How Does a Surrogate Mother Get Pregnant?

pregnant woman holding flowers

Becoming a surrogate mother is a big decision. It's a decision that is carefully made by women who fit a number of requirements and are compelled to carry a baby for intended parents who are unable to do so themselves. One of the main questions many women come across when considering becoming a surrogate, is: How do surrogates get pregnant?

The simple answer: Through In vitro fertilization (IVF).

But a more detailed answer can be found within this blog. Here’s the complete breakdown of the process for becoming pregnant as a gestational carrier.


In Vitro Fertilization

In vitro fertilization, commonly referred to as IVF, is a reproductive technology procedure in which a female's egg is fertilized by a sperm outside of the body.

What is IVF?

IVF takes place in a laboratory and is done by a qualified professional. The technique of IVF begins with careful attention to a woman's ovulatory cycle, followed by extracting an egg from her ovaries, and then integrating the intended father's sperm with her egg in the appropriate labware. After the process is complete, the embryo is preserved and monitored until it is time to be transferred to the surrogate's womb.

How does In Vitro Fertilization Work?

When it comes to whose eggs are used for IVF, this process varies depending on the type of surrogacy being used in the given situation. Traditional surrogacy and gestational surrogacy are quite different, and here's how.

Traditional Surrogacy

In traditional surrogacy, the surrogate mother's eggs are used in combination with the intended father's sperm. In traditional surrogacy, the surrogate mother is the biological mother of the child. Traditional surrogacy is not considered to be a

n ethical practice in many states, and most IVF clinics choose not to use this option for fertility.

Gestational Surrogacy

In gestational surrogacy, the surrogate is not genetically related to the child. The sperm and the egg are transferred from both intended parents (or from another non-related source, like egg and/or sperm donors) to begin the IVF process in the lab. Once both the embryo and gestational surrogate are ready, the transfer process occurs, impregnating the gestational carrier with the intended parents' baby.

Preparing for embryo transfer doctor meeting

Preparing for Embryo Transfer

After finding a trusted gestational surrogacy network, being matched with intended parents, and completing all necessary checks to become a gestational surrogate- it's time to prepare for the embryo transfer. Here's what a typical embryo transfer looks like here at Vermont Surrogacy Network.

Health Checks and Medications

It all begins with a baseline appointment, in which the surrogate undergoes an internal ultrasound that evaluates the lining of her uterus.

The gestational surrogate may have been prescribed medications (such as birth control pills or an injectable medication called Lupron) for a while, or she may be required to report with the first day of her period. Regardless of her medication protocol, she is required to have an ultrasound and blood test before beginning the embryo transfer medication to stimulate the growth of her uterine lining.

The goal of this initial ultrasound is to examine her lining to ensure that it is thin and appears as it should at the start of a menstrual cycle. Doctors will examine her ovaries to make sure that there isn't a follicle (a fluid-filled sac containing an egg) developing. This is done to ensure that the embryo will be transferred at the most optimal time for implantation.

The surrogate will also have her blood tested to check her estrogen and progesterone levels- two critical hormones during conception and pregnancy. These tests will determine whether or not the surrogate is at her "baseline", and give the doctors guidance on what steps she should take if abnormal levels are detected. At this stage, the laboratory will also likely draw repeat STI tests to ensure that the results are confirmed before the transfer.

Taking Estrogen

When all results are in and the doctor has decided that the surrogate's baseline ultrasound and lab tests are normal, estrogen therapy will begin.

Estrogen has two distinct effects in a transfer cycle. The first is that it stops the ovaries' activity so that no follicle develops and an egg isn't released. The second effect is that it thickens the uterine lining, which helps it prepare for a safe and effective embryo transfer to come.

Oral estrogen is the most popular option since it is the simplest and most affordable type, however, some practitioners prefer to use vaginal formulations, patches, or even injections.

Lining Checks

The next phase of preparing for embryo transfer is the scheduling for a lining check appointment once the surrogate has begun taking estrogen. Around 10-14 days after the start of estrogen treatment, the surrogate will have her next appointment. The lining check is very similar to the baseline appointment, with a few important differences.

The ovaries should still not be producing any activity with a follicle that would release an egg at this point. The uterine lining should be thickened, according to most clinics, by at least 8mm. The result of the blood tests will normally indicate that the surrogate's estrogen levels are high, and the progesterone levels are low.

Though not likely, there is a chance of the test detecting an elevated progesterone level indicating that the surrogate has ovulated. This is possible to happen to some women taking estrogen, but this is not normally the case. The surrogate will then continue to take the prescribed estrogen until her doctor has advised otherwise.

Lining Check Results

The results of the lining check will determine a date for the embryo transfer to be tentatively scheduled. The surrogate is then given clear instruction on when to begin taking progesterone for an effective transfer. The best method to get the required progesterone for an embryo transfer cycle is by injection into the surrogate's muscle. These injections are given into her muscle at the same time each day, generally in the evening or later at night. The surrogate may feel uncomfortable while receiving them, but the clinic should be able to offer some guidance to make them more bearable.

Day of Embryo Transfer

The big day is finally here- embryo transfer day! Embryo transfers are typically scheduled to take place during the afternoon, to give the frozen embryo time to thaw fully to be ready for transfer. The gestational carrier is requested to come in with a completely full bladder, which will assist in the visualization of the uterus during the insertion. The embryo transfer itself takes just a few minutes and is actually rather simple.

During Embryo Transfer

In the procedure room, the surrogate may have a support person (or more than one, depending on the clinic) with her. Though not required, this is a fantastic way for the intended parents to feel involved in the process and help strengthen their relationship with one another by sharing the experience. Of course, this decision is always up to the gestational surrogate and intended parents.

When the surrogate is settled in the procedure room and her cervix has been disinfected, the doctor will carefully insert a thin plastic catheter into her uterus through her cervix. The catheter is connected to a syringe that contains the embryo, some fluid, and air to produce bubbles. An abdominal ultrasound is used to examine the uterus and catheter as they are inserted into the uterine lining's thickest part.

After ensuring that the catheter is positioned correctly, the provider will use the syringe to release the embryo into the uterus. The air bubbles from the syringe will be detected on the ultrasound at this time, as a way to show when the insertion is complete. The doctor then removes the catheter and sends it to the laboratory to confirm that the embryo was released.

Beyond Embryo Transfer

After the transfer is complete, surrogates are typically asked to lay down and rest at the clinic for up to an hour. After that, the procedure is complete and the waiting begins!

The gestational carrier must continue to take all of her prescription medicines until she gets her pregnancy test, which is generally done 10 days after the transfer. While doing an at-home pregnancy test may seem like a good idea, clinics usually do not recommend it. The blood test is significantly more reliable, and the high rate of inaccurate results from at-home tests can cause stress for the gestational carrier and intended parents.

After 10 days and an official pregnancy confirmation from the gestational surrogacy clinic, the gestational carrier is officially pregnant! This is a beautiful moment for all parties involved, and the next chapter of the journey has begun.

Work With a Trusted Surrogacy Network

Gestational surrogacy is an excellent option for many individuals who are unable to have children of their own. If you're looking for more information on how gestational surrogacy can work for your family, or considering becoming a surrogate yourself, or simply want to learn more about the surrogacy process, get in touch today.

We are here to help you through every step of the process, and look forward to meeting you!