Frequently Asked Questions

Here is a list of frequently asked questions which cover areas such as how suitable donors are found, the stem cell collection process and other elements of our work.

Find more information about blood cancer and donating blood stem cells.

Learn more

About becoming a donor

Can I register while breastfeeding?

You can register as a potential blood stem cell donor while breastfeeding, however you will need to be deactivated on the register until you have stopped. It is best to wait until after you have stopped breastfeeding before registering as a potential blood stem cell donor.

If you are pregnant or have recently given birth and are not breastfeeding, then you need to wait until six months after your baby is born before you can register.

When will my donor card arrive?

When you register to become a potential blood stem cell donor with us, we send you a do-it-yourself swab kit with instructions and a pre-paid envelope for returning your swabs to us. Once we have received your swabs back, we will send you an email to acknowledge this.

Your swabs will then be analysed at our lab and your tissue-type will be determined – this process usually takes between 3-6 weeks. Once your swabs have been analysed, you will go live on the UK stem cell registry. You will then receive your donor card to confirm this. Your donor card can take up to 12 weeks to arrive, this is because we send them out in batches every few months to save on postage costs.

Can I register for a specific person?

When you register as a potential blood stem cell donor, you are added to the UK stem cell registry and are on standby to save the life of anyone in need of a blood stem cell donation. Many people are inspired to register after seeing the story of a particular patient, but it is important to understand and be comfortable with that fact that you could be a match for anyone, and that you could be their best hope of survival. We ask that everyone that registers is prepared to donate to anyone who they are a match for.

Can I register if I live outside the UK?

You must live pernamently in the UK to register with DKMS UK, but you can register as a potential blood stem cell donor in other countries. In addition to the UK, DKMS also registers potential blood stem cell donors in the US (, Germany ( and Poland ( If you live outside of these countries, you can see if there is a registry in your country on the World Marrow Donor Association (WMDA) website:

Who is eligible to become a potential donor?

Any healthy adult living in the UK, between the ages of 18-55 can become a potential blood stem cell donor and pre-registration is possible from the age of 17.

There are some exceptions. Before you register, please check that you are able to donate by looking at this list. We have listed the exclusion criteria which is put together by experts and doctors at DKMS and are necessary to ensure the safety of both patients and donors.

You can register as a potential blood stem cell donor if you have had a blood transfusion, as long as the blood transfusion was over 12 months ago and was given within Western Europe, North America, Australia or New Zealand. However, you cannot register if you have been told you may be at risk for Creutzfeldt-Jakob Disease.

Important Exclusion Criteria:

  • Heart disease (e.g. Coronary heart disease, previous heart attack)
  • Lung disease (i.e. Chronic Obstructive Pulmonary disease)
  • Blood disorders (i.e. Thalassaemia Major, Protein C, Protein S or Antithrombin deficiency)
  • Thrombosis
  • Neurological disorders (i.e. Epilepsy, Parkinson‘s disorder)
  • Cancer
  • Autoimmune conditions (e.g. Rheumatoid Arthritis, Crohn‘s disease)
  • Infectious diseases (e.g. HIV, AIDS, Hepatitis B and C)
  • Diabetes Type 1 and 2
  • Weight under 7 stone 12 lbs/50 kg
  • Obesity (i.e. body mass index (BMI) > 40)

Online registration: how does that work with the swab kit?

You can register to become a potential donor on our website here. Simply fill in the online registration form and we’ll send you a DIY swab kit. All it takes to know if you’re someone’s match - is a quick swab inside your cheeks. You can register online for a DIY swab kit and take your cheek sample at home and then post us your swab sticks in the freepost envelope provided.

The kit contains two swabs, which should be gently rubbed on the inside of each cheek for 60 seconds on each side, and held to dry for a few minutes. These should then be placed in the swab envelope provided and sent back to our office in the pre-paid envelope. We will then send them to our laboratory, who will determine your tissue type, and your details will be placed anonymously onto the register of potential donors with your unique donor number.

