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Your A-Z glossary on donor sperm and fertility treatment

Having a baby with donor sperm involves learning a lot of new terms. On this page, you can look up the definition of unfamiliar words and abbreviations.


Many countries have rules regarding the maximum age that you can have fertility treatment as a woman. The age varies from country to country and in some countries there is also a distinction between the maximum age at which you can get publicly funded fertility treatment and the maximum age at which you can have fertility treatment that you pay for yourself.

In the UK, for instance, the fertility treatment regulator HFEA recommends that funded IVF be offered to women until age 42 whereas there is no recommendation or limit for privately paid treatment.

Other examples include Denmark where you can get publicly funded fertility treatment until you turn 41. If you choose to pay for it yourself at a private clinic, you can get treated until the age of 46.

Other countries such as Spain, Greece and Cyprus have higher age limits for women seeking fertility treatment.

AMH is a glycoprotein hormone made by the granulosa cells located in the ovaries.

AMH tests have become the go-to method for most fertility clinics to determine a woman's ovarian reserve. That’s because the Anti-Müllerian Hormone is produced by the developing ovarian follicles (i.e., potential eggs) in adult females. The quantity and quality of a woman's eggs or developing eggs are referred to as her ovarian reserve. Higher AMH levels typically mean that there is a larger number of eggs compared to a low AMH value which indicates a lower number of remaining eggs.

The term anonymous donor refers to a donor whose identity is secret to parents as well as the children conceived with his sperm. The opposite donor type is what is commonly known as ID Release donors where children can learn the identity of their donor when they reach legal age. Anonymous sperm donation is not allowed in many countries, among them the UK, the Netherlands and Germany.

However, in many cases such donors are in fact not anonymous because there is often a lot of information about the donor available to parents and children. When combined, information about a donors blood type, occupation, nationality, education becomes identifying in a legal sense. Also, the term "anonymous" indicates that the donor is anonymous to the sperm bank which is not the case. That is why sperm banks do not use the term anonymous donors and instead opt for terms like "No ID release" or "Non-ID release".

Finally, the rise of consumer genetic tests and international DNA databases is jeopardizing the anonymity of sperm donors. This is something that is now discussed with prospective sperm donors in most sperm banks before they are approved as sperm donors.

Artificial insemination is a category of medically assisted reproduction where the sperm is inserted into a woman's vagina, cervix, uterus or fallopian tubes.

When performed by a fertility treatment professional, artificial insemination is carefully timed with the woman’s ovulation through hormone stimulation and ultrasound scans, thereby increasing the chances of pregnancy.

There are several different types of artificial insemination, but the most common is Intrauterine Insemination (IUI).

See Dominant inherited conditions.

See Recessive inherited conditions.

Azoospermia is a medical condition where there are no sperm cells in a man's semen. The lack of sperm cells can be caused by several factors including hormonal imbalances, genetic abnormalities, or blockages in the reproductive tract.

Men with azoospermia are unable to conceive naturally. However, in some cases, the cause of azoospermia can be treated, so the person is able to conceive a child. Treatment of azoospermia is done through medical procedures and often in combination with assisted reproductive technologies such as ICSI.

Barnrett refers to the term and legislation previously used in Norway to ensure that a donor does not exceed the allowed number of children per donor. However, as of February 1st 2020, legislation in Norway has changed and Norway now uses the term Pregnancy Slot like most other countries. You can read more about pregnancy slots here.

We all have mutations or defects in some of our genes, and these mutations can cause genetic disease – either in the person with mutated genes or in their children.

Whether someone develops the disease and becomes sick depends on many factors. One of them is mode of inheritance. The four main types of genetic inheritance are: autosomal recessive, autosomal dominant, X-linked recessive and X-linked dominant (see explanations of these terms elsewhere on this page).

CMV - short for Cytomegalovirus - is a herpes virus that is transmitted through saliva or body fluids. It is a common infection that most people get at some point in their lives and the majority of CMV infections are harmless.

