Who is eligible to become a potential donor?

Any healthy adult between the ages of 17 and 55 can become a donor. If you are already on our register, it is not necessary to be added again. If you suffer or have suffered from a chronic illness or any other severe illness or regularly take medication, please discuss your case with DKMS.

The most important exclusion criteria are:

Weight under 7 stone 12lbs/50kg

The number of stem cells that can be collected during the donation process depends on the weight of the donor: if the donor has a higher weight, it is generally possible to collect more stem cells. If the amount of transplanted stem cells is low, the chances of a successful transplantation usually decrease, too. This is why there is a need for a minimum weight.

If the donor has a low weight, the amount of stem cells collected during the donation process can be so low that it impacts the success of the transplantation. Therefore, a donation/registering in our donor center is not sensible if the weight is significantly below 7 stone 12lbs.

Obesity (e.g. body mass index (BMI)>40)

For registering as well as for donating there is a maximum Body-Mass-Index (BMI) limit of 40.

This is because of multiple reasons: While a stem cell donation is harmless for healthy people, there are health risks if the donor suffers from other pre-existing risky conditions. Severe obesity is unfortunately one of these risk factors.

Severe obesity is problematic because both donation processes present a threat on the donor’s health: On the one hand, a donor with obesity has a higher risk for complications during anesthesia. On the other hand, the peripheral stem cell donation is not without unforeseeable risks, such as the difficulty to correctly dose the necessary medication, which also increases the side effects. Moreover, the bone marrow harvest might be impossible due to anatomic reasons.

The rate for complications unfortunately increases with severe obesity. The maximum weight limit is not intended to discriminate against certain groups of people, but only has the intend to protect the health of our donors, which is our greatest responsibility.

Severe illnesses of the central nervous system or mental illness

As with many diseases, the eligibility as a donor depends on the severity of the depression/anxiety. First of all, the question arises whether the potential donor is limited due to their illness and how resilient they are in their everyday life. The donation process is an additional mental burden, which has to be managed on top of everything else.

It is not only the question whether the donor will be able to reliably come to the donation appointment, but also how they can handle the situation after the donation. After all, they would gain a seriously ill “blood relative” through the donation and many donors really worry about their patient.

Particular concerns also arise, because many psychotropic drugs cause changes in the blood count. Especially neuroleptics are problematic in this regard, making it impossible to donate stem cells. If suffering from severe psychological illnesses, it is unfortunately not possible to register as a donor. Those illnesses include severe depression requiring treatment, borderline syndrome, any form of psychosis, schizo-effective disorders, and bipolar/manic affective illnesses.

It is possible to register as a donor, if suffering from a “mild” depression, receiving treatment for a limited amount of time and feeling well enough to manage the everyday life. This applies to donors whose medication contains less problematic substances, such as Citalopram or Fluoxetine.

Systematic autoimmune diseases or other severe chronic illnesses (e.g. diabetes or rheumatism)

It is problematic to register donors with diabetes mellitus type I in regards to protecting the donor as well as the recipient.

Diabetes mellitus type I is an autoimmune disease which leads to the destruction of the insulin-building cells of the pancreas. Since the transplanted cells are cells from the immune system, it can not be excluded that the disease will be transmitted to the patient. Because the health of the patient is already very weak, it is impossible to say which effect the disease would have on them. Severe complications are very likely.

Additionally, due to the increased blood sugar level, diabetes can cause – to a varying degree - consequential damages of the nerves and blood vessels. We do not want to risk a worsening of the disease through the stem cell donation.

This is why people suffering from diabetes are not eligible as a donor.

It is not possible to register as a stem cell donor if suffering from a rheumatic disease, even if the potential donor is currently not experiencing any symptoms. Rheumatic diseases include rheumatic arthritis, Bekhterev´s disease, and Juvenile Arthritis. The reason for excluding people suffering from those conditions is that they are autoimmune diseases.

During the stem cell transplantation, cells of the immune system are transmitted onto the recipient, leading to a risk of a possible negative reaction in the body of the recipient. Because the recipient is already physically burdened due to their disease, the chemo therapy to prepare for the transplantation, and the transplantation itself, a negative autoimmune reaction could be potentially fatal. This is the reason why it is not possible to donate stem cells and therefore to register as a stem cell donor if suffering from autoimmune diseases, including diabetes mellitus type I.