Are there any risks associated with blood stem cell donation?

Peripheral Stem Cell Donation – (method used in over 90% of donations):

A peripheral blood stem cell donation is performed as an out-patient procedure and you will not be required to have a general anaesthetic. This technique has been applied in medicine since 1988 and has been performed by DKMS (Delete Blood Cancer UK) since 1996. According to our most recent research, no known long term effects have ever been recorded for either the procedure of donating or for the G-CSF injections that you would receive prior to the donation.

Bone Marrow Collection – (method used in less than 10% of cases):

A general anaesthetic is necessary for the bone marrow collection. The risk of life-threatening complications during any general anaesthetic is estimated by doctors at less than around 1:50,000. After the collection, local wound pain and in some cases nausea can occur as an after-effect of the general anaesthetic. Furthermore, a risk of infection exists to the same extent as it does for any wound. There are no known risks associated with this procedure for donating bone marrow.

How does DKMS finance itself and where does money raised by DKMS go?

DKMS is a charity and therefore relies on monetary donations to cover donor recruitment costs. The cost of the registration for one potential donor is £40. Our operations and administrative costs are paid out of a reimbursement fee we receive for further testing of donors (once they are identified as a potential match) and for the stem cell donation itself. We are committed to working efficiently and at the highest professional level and undertake an annual financial audit.

How will the security of my data be ensured?

DKMS only records, processes and makes use of your personal data in accordance with your informed consent. We adhere to legal guidelines on the use of any data and only keep what is legally permissible and necessary in order to find a suitable stem cell donor.

The protection and security of your data is of paramount importance to us. We are registered and adhere to the Data Protection Act 1998 and ensure that all employees are fully up to date and trained in this Act. Your personal data will be stored in our secure DKMS database and only your anonymised data will be transmitted to registries to find out if you are a potential match for a patient (data such as HLA tissue characteristics, age and gender and donor number).

Why does registering cost money?

DKMS is a charity and therefore relies on monetary donations to cover donor recruitment costs. The cost of the registration for one potential donor is £40.

Tissue typing is the determination of your tissue characteristics from your swab through analysis by a laboratory. We have to fund all registration costs entirely through voluntary monetary donations. This is why we are grateful to those who are able to support us by making a monetary donation to cover the cost of their own registration, and also for those who contribute towards this cost.

Will I permanently lose my stem cells?

If you choose to donate some of your blood stem cells, you won't actually lose them. Your blood stem cells completely replenish themselves within 3-6 weeks. This has to be the best natural cure to this devastating disease, and it resides within every one of us!

I am homosexual, am I allowed to donate my stem cells?

Yes. We register anyone who is in good general health and aged between 17-55 years of age.

Can you donate stem cells several times?

Occasionally, donors donate stem cells more than once to the same patient. Very occasionally, a donor will be asked to donate more than once to different patients, although this very seldom happens. In all cases, once you have donated, you will be set to inactive on the database for a period of at least 2 years.

Why isn’t stem cell collection possible in all major clinics?

Collecting blood stem cells is a highly skilled procedure and unfortunately not all clinics have the technological capabilities and expertise needed to do this.

I am already registered. Can I still register with DKMS too?

If you are already listed with the British Bone Marrow Registry (BBMR), the Welsh Bone Marrow Donor Registry (WBMDR), or with Anthony Nolan, you should not re-register. We and each of these organisations register donors to one single UK registry.

Can potential donors cancel their confirmed and committed blood stem cell donation?

If you change your mind about being a potential donor, you are able to withdraw your consent at any time by contacting the DKMS team. However, if you have been contacted to be a match, you should be aware that withdrawing could have an impact on the patient’s health. In the preparation stage, a patient will receive treatment which prepares them for your stem cell donation. If a withdrawal occurs at this late stage, the patient may not be able to survive without the subsequent donation of your stem cells.

Finding matching donors

What are HLA characteristics?

