Surrogacy 101: A guide to all the terms you need to know

Eran Amir

CEO and Founder of GoStork

Surrogacy is a beautiful, yet complicated process with plenty of administrative, medical, and legal terms. As an intended parent or prospective gestational carrier, it’s easy to get overwhelmed when faced with confusing technical language and not much support interpreting it. With this in mind, we’ve created a comprehensive list of the common terms you will come across in your surrogacy journey.

First things first: let’s review the basics.

What is surrogacy?

To understand surrogacy, it helps to first take a look at where it fits in the journey to having a baby. Let’s start from the very beginning.

Third party reproduction

The American Society for Reproductive Medicine describes this as the involvement, in the reproductive process, of someone other than the individual or couple who will raise the child. This includes pregnancy through donated eggs, sperm, or embryos, as well as gestational-carrier arrangements where the pregnancy is carried by someone other than the parents who will raise the child. For the purposes of this article, we’ll explore gestational-carrier arrangements, widely known as surrogacy.

In Vitro Fertilization (IVF)

IVF involves the combination of an egg with sperm in a laboratory setting. There are five main steps to this procedure: 

  1. Stimulation (to boost egg production)
  2. Egg retrieval
  3. Insemination and fertilization
  4. Embryo culture (monitoring of the embryo to ensure its growing well – procedures that check for genetic disorders can be offered at this stage)
  5. Embryo transfer


Surrogacy is a method of assisted reproductive technology where a woman (known as a ‘surrogate’ or ‘gestational carrier’) carries a pregnancy for an individual or a couple. There are various types of surrogacy arrangements:

Traditional Surrogacy / Surrogate Pregnancy

With this type of surrogacy, the woman who becomes pregnant also provides the egg, meaning that the baby has a genetic link to the surrogate. This is becoming less common due to the legal and emotional complexities involved. Traditional surrogacy requires the termination of parental rights. Once these rights are terminated, the genetically unrelated intended parent will have to complete a stepparent adoption. In some states, traditional surrogacy is illegal even if gestational surrogacy is allowed. 

Gestational Surrogacy / Gestational Pregnancy

Through this process, the gestational carrier is a woman who carries a pregnancy from an embryo created by the intended parents, either through their own egg and sperm or through donations. Unlike in traditional surrogacy, the gestational carrier has no genetic link to the baby. While this process requires in vitro fertilization (IVF), it is still more common in the US than traditional surrogacy.

In short then, a woman who carries a baby in a traditional surrogacy arrangement is known as a surrogate mother; in a gestational pregnancy, the woman is known as a gestational carrier. That said, you will often find both terms used interchangeably but it certainly helps to know the difference as you research your journey.

Surrogacy arrangements are further distinguished by other criteria:

Commercial Surrogacy

This is when the gestational carrier is financially compensated for her role, beyond the reimbursement of medical expenses.

Altruistic Surrogacy

An altruistic carrier volunteers to carry a pregnancy, most often for family members or close friends, and is not financially compensated beyond her medical costs being covered.

Agency surrogacy

When the surrogacy journey takes place via an agency, it’s called an agency surrogacy. Agencies assist by providing expertise and support throughout the process.

 Independent surrogacy

Also known as private surrogacy, the independent surrogacy process does not include the services of a surrogacy agency. In this case, only a lawyer and a fertility clinic are necessary at different points in the process.

Identified surrogacy

Working with a surrogate or gestational carrier one knows in advance is called ‘identified surrogacy’. There are many benefits to identified surrogacy: potentially less expensive, stronger sense of trust, and easier to stay in touch.  That said, there are other factors to take into consideration, including the possibility of financial disputes with someone important in your life, difficult feelings, and a source of stress on family relationships.

Assisted Reproductive Technology (ART)

ART is the term used to describe medical infertility procedures, such as IVF (see below), in which the fertilization of oocytes (eggs) occurs in a laboratory setting. The Centers for Disease Control and Prevention (CDC) define ART as fertility treatments in which both eggs and embryos are handled. ART procedures involve the surgical removal of eggs from a woman’s ovaries, combining them with sperm in the laboratory, and returning them to the woman’s body or donating them to someone else.

Who is involved in the surrogacy process?

Here are the individuals and agencies involved in the process: 

Intended parent(s)

The person or persons who become the legal parents of the child born through surrogacy and who will raise the child – often abbreviated to IPs.

Gestational carrier / Surrogate

A person who carries a pregnancy for someone else. 