You can read more about CMV and our CMV screening of sperm donors on our screening page.

The word cryobank typically refers to sperm banks, but it can also be a place for preservation and storage of other types of biological cells or tissue. The word ""cryo"" means ice cold or freezing and thus refers to the method of preserving the sperm cells at very low temperatures (see Cryopreservation).

Cryopreservation is a technique that preserves human tissue or cells by cooling them to extremely low temperatures. The prefix ""cryo"" means ice cold or freezing.

In recent years, it has become increasingly popular for people to use cryopreservation to freeze their own eggs or sperm to increase the chances of being able to have children later in life - what is also called social freezing. At sperm banks, cryopreservation is used to preserve the quality of donor sperm.


A word used by some people for the children conceived with the same donor who are growing up in separate families. ""Dibling"" stems from a combination of the words ""donor"" and ""sibling"". Other terms include donor half siblings or donor-conceived siblings.

A dominant condition arises when a child inherits one mutated copy of a gene from one of their biological parents. Unlike recessive conditions, carriers of dominant conditions will often be aware of the condition because it runs in the family. The age of onset and symptoms may vary even within the same family.

The full name for these types of genetic conditions is autosomal dominant inherited conditions. The word “autosomal” means that the mutated gene is not located on a sex chromosome (XX for women, XY for men), but on one of the remaining 44 chromosomes.

Common dominant inherited conditions are hereditary predisposition to breast and ovarian cancer (BRCA), Huntington’s disease and Marfan syndrome.

Donor profile refers to a collection of personal information about the donor. The range and depth of information varies from one sperm or egg bank to the next. In many cases, aspiring parents and donor-conceived individuals can read about the donor's hobbies, personality, occupation.

You can learn more about what kind of information we provide about our donors on the donor profile information page.

Double donation means using both donor sperm and donor eggs to conceive a child through fertility treatment. Double donation can be used in a variety of cases:

  • When both aspiring parents struggle with infertility
  • When a prospective solo mum is struggling to conceive (she will already be using donor sperm to form her family)
  • When avoiding genetic disease. People who suffer from a serious inheritable condition risk passing on the disease to their future child if they use their own reproductive cells. 

In the last case, double donation is typically considered when the other person in the couple is struggling with infertility.

Women suffering from endometriosis have tissue similar to the endometrium, the innermost lining layer of the womb, growing outside the womb.

Endometriosis can lead to inflammation and scarring. It is also often a cause of infertility because the growth of tissue can cause blockages in the fallopian tubes or damage to the ovaries and uterus.

In some cases, the condition may require that the person suffering from endometriosis receives surgery or reproductive treatment to conceive a child as natural conception can be difficult or impossible depending on the severity of the condition.

Many countries' legislation limits the number of families that a donor can help in that given country. This is also referred to as a pregnancy limit. However, because a donor can help families across borders, the number of families helped globally may exceed the number determined locally. There is no globally agreed-upon maximum for the amount of children conceived with a donor's sperm.

There are many different types of fertility tests that can assess a person's fertility or help determine the cause of infertility.

For women, tests may include gynaelogical examination, blood tests to check hormone levels, ultrasound scans to examine the uterus and ovaries or hysterosalpingography (HSG) to check the passage conditions in the fallopian tubes.

Men may undergo a semen analysis to assess sperm count, motility and morphology.

In cases of actual infertility, both men and women may undergo genetic testing to determine whether infertility could be caused by genetic factors.

The type of fertility test recommended will depend on individual circumstances and may involve a combination of tests.

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Genes are the basic building blocks of our bodies and contain the instructions for growth and development as well as maintenance of bodily functions. You can think of genes as the recipe for a human being or other living things.

Humans have approximately 22,000 different genes in two copies placed on 23 pairs of chromosomes. The sex chromosomes also determine our gender. For males, the sex chromosomes are XY and for females XX. We inherit one copy of each gene from our father and another copy of each gene from our mother.

