By (embryologist) and MD, FACOG, FACS, FACE (gynecologist).
Last Update: 06/06/2018

Surrogacy or surrogate motherhood is a type of assisted reproductive technology known as third-party assisted reproduction, along with egg and sperm donation. For surrogacy to be possible, Intrauterine Insemination (IUI) or In Vitro Fertilization (IVF) is necessary.

Additionally, other reproductive technologies like Preimplantation Genetic Diagnosis (PGD) or donor conception may be used in a process of surrogacy. Find the details of each in the following sections.

Fertility treatments

The most common assisted reproductive technologies, that is to say, those that allow childless couples to have children are Intrauterine Insemination (IUI) and In Vitro Fertilization (IVF). There exist two types of IVF at the same time: classical IVF and ICSI (Intracytoplasmic Sperm Injection).

Here’s some insight about each one of them:

Intrauterine insemination

It is a simple technique that consists in placing a sample of semen in the uterine cavity of the patient. The ultimate goal is that the sperm are able to reach the Fallopian tube and inseminate the egg that will give rise to an embryo. Then, the fertilized egg must reach the womb and attach to it. This process is known as embryo implantation and marks the start of a new pregnancy.

In order for the chances of success to be increased in comparison with natural insemination (intercourse), the sperm specimen goes through a process called sperm capacitation. This procedure improves the quality of the sample and activates sperm so that they are able to reach and penetrate the egg cell.

As a patient, the woman is given fertility drugs to control the moment of ovulation so that it occurs right before being inseminated, thereby increasing the chances for the sperm to hit the egg and fertilize it.

In vitro fertilization

IVF is more technically challenging than IUI because it involves the collection of eggs directly from the ovary via a process called follicle puncture or ovum pick-up (OPU). Once harvested, fertilization will occur in the lab. The resulting embryos are cultured for 3 to 5 days before being transferred back to the patient’s womb. Obviously, the ultimate goal is that she gets pregnant after the embryo transfer (ET).

There exist two types of IVF:

Classical or standard IVF
The eggs collected are put in culture along with a determined concentration of processed sperm, so that at least one of cell is able to reach the egg and fertilize it.
Sperm microinjection (ICSI)
A single sperm cell is selected and, using a microinjector, the specialist injects it manually into the egg cell.

Additional techniques

Along with the basic techniques already explained above, there exist other reproductive technologies that can be used as complementary techniques in case they are necessary. The following are the most common ones:

Egg & sperm donation

Both in cases of IUI, IVF, and ICSI, using donor sperm is a viable option.

However, if you need donor eggs, IUI is not possible. In those cases where DE are required, only IVF or IVF/ICSI is possible.

A person or couple may turn to donor conception (egg and/or sperm donation) for the following reasons:

  • Absence of own eggs and/or sperm
  • Poor quality
  • Presence of genetic diseases likely to be transmitted to offspring

Preimplantation Genetic Diagnosis (PGD)

PGD is a technique used for the genetic screening of embryos before they are transferred in order to prevent the transmission of genetic diseases or abnormalities to children.

With PGD, a cell or set of cells is removed from the embryo (biopsy) to examine them genetically and find out whether it has some kind of genetic disease or abnormality. Only healthy embryos will be placed into the woman’s uterus, that is, embryos that are free from genetic diseases that could affect the baby-to-be.

PGD is an option that is available only in IVF and IVF/ICSI procedures.

Cryopreservation of gametes & embryos

Cryopreservation of eggs, sperm and embryos is an option that allows men and women to retain their fertility and optimize the outcomes of fertility treatments.

In the case of egg and embryo cryopreservation, the method used is called vitrification, an ultrarrapid freezing system thanks to which consistently high success rates can be reached.

Techniques used in surrogacy

Surrogacy is a fertility treatment whereby a woman offers to carry someone else’s child.

We can differentiate two types of surrogacy based on the technique used to achieve the pregnancy of the surrogate:

Traditional or partial surrogacy
IUI is the technique used in this type of surrogacy. The surrogate is inseminated artificially with sperm from the intended father or a donor. This means that she will be the genetic and birth mother of the resulting child.
Gestational or full surrogacy
IVF or IVF/ICSI is used to get the surrogate pregnant. In this case, she is known as gestational surrogate or gestational carrier, because she is just the birth mother of the child, with no genetic link to him or her.

Today, traditional surrogacy has fallen into disuse, because the fact that the surrogate is genetically linked to the child, which is to say, she is the biological mother, carries more risks than gestational surrogacy.