Egg donor

A woman who donates her eggs or oocytes for use in fertility treatments. The egg donor can be the intended parent or anonymous.

Sperm donor

A man who donates his sperm for use in artificial insemination or other fertility treatments.

Fertility clinic

Fertility clinics are medical clinics that assist individuals and couples become parents, when pregnancy cannot otherwise be achieved. The fertility clinic is integral to the surrogacy process. The gestational carrier will have to be approved by a doctor at the fertility clinic before the process can start. Both the intended parents and the surrogate then work closely with the clinic to complete IVF and the embryo transfer. 

Surrogacy Agency

A surrogacy agency provides intended parents with all – or at least the majority of – services required throughout the surrogacy process. Agencies aim to make the process as straightforward and stress-free as possible so you can focus on what’s important: the excitement of building a family.

Surrogacy Attorney

Surrogacy attorneys are essential for ensuring that the rights of both the gestational carrier and the intended parents are protected. They help intended parents understand local surrogacy laws and regulations, ensure that the process is completed in a legal manner, finalize the surrogacy contract, and establish intended parents’ parental rights as early as possible (more on this is specified in the ‘surrogacy contract’ definition, below).

Local Monitoring Clinic

This clinic will monitor the donor and the gestational carrier, providing medical treatment during both the egg donation process and the surrogate’s pregnancy. The monitoring clinic is usually local to the gestational carrier.

Now let’s continue to the surrogacy process itself, in the order it most commonly occurs:

The surrogacy process – in chronological order


This part is exciting. Matching is the process of finding a gestational carrier or intended parent(s). The gestational carrier decides what kind of intended parents she’d like to work with and what type of relationship will be pursued once the child is born. 

Depending on the country’s surrogacy laws, as intended parents, you may have the option to either play a role in selecting the gestational carrier or to leave it all in the hands of the surrogacy agency. Eitherway, in the US, you can choose what your preferences are in terms of the surrogate’s age, her BMI, medical and pregnancy history, the lifestyle led, costs, her health insurance, and her location and support system. Decisions should also be made on the number of cycles you’d like to try, and a standpoint taken on multiple births and pregnancy reductions or terminations. Once decided, this information should be provided to the agency.

Once a match is made, the surrogate and intended parents get to know each other through contact mediated by the agency or attorney. You can read more about choosing a surrogate, here

Minnesota Multiphasic Personality Inventory (MMPI-2)

The MMPI-2 is a clinical assessment tool used by mental health professionals to diagnose mental health disorders. Donors, surrogates, and intended parents may be asked to take this test as part of the screening process. In some states, a psychological evaluation by a licensed mental health professional is a legal requirement.

Personality Assessment Inventory (PAI)

This test assesses adult psychopathology. Donors, surrogates, and intended parents may be asked to take this test or the MMPI-2 as part of the screening process.

Hysterosalpingogram (HSG) or Sonohysterogram

Both are procedures that evaluate the inside of the uterus, with a focus on whether or not the fallopian tubes are open, ensuring that the gestational carrier can carry a pregnancy. These exams are part of a complete medical screening that prospective surrogates are required to undergo.

Surrogacy Contract

Also known as a Carrier Agreement or Surrogate Mother Contract, this legal document sets out the rights and obligations of both the woman carrying the pregnancy and the intended parents. The contract also outlines the parentage to be assigned to the baby once born, with clear clauses that the surrogate agrees to terminate her parental rights, and that custody will be relinquished to the intended parents as soon as possible after birth. Once both parties agree, the contract is signed.

Gestational Carrier Cycle Schedule

Once contracts are signed, a nurse at the IVF clinic coordinates with the gestational carrier to plan all the dates of the treatment cycle leading to the embryo transfer. The process includes an evaluation cycle, where each part of the cycle is duplicated as a ‘trial’ before the actual embryo transfer. Once the response of the uterus to hormonal stimulation is known, cycle synchronization can take place. This is where the menstrual cycles of the surrogate and the intended parent or egg donor are synchronized to maximize the chances of pregnancy, if using fresh eggs.

Egg retrieval

The egg donor or intended mother will undergo the egg retrieval procedure. A combination of hormonal medications is given to stimulate the development of multiple eggs within the ovary which are then retrieved. 

Embryo Gender Selection

A technique used by intended parents to choose the sex of their baby, either to better balance out their family or to avoid gender-specific disorders. Gender selection is performed through sperm separation or genetic testing with the embryo(s) of the preferred gender then transferred into the surrogate’s uterus.