Genetic screening refers to the process of examining a person's genes, typically to diagnose a potential genetic disorder or to determine whether the person carries mutations in their genes that can cause disease. There are several types of genetic screening, among others: diagnostic genetic testing, carrier testing, pre-natal genetic testing like the NIPT test and newborn screening such as the PKU.

With home insemination, the couple or woman using donor sperm to have a family carry out the treatment at home instead of at a clinic. During home insemination, you or your partner insert the sperm yourselves into the vagina with a small catheter or syringe.

The appeal of home insemination to many people is the fact that the treatment happens in the comfort of one's own home. Many like the idea of creating an intimate or romantic atmosphere at home instead of going to a fertility clinic.

It is good to know that home insemination is not allowed in all countries. Also, the chances of achieving a pregnancy can be lower compared to treatment at a clinic where insemination is carefully timed with the ovulation of the person being inseminated (see Artificial insemination for more information).

ICI (Intra-Cervical Insemination)
ICI, also known as Intra-Cervical Insemination, is a fertility treatment method that involves placing sperm in the vagina, close to the cervix, or directly in the cervix using a syringe.

With this treatment method, the sperm cells need to travel further to reach the egg than it is the case with the more common IUI method, where sperm is inserted directly into the uterus (womb).

ICI units may contain the naturally occurring ejaculate fluid and non-sperm cells. ICI sperm must be washed at the clinic before being used for intrauterine insemination, as only sperm cells should be placed inside the uterus. There will still be plenty of motile sperm cells. In some cases, ICI units can be used directly for other treatments, such as vaginal insemination.

Read more about treatment types on the dedicated webpage.

ICSI (Intra-Cytoplasmic Sperm Injection) is an advanced form of fertility treatment where a single sperm cell is injected into the egg with a tiny needle. After the injection, the ICSI process follows that of an IVF treatment, so many fertility clinics consider ICSI a form of IVF.

Following the fertilisation of the egg, the growth of the developing embryo is followed for a few days, and if deemed optimal, the embryo is placed in the womb of the woman.

ICSI (Intra-Cytoplasmic Sperm Injection) is typically used in cases of couples that struggle with severe male factor infertility or if they have had several failed IVF treatments. An ICSI treatment doesn’t require the sperm cells to swim well to reach the egg because only one sperm cell is selected and injected into the egg. For that reason, this method can be useful for men with low sperm quality who do not have the higher number of good swimmers required for other medically assisted reproduction techniques.

For the same reasons, ICSI is not used much when donor sperm is used for fertility treatment because the quality of donor sperm is so high, thus eliminating the need for ICSI.

ICSI is sometimes also referred to as micro-insemination.

Intra-Uterine Insemination (IUI) is a very common type of fertility treatment where the sperm is inserted in the woman's womb with a small catheter and in this way bypassing the cervix. The method of Intra-Uterine Insemination (IUI) is much more simple and less invasive than IVF or ICSI treatments where eggs are fertilised outside the womb in a lab and then placed in the uterus if the fertilisation is successful.

IUI is often considered the first treatment option for couples where there are no known factors that could severely affect their fertility.

Other forms of insemination exist such as Intra-Cervical Insemination (ICI) and Intra-Vaginal Insemination (IVI). In these treatment types, the donor sperm is placed even further away from the egg, thus making it necessary for the sperm cells to travel longer to impregnate the egg.

For IUI treatments you use processed sperm (what is also referred to as ""washed"" sperm). Inserting unprocessed sperm (also known as unwashed sperm) directly in the uterus may cause an allergic reaction in the form of anaphylactic shock.

Read more about the most common treatment types on this webpage.

In Vitro Fertilisation (IVF) is a fertility treatment in which an egg is fertilised with sperm outside of the body in a laboratory dish. Following the fertilisation of the egg, the growth of the developing embryo is followed for a few days, and if evaluated optimal, the embryo is placed in the womb in the hope of achieving a successful pregnancy.