Cancer (including being cancer-free, but having had cancer in the past)

Unfortunately, we cannot register people who were suffering from a malignant disease in the past as stem cell donors.

Anybody who has suffered from a malignant tumor (explicitly: suffered from a not clearly benign tumor), is not eligible as a blood or stem cell donor. This does not depend on the success of the therapy or on how long in the past the cancer occurred.

Addictive disorder (alcohol, illicit or prescription drugs)

The occasional consumption of marihuana or cannabis does not influence the eligibility as a donor. However, we have to stress that this only applies to occasional consumption.

A reason for that is that a donor’s reliability has to be questioned if any kinds of drugs are used regularly. We do not predict a medically relevant endangerment, however an unreliable donor is highly problematic, because stem cell transplantations are realized on a tight schedule to not endanger the life of the patient.

It is important for us to know which kind of drugs are consumed and for how long. If the drugs have been consumed for a long period of time, it might be better not to register as a donor. If that is not the case and if the potential donor is capable and willing to stop consuming, they may register as stem cell donor.

Severe heart diseases

Registering as a donor and donating is possible if suffering from well-regulated high blood pressure or a mitral valve prolapse, if there are no health problems stemming from the condition. The same is true for an exceptionally high or low resting heart beat, as long as it is still steady.

Most of the other heart diseases that require treatment or at least monitoring unfortunately prohibit the eligibility as a donor because they greatly increase the risk of complications during the donation. Those conditions include cardiac dysrhythmia, damage to the vascular walls, arteriosclerosis (especially if medication with anticoagulant drugs is necessary), heart attack, strokes, or structural defects of the heart such as valvular defects. If you have questions concerning any other condition that requires treatment, please make a specific enquiry.

Severe lung diseases

Generally speaking, only healthy persons are eligible as a donor. Concerning chronic lung diseases, including diseases in the beginning stages, there is a risk of damaging the lung further during the donation. Autoimmune diseases also bear the risk of transmitting the condition onto the recipient. Many lung diseases also increase the anesthetic risk. Persons suffering from a frequent or consistent dyspnea are not eligible as a donor.

Severe kidney diseases

Generally speaking, only healthy persons are eligible as a donor. Concerning chronic kidney diseases, including diseases in the beginning stages, there is a risk of damaging the kidney further during the donation. Autoimmune diseases also bear the risk of transmitting the condition onto the recipient.

Severe tropical infectious diseases, particularly Malaria

Generally speaking, only healthy persons are eligible as a donor. Concerning chronic kidney diseases, including diseases in the beginning stages, there is a risk of damaging the kidney further during the donation. Autoimmune diseases also bear the risk of transmitting the condition onto the recipient.

Infectious diseases like HIV, Hepatitis B or Hepatitis C, HTLV and Syphilis

Every pre-existing infectious disease can be transmitted onto the recipient during the donation. This is also the case if the donor does not have any symptoms because their immune system has been able to control the disease. However, the patient does not have a working immune system at the time of the transplantation so that they are not protected from infectious diseases.

Diseases of the hematopoietic System (blood disorders)

Diseases of the blood and the immune system are problematic, because the stem cells of the hematopoietic system and the immune system are transmitted through the transplantation. Our goal is to make the transplantation as successful as possible. Conditions that have developed during the lifetime of the donor can also be transmitted during the transplantation, because the transplant includes mature cells of the immune system. Additionally, some diseases can increase the risk of the donation for the donor. Examples hereof are a higher risk for thrombosis or bleeding if the donor has a condition affecting the coagulation factors.


