Surrogate is a general term that refers to a woman who carries a pregnancy for another person. The commissioning person or couple who is trying to have a baby with a surrogate's help is known as the intended parent or parents. While the surrogate carries the pregnancy and gives birth, the intended parents raise the child and are listed on the birth certificate as the actual parents.
Here are more specific terms to address different surrogacy situations.
Traditional Surrogate Definition
A traditional surrogate is someone who is genetically related to the child she is carrying. Usually, a male intended parent provides a semen sample, which is cleaned and prepared by a fertility clinic, who then does an insemination procedure. In other cases, a sperm donor is used.
A traditional surrogate may also be called a partial surrogate, traditional surrogate mother, natural surrogate or just surrogate. The procedure is also sometimes known as straight surrogacy.
Due to legal complications (with the surrogate being both genetically related to the child and giving birth to the child), traditional surrogacy is not used or recommended as often as gestational surrogacy.
Gestational Surrogate Definition
A gestational surrogate (or gestational carrier) is not genetically related to the child she carries. Gestational surrogacy is also called IVF surrogacy, host surrogacy or full surrogacy.
In gestational surrogacy, the egg and sperm are usually taken from the intended parents, as in an IVF procedure, and any resulting embryo is transferred to the gestational surrogate. Other possibilities include the use of an egg donor with an intended male parent's sperm, an egg donor with a sperm donor or an embryo donation.
In some states and countries, a surrogacy arrangement can only take place if the baby is genetically related to at least one of the intended parents. In other places, this is not a problem.
Commercial Surrogate Definition
The term commercial surrogacy refers to an arrangement where the surrogate receives financial compensation above and beyond expenses. This is a legal arrangement in some states and countries.
In some places, commercial surrogacy is illegal. The intended parents may pay for medical costs, legal costs, lost work or other "reasonable expenses," but they cannot pay the surrogate purely for her role as a surrogate.
There are also places where any form of surrogacy is illegal, and contracts declaring the intended parents as the true parents are not recognized, valid or enforceable.
Surrogacy contracts may not be enforceable even in states or countries where surrogacy is technically legal, while other states and countries do enforce surrogacy contracts.
Due to the complexity of surrogacy arrangements, getting legal advice and consulting with an experienced psychologist about surrogacy is very important. Also, doing as much up-front research on surrogacy and other family-building options is essential to avoid potential problems or costly (emotional or financial) mistakes.
More about surrogacy:
Brinsden, Peter R. "Gestational surrogacy." Human Reproduction Update, Vol.9, No.5 pp. 483±491, 2003 http://humupd.oxfordjournals.org/content/9/5/483.full.pdf
Brisman, Melissa B. What to Consider when Considering Gestational Surrogacy. The InterNational Council on Infertility Information Dissemination. Accessed August 29, 2011. http://www.inciid.org/article.php?cat=thirdparty&id=786
Sharon LaMothe. http://lamothesurrogacyconsulting.com/ Email Correspondence/Interview. August 16 and 17, 2011.
Surrogacy. Human Fertilisation and Embryology Authority. Accessed August 29, 2011. http://www.hfea.gov.uk/fertility-treatment-options-surrogacy.html
Third Party Reproduction (Sperm, egg, and embryo donation and surrogacy). American Society of Reproductive Medicine. Accessed August 29, 2011. http://www.asrm.org/uploadedFiles/ASRM_Content/Resources/Patient_Resources/Fact_Sheets_and_Info_Booklets/thirdparty.pdf