Surrogacy involves using one woman's uterus for the purpose of implanting and carrying an embryo in order to deliver a baby for another person or couple. The woman who will carry the embryo is known as the surrogate.
This process entails using in vitro fertilization in order to place the fertilized egg into the surrogate's uterus. There are two primary types of surrogacy. These are traditional and gestational, and each works in a somewhat different fashion.
When using traditional surrogacy, the surrogate acts as both the egg donor and as the actual surrogate for the embryo, and she is impregnated using a process known as intrauterine insemination, or IUI.
In this IUI procedure, the doctor will transfer sperm that is taken from the biological father and will subsequently transfer that sperm into the surrogate's uterus so that fertilization may take place naturally.
Therefore, with traditional surrogacy, the surrogate is also the biological mother of the child. This type of surrogacy is typically only used if the biological mother's egg and/or the biological father's sperm are unable to be used.
With gestational surrogacy, the surrogate's eggs are not used at all. Therefore, the child will not be related to the surrogate biologically. Using the gestational type of surrogacy, the embryo is actually created by using both the biological father's sperm and the biological mother's egg through a process called in vitro fertilization.
It is not until after the biological mother's egg is fertilized that the embryo is transferred to the uterus of the surrogate using the process of in vitro fertilization. In most cases, it will take between three and five days for the embryos to develop in the laboratory prior to transferring them to the surrogate. Then, once the embryo has successfully been placed into the surrogate's uterus, the surrogate will carry the embryo through the pregnancy term until its birth.
The rate of success when using in vitro fertilization will depend upon several factors such as the age and health of the biological mother who is providing the eggs. Interestingly, however, in many cases, the rates of pregnancy are actually higher when using eggs that are taken from biological mothers who are otherwise infertile versus when eggs are taken from fertile women.
Even though traditional and gestational surrogacy are very different, both are typically just as safe as going through a traditional biological pregnancy. Prior to starting the surrogacy process, the surrogate is first screened in order to determine her overall health. If she is not deemed healthy enough to carry the embryo, another surrogate must be chosen. Once ready to proceed, if using gestational surrogacy, the surrogate will be required to take certain medications that will assist her in developing numerous eggs for use in the fertilization process. When the baby is ready for birth, the surrogate will go through the typical process for delivery of the baby. After the baby's birth, he or she will then go home with the new parents.