IVF is commonly used to treat infertility caused by scenarios such as blocked fallopian tubes, male factor infertility, several failed IUI attempts or unexplained infertility. The process involves several stages including ovarian stimulation, egg retrieval (unless an egg donor is used), fertilisation, and embryo transfer.


A karyotype is a visualisation of an individual's set of chromosomes. Karyotypes are used for chromosome analysis, a type of genetic screening that examines the structure and number of chromosomes. The purpose of the screening is to determine if the person has a full set of chromosomes with a normal structure.

Conditions such as Down’s Syndrome, Turner's Syndrome and Klinefelter Syndrome are all caused by an abnormal shape or number of chromosomes.

An abnormally shaped chromosome does not necessarily pose problems for the individual him- or herself. But if the abnormality is passed on through the person’s sperm or egg cell, it can cause fertility problems with a high risk of miscarriage and serious problems with health, growth and development in the foetus.

"Known donor" refers to a person who donates sperm or eggs to someone they know. Typically, the donor is a friend of the person who wants a child. Choosing a known donor offers the opportunity of the future child having a relationship with the donor, but complications could arise later if the right arrangements and agreements are not made prior to conceiving the child.

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LGBT couple's search for a donor: From grey market to sperm bank

Hayley and Katja Schönberg considered using a private sperm donor - also known as a grey market sperm donor - before settling on using a sperm bank. Read about their journey on our blog.


Sperm morphology refers to a sperm cell's shape and size. Sperm morphology analysis is done by examining a semen sample under a microscope to determine the amount of abnormally shaped sperm.

MOT is short for Motile Total and refers to the concentration of forward-moving sperm cells in a millilitre of sperm. That is, how many ""good swimmers"" there are (see Motility for more information).

MOT is counted in millions per millilitre and donor sperm is available in several MOT concentrations. For instance, MOT20+ means that there are at least 20 million forward-moving sperm cells in a millilitre. The higher the MOT value, the more good swimmers per mililitre. However, it is important to note that MOT is not a quality parameter. It only refers to the concentration or the number of forward-swimming sperm cells. The quality of the sperm cells (their shape and ability to swim) is the same across all MOT types, only the amount of forward-moving sperm cells differs.

Donor sperm comes in multiple MOT types because different amounts of sperm cells are required depending on the fertility treatment you will be having. If you are doing IUI, most fertility clinics will choose to use MOT20 because the sperm cells need to travel to the egg themselves - compared to other treatments like IVF or ICSI where fertilisation of the egg happens outside the body.

Learn more about MOT here.

Sperm motility describes a sperm cell’s ability to move. A sperm cell needs to move in a forward-swimming motion to reach the egg during natural conception - as well as during several forms of medically assisted reproduction (for instance, IUI). Not all sperm cells move in a forward-swimming motion, and many cases of male infertility are caused by poor motility.

Some sperm cells move in small circles, others don’t move at all and then there are the sperm cells that swim forward – this third group possesses a quality called “progressive motility”. Sperm cells with progressive motility stand the best chances of making it all the way to the egg and fertilising it.

A No ID Release donor has decided that he doesn't want his identity to be revealed to children conceived with his sperm. Typically, that is the only difference between ID release donors and No ID release donors, although there can be slight differences from sperm bank to sperm bank in how they define each donor type.

In some places, No ID Release donors are also referred to as Non-Contact donors.

A Non-Contact donor has decided that he doesn't want his identity revealed to children conceived with his sperm.

See also the entry on No ID Release donors.

An open donor is a donor who has agreed to children conceived with his sperm learning his identity when they reach legal age - if they so desire.

In many cases, an open donor is the same as an ID Release donor, but there can be differences across sperm banks in how they define their donor types.