A blastocyst is an embryo that has developed for five to seven days after fertilization and has two distinct cell types and a central cavity filled with fluid (blastocoel cavity). This is the stage that precedes implantation into the uterus.

Preimplantation Genetic Testing for Aneuploidies (PGT-A)

Previously known as preimplantation genetic screening (PGS), PGT-A provides information on the embryo’s genetic health, specifically the number of chromosomes, to help select the best embryo for transfer and improve the chances of a successful pregnancy.

Preimplantation Genetic Testing for Monogenic disorders (PGT-M)

Formerly known as preimplantation genetic diagnosis (PGD), PGT-M tests for inherited disorders caused by mutations in a single gene, such as cystic fibrosis or Huntington’s disease.

Embryo Transfer

Once the egg fertilizes and begins cell division, the resulting embryo is transferred into the gestational carrier’s uterus. A fertilized egg cell begins cell division after approximately 30 hours. Cell division is monitored to check which embryos are healthiest and most likely to lead to a successful pregnancy. Once this is determined, embryo transfer takes place between day three and five. The embryo transfer is the last part of the IVF process.

Fresh Embryo Transfer

For a fresh embryo transfer, the egg donor takes hormones to stimulate egg production. The eggs are retrieved and fertilized, then the embryo is transferred to the surrogate. IVF experts disagree about whether fresh embryos offer better success rates than frozen ones. Studies show there is no one-size-fits-all solution as it greatly depends on factors such as age and number of eggs produced. 

Frozen Embryo Transfer

In this process, frozen embryos from a previous IVF or donor egg cycle are thawed and transferred into the uterus. Thanks to advances in technology, frozen embryo transfers have comparable success rates to fresh embryo transfers.

Single Embryo Transfer (SET)

One embryo is selected and placed directly in the uterus or fallopian tube. This single embryo can be frozen or chosen from a fresh cycle with multiple embryos. The remaining embryos can be stored for later use. SET lowers the chances of a multiple pregnancy (a pregnancy with more than one fetus). Several factors must be considered when deciding on SET, or otherwise. These include age, number of previous IVF cycles, and the quality of the embryos, among others. The CDC notes that for women who are good SET candidates, transferring one fresh embryo followed by one frozen embryo (if a second transfer is needed), offers the best chance of having one baby without increasing the chance for twins.

Multiple Embryo Transfer

In a multiple embryo transfer, two or more embryos are transferred during an IVF cycle. While this helps improve the chances of a successful pregnancy, it also increases the possibility of a multiple pregnancy (twins or more). It should be noted that the risk of premature birth and low birth rate increases with multiple births.

Beta Testing

The gestational carrier undergoes a blood test to check if she’s pregnant or not. This is typically done 10 days following the embryo transfer.

Chorionic Villus Sampling (CVS)

A test carried out as early as week 10 of pregnancy, to check for chromosomal conditions such as Down syndrome and other genetic conditions, such as cystic fibrosis. In this case, a catheter is inserted into the uterus to obtain a sample of cells from the placenta. 


This test is carried out between the 15th and 20th weeks of pregnancy – it checks for genetic or chromosomal conditions through a study of the cells in the amniotic fluid.

Pre-Birth Order and Post-Birth Order

A pre-birth order assigns parentage to the intended parents and removes any rights or obligations from the gestational carrier. Although a pre-birth order is not possible in all states, in those where it is, a legal document assigning parentage can be started in the fourth month of pregnancy and signed by the seventh. While a pre-birth order is issued prior to the birth, it is not effective until the child is born. In states where this is not possible, intended parents are seen in court within three to five days following birth, where a post-birth order is acquired. If a birth order is not in place by the time of birth, other guardianship documents protect the parties.

Click here for a list of surrogacy laws by state.

The surrogacy journey, simplified

Again, it’s easy to feel overwhelmed when faced with all the technicalities involved in surrogacy. However, a good understanding of the key terms you’ll encounter and what the process entails can help ensure a smoother journey.

At GoStork, we know how stressful the start of the surrogacy process can be. That’s why we’ve simplified the search with our first-of-its-kind platform. We provide comprehensive information about top US surrogacy agencies. Each agency’s profile includes clear cost breakdowns, prior customers’ ratings and reviews, a list of the services they offer, and much more background information. You can filter by personal preferences, then compare your favorites side-by-side, point-by-point using our unique comparison tool. What’s more, our platform is completely free to use! Find your ideal surrogacy agency, here.