A sperm bank, semen bank or cryobank is a facility that collects and stores human sperm mainly from sperm donors, primarily for the purpose of achieving pregnancies through third party reproduction, notably by artificial insemination. Sperm donated in this way is known as donor sperm.
The sperm is stored in small vials or straws of holding between 0.4 and 1.0 ml and cryogenically preserved in liquid nitrogen tanks. It has been proposed that there should be an upper limit on how long frozen sperm can be stored, however a baby has been conceived in the UK using sperm frozen for 21 years[1]. Before freezing, sperm may be prepared so that it can be used for intra-cervical insemination (ICI), intrauterine insemination (IUI) or for IVF (or assisted reproduction) (ART).
Sperm supplied by a sperm bank may be used where a woman’s partner is infertile or where he carries genetic disease. Increasingly, donor sperm is used to achieve a pregnancy where a woman has no male partner, including among lesbian and bisexual mothers-to-be. Sperm from a sperm donor may also be used in surrogacy arrangements and for creating embryos for embryo donation. Donor sperm may be supplied by the sperm bank directly to the recipient to enable a woman to perform her own artificial insemination which can be carried out using a needle-less syringe or a cervical cap conception device. The cervical cap conception device allows the donor semen to be held in place close to the cervix for between six to eight hours to allow fertilization to take place. Alternatively, donor sperm can be supplied by a sperm bank through a registered medical practitioner who will perform an appropriate method of insemination or IVF treatment using the donor sperm in order for the woman to become pregnant.
From a medical perspective, a pregnancy achieved using donor sperm is no different from a pregnancy achieved using partner sperm, and it is also no different from a pregnancy achieved by sexual intercourse.
Sperm banks may supply other sperm banks or a fertility clinic with donor sperm to be used for achieving pregnancies. Sperm banks may also supply sperm for research or educational purposes.
In countries where sperm banks are allowed to operate, the sperm donor will not usually become the legal father of the children he produces as the result of the use of the sperm he donates, but he will be the ‘biological father’ of such children. In cases of surrogacy involving embryo donation, a form of ‘gestational surrogacy’, the ‘commissioning mother’ or the ‘commissioning parents’ will not be biologically related to the child and may need to go through an adoption procedure.
As with other forms of third party reproduction, the use of donor sperm from a sperm bank gives rise to a number of moral, legal and ethical issues.
Men may also use a sperm bank to store their own sperm for future use particularly where they anticipate traveling to a war zone or having to undergo chemotherapy which might damage the testes.
Sperm banks make information available about the sperm donors whose donations they hold in the sperm bank to enable customers to select the donor whose sperm they wish to use. This information is often available by way of an on-line catalog. A sperm bank will also usually have facilities to help customers to make their choice and they will be able to advise on the suitability of donors for individual donors and their partners.
Where the recipient woman has a partner she may prefer to use sperm from a donor whose physical features are similar to those of her partner. In many cases, the choice of a donor with the correct blood group will be paramount with particular considerations involving the use of sperm from donors with negative blood groups. If a surrogate is used, for cases where the customer is not intending to carry the child, considerations about her blood group etc. will also be taken into account. Information made available by a sperm bank will usually include the race, height, weight, blood group, health and eye colour of the donor. Sometimes information about his age, family history and educational achievements will also asked to be shared. Some sperm banks make a ‘personal profile’ of a donor available and occasionally more information may be purchased about a donor, either in the form of a DVD or in written form. Catalogs usually state whether samples supplied in respect of a particular donor have already given rise to pregnancies, but this is not necessarily a guide to the fecundity of the sperm since a donor may not have been in the program long enough for any pregnancies to have been recorded.
If a woman intends to have more than one child, she may wish to have the additional child or children by the same donor. Sperm banks will usually advise whether sufficient stocks of sperm are available from a particular donor for subsequent pregnancies, and they normally have facilities available so that the woman may purchase and store additional vials from that donor on payment of an appropriate fee. These will be stored until required for subsequent pregnancies or they may be sold if they become surplus to the woman’s requirements.
The catalogue will also state whether samples of sperm are available for Intracervical Insemination ICI, IUI Intrauterine Insemination)or IVF use. ICI is for vaginal or cervical insemination and IUI are ‘washed’ samples prepared for intrauterine insemination where sperm is injected directly into the uterus. IVF treatment refers to ‘in vitro’ use, i.e. where fertilisation takes place outside the body, literally ‘in glass’, and therefore to treatments involving donor sperm where an egg is removed from the body and an embryo is created which is then re-inserted, or inserted, into a woman. The preparation for IUI is normally done by a gradient centrifugation where prostaglandins and bacteria is removed from the plasma. Sperm prepared for [IVF] use normally contains a smaller sample of highly concentrated sperm.