As a potential stem cell donor, your tissue type will be matched using human leukocyte antigen (HLA) typing. HLA are proteins or markers found on all cells in your body. These proteins are used by your immune system to recognise which cells belong in your body and which cells do not. If these proteins do not match, the patient’s body would reject the given stem cells of the donor. A close match means that the patient’s immune system would recognise your blood system as its own. With more than 8,500 known characteristics that can occur in millions of combinations, finding a match is extremely rare.

Approximately two thirds of patients who need a transplant do not have a suitable donor within their family and rely on the register to find an unrelated donor. In these cases, the patient’s doctor will search for an unrelated donor. To be considered a match, the patient and donor must have at least 8 out of 10 tissue characteristics in common, but ideally should have 10. The rarity of having matching HLA tissue-type characteristics is the reason finding matching donors is so difficult.

What happens if no matching donor can be found?

If no matching donor is found for a patient, their consultant will try to help the patient through other forms of treatment. Typical treatments are (but are not limited to) chemotherapy and radiation therapy, although this will vary depending on the patient’s specific needs. For many patients however, a blood stem cell donation may be their only hope of survival.

What if I'm a match for someone

How will I know if I'm a match for someone?

If you are found to be a match for someone in need, we will be in touch as soon as possible, either by phone, text message, email, or letter. We will try to reach you by phone as the first point of contact. It is important that we have up to date contact information for you in case you are identified as a matching donor. You can inform us of any changes to your details using our form.

When will the collection take place?

It is hard to say exactly when your donation will take place because it strongly depends on the patient’s condition. In most cases you would be asked to donate 1-3 months after the confirmatory blood test. We will always give you 3-4 weeks advance notice. If there are any important dates when you know you cannot donate, we will always try to accommodate your schedule if you let us know in advance.

Will I be compensated for the time I take off from work?

If you are not covered by your employer, DKMS has a financial assistance programme that deals with lost wage compensation. If you are found to be a match and qualify for assistance, your co-ordinator will provide more information on this.

Where will my stem cells be collected?

Your stem cell collection will be scheduled at a hospital depending on where you live, and we will cover all of your travel expenses.

Am I allowed to get to know the patient?

Yes, you are eventually permitted to meet the patient (with the patient’s consent), although you may need a little patience. The UK law states that there should be a two year window of anonymity from the date of the transplant, with contact being permitted only after this time and only with the patient’s full consent. Contact can be established before this time via the team at DKMS in the form of anonymised letters. We do our upmost to help facilitate this process and understand its value to both the patient and donor.

This may differ for stem cell collections for patients from abroad as each country has its own regulations.

Who covers the expenses?

There will be no cost to you. When a donor is matched with a patient, DKMS will cover the costs (including any travel, meals, or accommodation expenses that may be necessary). DKMS will also cover the costs for a companion to travel with you to the hospital. A donor’s own health insurance will never be used.

Whilst it is extremely rare to require follow up care, if it is ever needed, the donor’s costs will also be covered by DKMS. Other than that we are not legally allowed to make any payments or rewards for the provision of tissues, including bone marrow or blood stem cells for transplantation.

Can I choose the method of my donation?

There are two possible ways you may be asked to donate and the method of your donation is determined by what the doctors believe will be best for the patient. We ask our donors to be comfortable with both methods of donation. If you are not willing to donate through either method, you should notify your DKMS Co-ordinator, so they can let the patient’s doctor know that you are only comfortable proceeding with one method of donation. The final decision on the method of donation will always be made by you as donation is voluntary.

How high is the probability of becoming a candidate for a blood stem cell donation?

For every donor there is only a 4-5% chance that they will match a patient within the next ten years, so it is a bit like winning the lottery. You will only become part of this figure if your tissue type is very closely matched to a specific patient in need.

Will I be asked to donate again?