PCOS, or polycystic ovary syndrome, is a hormonal disorder that affects women of reproductive age. It is characterised by irregular menstrual cycles, excess androgen hormone production and the formation of small cysts in the ovaries.

PCOS can affect fertility by inhibiting or preventing ovulation, making it more difficult for women to conceive naturally. In such cases, assisted reproductive treatments such as hormonal treatment or In Vitro Fertilisation (IVF) might be needed to conceive a child.

See Family Limits for more information.

The legislation that governs the amount of families to which a sperm or egg donor can contribute (known as pregnancy limits) differs from country to country. In order to ensure that pregnancy limits are not exceeded, some treatment countries require that you purchase a Pregnancy Slot. In other words, a Pregnancy Slot acts as a quota, so there is a fixed and limited amount of pregnancy slots.

A Pregnancy Slot grants you the right to use a given sperm donor for your family, so you can use the same donor for potential siblings to your first child.

Having a Pregnancy Slot does not guarantee you the availability of sperm straws from the donor. For that reason, it is a good idea to buy donor sperm when booking your Pregnancy Slot to ensure that you will be able to use the donor for your family.

Learn more about Pregnancy Slots here.

A recessive condition arises when the mother and the father both pass on a mutated copy of the same gene to a child, causing the child to develop the condition.

We are all carriers of one or more genetic diseases, but most of us do not know our genetic carrier status – i.e., which diseases we carry in our genes - because most carriers of a recessive condition are healthy and have no symptoms. However, if you are a carrier and you have children with someone who is a carrier of the same condition, your children will have a 25% risk of developing the disease.

The full name for these types of genetic conditions is autosomal recessive inherited conditions. The word “autosomal” means that the mutated gene is not located on a sex chromosome (XX for women, XY for men), but on one of the remaining 44 chromosomes.

Common autosomal recessive inherited conditions are cystic fibrosis, thalassemia and spinal muscular atrophy.

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Secondary infertility is the inability to conceive or carry a pregnancy to term after having one or more successful pregnancies in the past. It can be caused by various factors including age, medical conditions and lifestyle factors. Secondary infertility may require fertility treatments such as In Vitro Fertilisation (IVF) or ICSI (Intra-Cytoplasmic Sperm Injection) to achieve a successful pregnancy.

Sperm straws are the containers that sperm is stored in after donation and potential lab processing. Sperm straws are small plastic tubes that are sealed before they are stored in liquid nitrogen. One sperm straw is enough for one round of fertility treatment (regardless of the type of fertility treatment).

Unwashed sperm is the same as an ejaculate, meaning that unwashed sperm contains ejaculate fluid and cells. The only lab processes performed on unwashed sperm is the addition of a cryoprotective fluid, the filling of the sperm into straws and the freezing.

Unwashed sperm can be used for ICI treatments, but should not be used for IUI treatments as the injection of unwashed sperm into the uterus can cause a severe allergic reaction.


Washed sperm is sperm that has been processed in a lab after donation. Prior to cryopreservation, the motile sperm cells are separated from the seminal fluid. One method of doing this is by using a so-called density gradient centrifugation. The sperm cells are then washed - that is, the gradient is removed from the sperm cells - and a cryopreservative fluid is added.

Washed sperm is IUI-ready, meaning that the sperm does not need further processing before being it can be used for insemination.

In cases of X-linked dominant inherited conditions, only one mutated copy of a gene is necessary to cause disease. In such cases, disease will be passed from a mother to both her sons and daughters whereas the father can only pass on the disease to his daughter (because males do not pass on an X chromosome to their sons). Parents will be affected by the condition themselves.

Rett syndrome and incontinentia pigmenti type 1 are examples of X-linked dominant inherited conditions.

X-linked disorders are caused by a mutated gene on a sex chromosome - unlike autosomal inherited conditions.

X-linked conditions primarily affect men or boys because they only have one X chromosome. Females have two.

Rett syndrome and incontinentia pigmenti type 1 are examples of X-linked dominant inherited conditions.