure which uses In-Vitro Fertilisation (IVF) to fertilise a woman’s eggs with her partner’s sperm in a laboratory. The embryos are then tested for the changed HD gene. Only embryos that do not have the changed gene are implanted into the womb. This means the baby will be born with no risk of developing HD. Any remaining unaffected embryos can be stored for later use as required.
However, like all IVF procedures the success rate is quite low (1 in 5) and can be a lengthy and emotional process. It may also involve some expense.
This method uses a donated egg or sperm in place of the affected parent.
Some people who are at risk of HD and do not want to pass on any risk to a child, or to use the technology outlined above, but do want to have children in their lives decide to adopt and bring up children who are not biologically related to them. If you are at risk of HD, or have the changed gene, it will be important to think about how the possibility of you becoming unwell may impact on any child you adopt. This is something an adoption agency would talk with you about in more depth.