Cryopreservation is the freezing of reproductive tissue – eggs, sperm or embryos – for later use with assisted reproductive technology (ART). There are a variety of reasons that cryopreservation may be done, both electively or as part of a course of infertility treatment. When performed as an elective service, cryopreservation is also commonly referred to as “fertility preservation.”

Midwest Fertility Specialists provides comprehensive cryopreservation services to help you grow your family now or in the future, including the retrieval, testing and storage of reproductive tissue. We will store your eggs, sperm or embryos indefinitely until you are ready to use them.

Below is more information on the three different types of cryopreservation we offer.

Cryopreservation of Eggs

Why Freeze Your Eggs?

You may cryopreserve your eggs for a variety of reasons, including:

  • The desire to delay having children, perhaps in pursuit of professional or educational aspirations or because you haven’t yet found a partner with whom you want to have children. Your eggs become less and less viable as you age, so having a reserve of your own younger, healthier eggs available can greatly improve your chances of success in getting pregnant with ART later.

  • To preserve your potential for a family after certain illnesses or medical procedures that can cause a loss of fertility, including certain types of cancer and cancer treatment, such as chemotherapy and radiation therapy.

  • As an alternative to freezing embryos for religious or ethical reasons.

  • Egg donation.

What is the Process for Freezing Eggs?

Egg freezing is a three-step process:

  1. You take fertility medications to help stimulate your ovaries to produce multiple eggs.

  2. Your eggs are retrieved from your ovaries during a minor, ultrasound-guided outpatient procedure. The short procedure is done with sedation, so you will need to have someone drive you home.

  3. After your eggs are retrieved, they are put into a protective solution and frozen in a specialized tank.

If and when you decide you are ready to use your eggs, they will be thawed and prepared for insemination (fertilization) for use in IVF.

Cryopreservation of Sperm

Why Freeze Your Sperm?

You may cryopreserve your sperm for a variety of reasons, including:

  • If sperm collection cannot be done simultaneously with egg retrieval to perform insemination during an IVF cycle.

  • To preserve your ability to have a family after certain illnesses or medical procedures, such as certain types of cancer and cancer treatment. Radiation therapy, chemotherapy and surgery can impact sperm and semen production and cause temporary or permanent loss of fertility.

  • When ejaculation is not possible due to erectile dysfunction or other medical conditions.

  • Sperm donation.

  • Preservation of sperm prior to gender reassignment.

What is the Process for Freezing Sperm?

If surgical retrieval of sperm is not required, a semen sample is preferably obtained by masturbation in one of our collection rooms. If you cannot collect a specimen via masturbation, then collection through sexual intercourse is an option. There are specially designed silastic condoms that can be worn during intercourse to collect a semen sample, which must be brought to our office within an hour of collection. Two to five days of abstinence (no ejaculation) is required prior to obtaining a semen sample.

We analyze your semen for characteristics like concentration, motility and morphology (how the sperm look), then it is frozen and stored in liquid nitrogen for future use with ART.

Cryopreservation of Embryos

Why Freeze Your Embryos?

An embryo is created when an egg is fertilized by a sperm in the lab. Like eggs and sperm individually, embryos can be frozen for use with ART in the future. Embryos are often frozen because more than one is created during a course of treatment, such as in vitro fertilization (IVF).

IVF has a better chance of success when more than one ovarian follicle and more than one egg develop during the treatment cycle. All available eggs are retrieved from your ovaries, and the best eggs are chosen for insemination in the lab.

The pregnancy rates following embryo transfer in an IVF cycle are directly related to the number and quality of embryos transferred. However, transfer of an excessive number of embryos significantly increases the chance of a multiple pregnancy (twins, triplets, etc.) and the associated obstetrical risks. Therefore, the number of embryos transferred must be limited, potentially leaving eggs or embryos left over.

There are two options for remaining eggs that are not used to create embryos for transfer — they may either be discarded without fertilization or inseminated and cryopreserved as embryos for later use.

Insemination of all extra eggs and cryopreservation of any resulting embryos offers several advantages:

  1. Cryopreserved embryos may be transferred during subsequent months without the need for additional surgery, thereby increasing the chances of conceiving as a result of any one surgical procedure.

  2. Cryopreserved embryos may be transferred in cycles during which minimal or no medication is used.

  3. Because embryos are more substantial, they may withstand the freezing process better than eggs.

What is the Process for Freezing Embryos?

The process for freezing embryos is very similar to freezing eggs, with the added step of joining the eggs with sperm, either from your partner or a donor, in the lab.

Embryos can be successfully frozen at several different developmental stages. The decision as to the optimal timing for freezing varies by lab and procedure. The following are Midwest Fertility’s guidelines:

  1. On the first day after egg retrieval, the eggs will be evaluated for signs of fertilization and for overall appearance.

  2. On day three, the embryos will again be evaluated by the lab. If your embryos are progressing according to the biologist’s criteria, they will continue to monitor your embryos through to the blastocyst stage (day five).

  3. If you are going through treatment, on day five, the highest quality embryos will be transferred, and any others that are still progressing will be cryopreserved on either day five or six.

We will keep you informed as to the status of your embryos.

Is Cryopreservation Effective?

It is never a guarantee that reproductive tissue will be viable when thawed. However, advances in egg and embryo freezing techniques over the past 10 years have improved the process of cryopreservation considerably. Midwest Fertility uses a process called vitrification, which greatly reduces the chance of ice formation within eggs and embryos and has significantly increased the likelihood of survival upon thawing. There is also extensive evidence that there is no increased risk of congenital birth defects, anomalies or other abnormalities in pregnancies achieved with cryopreserved eggs or embryos.

Similarly, there is no guarantee that frozen sperm will be of sufficient quantity or quality to result in a pregnancy using ART, particularly if you have an illness that has already affected the quality of your sperm. We analyze sperm prior to cryopreservation to provide insight into their viability.

Our physicians will discuss your unique situation and needs with you to determine the most appropriate path for cryopreservation and beyond.

Some individuals have ethical concerns with cryopreservation. Each person or couple must form their own opinions and make the choices best for them. We are happy to discuss any concerns with you.