Sperm washing is the process in which individual

sperms Sperm is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm with a tail known as a flagellum, whi ...

are separated from the

semen Semen, also known as seminal fluid, is an organic bodily fluid created to contain spermatozoa. It is secreted by the gonads (sexual glands) and other sexual organs of male or hermaphroditic animals and can fertilize the female ovum. Semen i ...

. Washed sperm is used in

artificial insemination Artificial insemination is the deliberate introduction of sperm into a female's cervix or uterine cavity for the purpose of achieving a pregnancy through in vivo fertilization by means other than sexual intercourse. It is a fertility treatme ...

using the

intrauterine insemination Artificial insemination is the deliberate introduction of sperm into a female's cervix or uterine cavity for the purpose of achieving a pregnancy through in vivo fertilization by means other than sexual intercourse. It is a fertility treatm ...

(IUI) technique and in

in vitro fertilization In vitro fertilisation (IVF) is a process of fertilisation where an egg is combined with sperm in vitro ("in glass"). The process involves monitoring and stimulating an individual's ovulatory process, removing an ovum or ova (egg or eggs) ...

(IVF). It may also be used to decrease the risk of

HIV The human immunodeficiency viruses (HIV) are two species of ''Lentivirus'' (a subgroup of retrovirus) that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the immune ...

transmission by an HIV-positive male, in which case the washed sperm is injected into a female using an artificial insemination technique. Sperm washing involves removing any mucus and non-motile sperm in the semen to improve the chances of fertilization and to extract certain disease-carrying material in the semen. Sperm washing is a standard procedure in

infertility treatment Assisted reproductive technology (ART) includes medical procedures used primarily to address infertility. This subject involves procedures such as in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), cryopreservation of gametes o ...

. Once the fastest sperm have been isolated, before using them for artificial insemination or ''in vitro'' fertilization, it is important to confirm the absence of HIV virus in the sample. The sample obtained after washing is analysed, usually using the PCR technique, to check that there is no viral particle. If the result is negative, i.e. there is no virus, this sample is suitable for use in assisted reproduction treatments. These samples are usually free of the virus in a high percentage.

Procedure

Sperm washing takes place in a laboratory following

sperm donation Sperm donation is the provision by a man of his sperm with the intention that it be used in the artificial insemination or other 'fertility treatment' of a woman or women who are not his sexual partners in order that they may become pregnant by hi ...

. Sperm may be washed by

density gradient centrifugation In biochemistry and cell biology, differential centrifugation (also known as differential velocity centrifugation) is a common procedure used to separate organelles and other sub-cellular particles based on their sedimentation rate. Although o ...

or by a "''direct swim-up''" technique that does not involve centrifugation. In normal semen samples, centrifugation causes no more DNA damage to

spermatozoa A spermatozoon (; also spelled spermatozoön; ; ) is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote. (A zygote is a single cell, with a complete set of chromosomes, ...

than a direct swim-up technique. Washed sperm is concentrated in Hams F10 media without

L-glutamine Glutamine (symbol Gln or Q) is an α-amino acid that is used in the biosynthesis of proteins. Its side chain is similar to that of glutamic acid, except the carboxylic acid group is replaced by an amide. It is classified as a charge-neutral, ...

, warmed to . A chemical known as a

cryoprotectant A cryoprotectant is a substance used to protect biological tissue from freezing damage (i.e. that due to ice formation). Arctic and Antarctic insects, fish and amphibians create cryoprotectants (antifreeze, antifreeze compounds and antifreeze prot ...

is added to the sperm to aid the freezing and thawing process. Further chemicals may be added which separate the most active sperm in the sample, as well as extend or dilute the sample so that vials for a number of inseminations are produced.

Decreased HIV transmission

Sperm washing can be used to decrease the risk of HIV transmission in HIV-positive males, because the infection is carried by the seminal fluid rather than the sperm. One Italian study from 2005 of 567

serodiscordant A serodiscordant relationship, also known as mixed-status, is one where one partner is infected by HIV and the other is not. This contrasts with seroconcordant relationships, in which both partners are of the same HIV status. Serodiscordancy contri ...

couples treated with washed sperm resulted in no horizontal (to the woman) or vertical (to the child) HIV

seroconversion In immunology, seroconversion is the development of specific antibodies in the blood serum as a result of infection or immunization, including vaccination. During infection or immunization, antigens enter the blood, and the adaptive immune system ...

.About.com > HIV and Sperm Washing.
By Mark Cichocki, R.N. Updated December 18, 2009 However, there is no 100% guarantee that washed sperm is free from the virus.

History

Sperm washing was first used in

Milan Milan ( , , Lombard: ; it, Milano ) is a city in northern Italy, capital of Lombardy, and the second-most populous city proper in Italy after Rome. The city proper has a population of about 1.4 million, while its metropolitan city h ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...

. The oldest child conceived using this method was born in 1997 and is HIV negative. The first known baby conceived this way in the United States, Baby Ryan, was born in 1999 through the

Special Program of Assisted Reproduction The Special Program of Assisted Reproduction (SPAR) is a program offered to HIV discordant couples (serodiscordant) at the Bedford Research Foundation's clinical laboratory. The program takes advantage of ART ( assisted reproduction technology) pro ...

started by

Ann Kiessling Ann A. Kiessling is an American reproductive biologist and a researcher in human parthenogenic stem cell research at The Bedford Research Foundation. She was an associate professor in teaching hospitals of Harvard Medical School (Brigham and Wome ...

. Starting in the mid-1990s the technique was used to help HIV discordant couples conceive without passing the virus from the father to the mother or child. The idea is that when the male is HIV positive, the technique will reduce the risk of transmission to the female. For years there were lingering doubts about the safety of the procedure, and many couples had to travel to places that would do the procedure, such as Italy. Today, hundreds of babies have been born through this process.

References

External links

Special Program of Assisted Reproduction at the Bedford Research Foundation Clinical Laboratory

Bedford Research Foundation
{{DEFAULTSORT:Sperm Washing Prevention of HIV/AIDS Artificial insemination Fertility medicine