You are eligible as a stem cell donor without additional consultation if the following criteria (see brackets) apply to you:

ENLARGED THYROID/UNDERACTIVE THYROID (HYPOTHYROIDISM)/HASHIMOTO’S THYROIDITIS (STABLE AND SYMPTOM-FREE; ALSO WHEN TAKING THYROID HORMONES OR IODIDE; NO GRAVE’S DISEASE)

In many cases, an enlarged thyroid (goiter) is caused by a lack of iodine (iodine-deficiency goiter). A lack of thyroid hormones can also lead to an enlarged thyroid. Here, the thyroid tries to compensate for the low hormone production by creating more tissue. If you are symptom-free and your thyroid hormones are well adjusted, neither issue poses a contraindication for a donation.

If the cause of the hypothyroidism is a thyroid operation, this does not present an obstacle for inclusion in our database as long as this was not due to Grave’s disease or thyroid cancer.

If the cause for the hypothyroidism is an autoimmune disease of the thyroid (Hashimoto’s thyroiditis), the potential donor may be permitted to donate stem cells – at least temporarily – only through surgical collection from the pelvic bone. This would be clarified in more detail once the donor is considered for a patient. If the patient has an underactive thyroid without any other prior thyroid disease, this is likewise not a problem.

Hashimoto’s thyroiditis is among the few autoimmune diseases that do not present an obstacle for stem cell donation. However, it is important that the thyroid is well controlled with medication. In addition, it may be that the potential donor – at least temporarily – can only be permitted to donate stem cells via surgical collection from the pelvic bone. This would be clarified in more detail once the donor is considered for a patient.

Grave’s disease is an autoimmune disease of the thyroid that results in an overproduction of thyroid hormones (hyperthyroidism). In this case, a donation can be problematic both for the recipient as well as for the donor.

High blood pressure (stable and well-controlled)

High blood pressure generally does not impact the stem cell donation if the condition is well-regulated with drugs or through an adapted diet. Furthermore, the high blood pressure should not have caused any damages to the eyes, heart or vessels. If the high blood pressure is well-regulated, it does not impact the eligibility as a stem cell donor.

Hay fever, mild asthma (without attacks), food allergy

It is possible to donate stem cells if the donor is suffering from an allergy (including food allergies, hay fever or drug allergies), with the exception of severe allergic reactions (e.g. allergic shocks or Quincke's Edema) in the past. In this case we would like to ask you to contact us, because it may impact your eligibility as a donor.

Unipolar depression (without any limitations in the everyday life))

As with many diseases, the eligibility as a donor depends on the severity of the depression. First of all, the question arises whether the potential donor is limited due to their illness and how resilient they are in their everyday life. The donation process is an additional mental burden, which has to be managed on top of everything else.

It is not only the question whether the donor will be able to reliably come to the donation appointment, but also how they can handle the situation after the donation. After all, they would gain a seriously ill “blood relative” through the donation and many donors really worry about their patient.

Particular concerns also arise, because many psychotropic drugs cause changes in the blood count. Especially neuroleptics are problematic in this regard, making it impossible to donate stem cells. If suffering from severe psychological illnesses, it is unfortunately not possible to register as a donor. Those illnesses include severe depression requiring treatment, borderline syndrome, any form of psychosis, schizo-effective disorders, and bipolar/manic affective illnesses.

It is possible to register as a donor, if suffering from a “mild” depression, receiving treatment for a limited amount of time and feeling well enough to manage the everyday life. This applies to donors whose medication contains less problematic substances, such as Citalopram or Fluoxetine.

Iron-deficiency anemia (treatable with iron supplement)

Concerning the frequently occurring iron-deficiency anemia, the determining factor is the hemoglobin level. If the level is frequently below 11.5 mg/dl for women and 13.5 mg/dl for men, this does cause problems for donors. However, if the iron supplement is well-tolerated and the iron level and the hemoglobin level are okay, the donor would still be eligible for stem cell donation.

Basal cell carcinoma and cervical carcinoma in situ

Basal cell carcinoma and cervical carcinoma in situ do not impact the eligibility as a donor, if they have been removed completely and the control check-ups since have been without pathological findings.

The reason therefore is that in the cases of basal cell carcinoma and cervical carcinoma, it is not expected for the cancerous cells to spread (metastasizing).


The registration at DKMS is only possible for persons who are permanent residents of Germany. Potential donors from other countries can register at their local registries. You can find a lift of your national registries on www.wmda.info or www.bmdw.org.

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