Family limit for donated sperm and eggs
The 'Donating sperm and eggs: have your say' consultation closed on 8 April 2011. The information on this page is presented as it was during the consultation period and releates to the landscape of donation at the time.
See the consultation findings, and the current policies around sperm and egg donation in the UK:
- Clinics must ensure that sperm or eggs from a donor are used to create no more than 10 families.
- Donors can specify a lower limit if they wish.
- There is no limit on the number of children within each family.
- Sperm imported from abroad may be used for more than 10 families worldwide (ie, the family limit only applies in the UK).
We set a family limit to minimise the possibility of two children from the same donor having a relationship with each other without knowing they are genetically related. This is a concern both because of the emotional effect of the couple discovering they are related and because of the increased risk of them having children with health problems.
The current family limit is also based on the perceived social and psychological interests of donor conceived people and their parents in maintaining a relatively small number of siblings.
In practice, the family limit is only relevant to sperm donation. Sperm can be donated relatively easily and in larger quantities than eggs and it can be frozen and moved around the country efficiently.
Because of the medical intervention associated with egg donation and the relatively low number of eggs that can be collected each time, women are unlikely to donate their eggs more than a few times.
"Less than 1% of donors create 10 families. On average sperm donors create one or two families, with one or two children in each family..."
Keeping within the family limit is straightforward if a clinic recruits donors and uses the sperm or eggs for their own patients. However, some clinics – particularly sperm banks - recruit many donors and pass the sperm onto other clinics within the UK. These recruiting clinics are responsible for ensuring that the 10 family limit is not exceeded and have procedures in place to do so, based on guidance in our Code of Practice.
We know that there are some operational difficulties with how clinics monitor and enforce the limit. This will be addressed with clinic staff and other stakeholders alongside this consultation. Addressing these difficulties may help clinics to maximise the use of donations.
What do we know about donors and how their donations are used?
The majority of egg and sperm donors registered since the removal of donor anonymity in 2005, are happy for up to 10 families to be created from their donation.
- around 80% of newly registered donors did not specify a lower limit
- 16% of newly registered donors limited the use of their donation to just one family - this is likely because they donated to help a friend or family member
- the proportion of egg and sperm donors limiting their consent follows a similar pattern.
The majority of donation clinics think that most donors (apart from those donating to a friend or family member) would be prepared to donate to more than 10 families, a view supported by our own interviews with a small number of donors.
Is the family limit ever reached?
Less than 1% of donors create 10 families. On average sperm donors create one or two families, with one or two children in each family (based on donors who are happy for 10 families to be created, who registered between 2006 and 2008).
The number of families created may be affected by the following:
- 19% of sperm donors registered with the HFEA are never used, perhaps because donors withdraw their consent or patients do not choose them
- a lot of donor sperm does not result in pregnancy. The success rates for IVF and DI (donor insemination) are around 32% and 14% respectively for women under 35 (and less for older women).
- on average, clinics use sperm from one donor to treat only six patients, with an average of two cycles of treatment per patient
- sperm is sometimes imported from overseas sperm banks to treat specific patients (around 20% of sperm donors) - these donors may be happy for 10 families to be created with their sperm, but their sperm may only be imported for one patient.
"As part of this consultation we will aim to find out more about the impact of donor-conceived people having multiple siblings and the impact this has on donors’ own children."
The majority of sperm donations rarely result in 10 families. Any rise in the family limit would unlikely lead automatically to an increase in donor supply unless operational difficulties are addressed.
There are two main considerations when thinking about whether the limit should be raised, lowered or kept the same:
- the risk of two children from the same donor having a relationship with each other without knowing they are genetically related
- the psychological effects on donors and donor conceived people.
Risk of two children from the same donor having a relationship with each other without knowing they are genetically related
It is possible for anyone, from the age of 16, who intends to enter into an intimate physical relationship, marry or enter into a civil partnership, to find out, from the HFEA, whether they are genetically related to one another. But this depends on the person knowing or suspecting they are donor conceived.
The family limit is important to minimise the risk of two people born from the same donor, who do not know they are donor-conceived, having a relationship with each other.
Other countries approach this risk in a different way:
In the Netherlands there is a 25 children limit based on the principle that children from sperm donors may have, at most, a similar risk as children in the general population for having a relationship with a naturally conceived unknown half-sibling. This was calculated on the basis of specific data about the Dutch population and included figures on chance of having an unknown half-sibling, the average number of children parents have, the chance for donor conceived children to have children themselves, age and geographical factors determining the likelihood of meeting a partner in the district of a donor bank, and the size of the population being served by the donor bank
The American Society for Reproductive Medicine recommends that the limit should be based on the population from which the donor is selected and the catchment area that might be served by a particular donor. For example, in a population of 800,000 a donor should be used for no more than 25 pregnancies to avoid an increased risk of unintentional relationships between two genetically related individuals.
The risk depends on:
- how widely sperm from one donor is used (ie, if all samples are used at one clinic or at a number of clinics across the UK)
- the population of the area where the donor treatment is provided
- how mobile the population is (sperm from one donor may be used just at one clinic in a low population area, but this only presents an increased risk if the children born from that donor reside in the same area).
Outcomes of treatment with donor sperm in the UK, from donors who have reached the 10 family limit in the last few years, indicates that:
- families created from the same donor live a median of 36 miles away from each other
- children have been born as far as Atlanta, Calvados, Florida, Islamabad and Sydney
- the median number of families per town is 2.7 and a maximum of five families live in the same town (by which we mean the same town as where the donation took place) – there are three such cases: London (population over seven million), Bristol (population 421,300) and Glasgow (population 580,690)
- it is not known whether children from these families will remain in the same place as they get older.
It appears that risk of unintentional relationships between donor conceived children is low, and it may also be reduced with increased openness around donor conception. It is likely that the risk would probably remain low unless the limit was increased greatly.
Psychological effects on donors and donor conceived people
Some people feel that it is in the interests of donor conceived people (and their parents) to have a small number of genetic siblings and that the limit should be in line with the number of people a donor can have a meaningful relationship with. This is based upon the assumption that all people born in these circumstances know that they are donor-conceived.
As part of this consultation we will aim to find out more about the impact of donor conceived people having multiple siblings and the impact this has on donors’ own children.
Factsheet - key points and summary
This factsheet provides a summary of the ‘family limit’ section of the full consultation.
- Family limit factsheet (200 Kb)
Page last updated: 20 January 2011