Sometimes the patient relapses e.g. because the immune system does not accept the new donor stem cells. If this happens we might get in contact with you again to consider a second donation, or a donor lymphocyte infusion, which for the donor is similar to the PBSC procedure, but without the stem cell stimulation process.

Medical queries

Why is there a minimum weight requirement?

To be able to register as a potential blood stem cell donor, you must weigh a minimum of 7st 13lbs, or 50kg. This minimum weight requirement is in place to ensure your body can produce enough extra stem cells and to ensure your safety as a donor. The amount of stem cells that can be collected from the donor is calculated using their weight. If the potential donor is under the weight restriction, then unfortunately they will not be able to provide enough extra blood stem cells for the blood cancer patient.

Can I register with asthma?

Whether or not you can register as a potential blood stem cell donor with asthma depends on how severe it is and how it is controlled. You can register if it is controlled with inhalers or non-steroidal oral medication, such as Monteleukast. However, if your asthma requires oral steroids or steroid sparing agents, then you are not able to register. You are also unable to register if your asthma has meant you have been admitted to hospital with the need for IV steroids or emergency care in the past two years. Additionally, if you have ever been admitted to intensive care as a result of an asthma attack, then you are not able to register.

I have epilepsy, can I register?

If you have Epilepsy, whether or not you can register as a potential blood stem cell donor depends on the frequency of your seizures.

It is possible to register as long as you have been seizure-free for the past 12 months without needing medication. However, if you are currently requiring medication or have recently had a seizure, then you are unable to register. You are also not able to register if seizures are related to a problem with, or injury to, the brain.

Can I register if I have Diabetes?

This depends on which type of Diabetes a person has.

If someone has type 1 Diabetes, then unfortunately they are unable to register as a potential blood stem cell donor. This is because tablets or insulin injections are needed and the donation process could put the donor at risk.

If a person has type 2 Diabetes, then they can possibly register. To be able to do so, their Diabetes has to be controlled by diet and there should be no other risk factors such as obesity, high blood pressure and cardiovascular disease.

You are also unable to register if you have Diabetes Insipidus. This is because the process of donation poses a risk to the person donating their blood stem cells.

How am I insured as a donor?

The statutory accident insurance protects all persons who take special action in the interest of another person or in the interest of the general public. The insurance protection exists by law without the requirement of a separate insurance and covers blood donors and donors of endogenous tissues. This statutory insurance protection therefore exists by law for you as a donor too. The stem cell collection process is insured, as well as also the trips to and from the collection clinic. Please contact us directly for further information.

Will an AIDS test be conducted during the tissue typing for the registration with DKMS?

At the point of registration, your mouth swab is examined and tested for the sole purpose of determining your tissue type. Therefore, no tests for specific infectious diseases are carried out at this time. If however, you are a match for a patient in need, we will need to ensure you have no infectious diseases that could be passed onto the patient. Therefore, it would be at this point that we would test your blood for diseases including HIV and chronic Hepatitis B and C.

What happens if I become/am pregnant?

You can register with us as a potential stem cell donor before, during or after your pregnancy. You will not however be eligible to donate during and for 6 months after your pregnancy, or during the time in which you are breastfeeding. We ask all females who have registered to inform us if they become pregnant so that we can temporarily deactivate them on our database for the duration of their pregnancy.

Will my existing medical condition prevent me from donating?

We take the health and safety of our donors very seriously. All donors are required to complete a health history questionnaire before proceeding. Any medical concerns are reviewed by a doctor to fully assess your ability to continue as a donor. Depending on your health status, it is possible that you may be deemed temporarily unavailable to donate, or need to be permanently removed from the registry.

About the collection process

What is G-CSF?

G-CSF (granulocyte-colony stimulating factor) is a naturally occurring growth hormone that stimulates the production of stem cells in the blood of the donor before collection. Donors donating via peripheral blood stem cell collection receive injections of G-CSF for four days prior to donation.

How will I be prepared for the blood stem cell collection?