The most common method used today is IVF, since it allows for the intended mother to be the genetic mother of the baby in spite of not being able to carry the pregnancy. Read more: What Is IVF Surrogacy? – Process, Success Rates & Cost.

Should the intended mother be unable to use her own oocytes, the embryo will be created using the eggs of a donor, who cannot be the same person as the gestational carrier. As one shall see, the ultimate goal is to prevent the creation of a genetic link between the GC and the resulting child.

Embryo cryopreservation is common in surrogacy arrangements as well. If the GC doesn’t get pregnant on the first attempt, a Frozen Embryo Transfer (FET) will be performed in subsequent cycles using these unused embryos instead of starting a complete cycle anew.

Furthermore, surrogacy and PGD are compatible as well. In the United States, PGD is commonly performed in cases of surrogacy, and it can be used to choose the sex of the resulting child as well, should the IPs wish so. PGD is a costly technique that is rarely used when no genetic disease is present in the gametes used to create embryos, though.

Surrogacy is probably the most confusing of all infertility treatments. Transparency is a key value for us when it comes to recommending a clinic or agency for intended parents. You can now use this tool to receive a detailed report that will solve any question you may have, and most importantly, to help you avoid potential frauds.

FAQs from users

Can a woman carry another woman’s egg?

By Andrea Rodrigo (embryologist).

Yes. In fact, that’s a short definition for IVF surrogacy or gestational surrogacy: the egg of the intended mother or a donor is used to create the embryos that will be carried by the surrogate.

Recommended for you: What Is Surrogacy & How Does It Work? – Everything You Should Know.

During endometrial preparation, is it better to do the natural cycle or the substituted cycle?

By Mark P. Trolice MD, FACOG, FACS, FACE (gynecologist).

In cycles with frozen embryos, pregnancy rates per embryo transfer are the same whether the cycle is natural or substituted (with medication). No medication is needed for a natural cycle, which reduces the cost of treatment. However, setting a precise transfer date is more complicated than a substituted cycle.

How is IVF surrogacy done?

By Andrea Rodrigo (embryologist).

Broadly speaking, from the technical viewpoint, it works like a classical IVF. First, egg retrieval; second, fertilization in the lab; third, embryo culture; and fourth, embryo transfer.

However, the difference lies in the fourth step: the resulting embryos are not transferred back to the intended mother’s uterus, but to the womb of the gestational surrogate.

What are the success rates of IVF using a gestational carrier?

By Andrea Rodrigo (embryologist).

An ongoing pregnancy is achieved in 75 percent of surrogacy arrangements on average. Once the surrogate mother is pregnant, the live birth rates are as high as 95%.

Can a surrogate mother get pregnant via natural insemination?

By Andrea Rodrigo (embryologist).

This alternative option is totally unadvisable and highly dangerous. First, because a surrogacy contract that is properly reviewed by an attorney should be present. Second, because it means that the surrogate is genetically linked to the child, with the subsequent risks associated. In fact, it cannot be considered a type of surrogacy arrangement.

Suggested for you

As one shall see, the most common type of reproductive technology used in surrogacy arrangements is IVF. To get more information about the details, check this out: What Is IVF Surrogacy? – Process, Success Rates & Cost.

Surrogacy may be recommended for a number of medical reasons, including infertility issues. Click here to read more: Infertility & Surrogacy – What Are the Medical Reasons for Surrogacy?

Finally, if you liked this information, you may want to go through this: What Are the Different Types of Surrogacy? – Names & Definition.

Our editors have made great efforts to create this content for you. By sharing this post, you are helping us to keep ourselves motivated to work even harder.

Authors and contributors

 Andrea Rodrigo
Andrea Rodrigo
Embryologist
Bachelor's Degree in Biotechnology from the Polytechnic University of Valencia. Master's Degree in Biotechnology of Human Assisted Reproduction from the University of Valencia along with the Valencian Infertility Institute (IVI). Postgraduate course in Medical Genetics. More information about Andrea Rodrigo
 Mark P. Trolice
Mark P. Trolice
MD, FACOG, FACS, FACE
Gynecologist
Mark P. Trolice, M.D., FACOG, FACS, FACE is Director of Fertility CARE – The IVF Center and Clinical Associate Professor in the Department of Obstetrics & Gynecology (OB/GYN) at the University of Central Florida College of Medicine. He is Board-certified in REI and OB/GYN, and maintains annual recertification. His colleagues select him as Top Doctor in America® annually, one among the top 5% of doctors in the U.S. More information about Mark P. Trolice
Florida license: ME 78893

Find the latest news on assisted reproduction in our channels.