Before the collection, you will be examined thoroughly by a doctor to ensure that you are in good general health. This comprehensive examination ensures that the stem cell collection will take place in as risk-free a way as possible, for you and for the patient.

Before the stem cell collection, you do not need to comply with any particular rules of conduct or limitations. However, you should avoid any and all risks that could lead to illnesses or serious injuries which would subsequently put the stem cell donation at risk.

How does the patient feel when she/he is back at home again?

The aim is that the patient can lead a normal life after he/she has been discharged from hospital and is back home. Initially however he/she must follow certain rules in order to reduce the risk of infection (including staying away from large crowds etc.). For some patients, side effects can occur for longer periods of time and these can include skin rashes, hair loss, and a low level of saliva and tear production.

What are the first signs of a blood stem cell transplantation’s success?

Two to four weeks after a transplant, an increase in the patient’s white blood cells would be the initial indicator that the new stem cells were fulfilling their task and forming healthy blood cells. With a continual increase in the white blood cells, the chances of a complete cure increase too.

Where is bone marrow taken from in the second method of collection? Is it near my spine?

No, the bone marrow is not taken from anywhere near the spine. It is extracted from the back of your hip bone. This alternative method of extraction is the least often used (10% of cases).

Can my blood stem cells transmit diseases that the patient did not have before?

If you are a match for a patient you would have numerous medical assessments before the donation and will be screened thoroughly to ensure you are a completely suitable candidate.

What complications can arise for a patient who has received a blood stem cell donation?

Complications during the preparatory phases generally occur in the form of the known side-effects of chemotherapy and radiation therapy, such as nausea and regurgitation. During the initial period after the donation, a higher risk of infection generally exists since the patient’s immune system is strongly weakened after the preparatory phases and it can only recover again gradually. Unfortunately, setbacks can also occur because, in rare circumstances, not all cancer cells were destroyed.

That means that a renewed outbreak of the Leukaemia can occur again even after the donation. It can also be that the new stem cells prove to be incompatible with the patient’s own body tissues and this subsequently leads to a reverse rejection reaction. This complication (Graft-versus-host Disease) can occur in various levels of severity. However, it can often be treated successfully. If the donor’s stem cells do not grow or if it leads to a relapse of the disease, the donor might be asked whether he/she is willing to provide another stem cell donation.

How high are the chances of survival after a stem cell donation?

For 40-80% of patients who have a donation, the treatment is successful. The survival time after a donation depends on many different factors including the age and health condition of the patient, the timing of the donation, the type of underlying disease and on the emergence of potential complications.

Can I choose the method of my stem cell donation?

There are two possible ways you may be asked to donate some of your blood stem cells. The method of your collection is determined by what the doctors believe will be best for the patient and your individual choice. The final decision on the method of collection will always be made by you, as stem cell donation is entirely voluntary.

Why do people need blood stem cell donations?

In many cases, a blood stem cell donation is needed as a treatment for myeloma, lymphoma, or a form of leukaemia, such as acute lymphoblastic leukaemia, acute myeloid leukaemia, or chronic lymphocytic leukaemia. They are also given to patients who suffer from diseases of the hematopoietic cell system. These diseases can include various forms of leukaemia and lymph node cancers, severe aplastic anaemia, serious congenital immunodeficiency, and other diverse diseases of the red blood cells.

Working / volunteering for DKMS

How can I volunteer at DKMS

If you are interested in volunteering at our office in Chiswick, and can spare one or two days a week, we’d love to hear from you!

Just email us at for more information.

About DKMS

What does DKMS do?

DKMS is a global organisation dedicated to the fight against blood cancer. DKMS operates in the UK, Germany, USA, Poland and Spain. Together we have built a worldwide organisation, supported by more than 6.3 million potential lifesavers. Our vision is to provide every blood cancer patient with a matching donor or help with access to treatment – around the globe. We want to see our vision to delete blood cancer become a reality by recruiting, retaining and motivating potential blood stem cell donors globally to saves patient's lives. We are a registered UK charity.