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What is Embryo Freezing?

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Embryo freezing (embryo cryopreservation) is the process to preserve an egg that has been fertilized with a sperm to achieve the goal of later pregnancy.

It typically occurs 2-5 days following sperm fertilization of your egg that was collected during the IVF cycle. This results in an embryo (fertilized egg). Embryos may be stored and preserved for later use.

Often this may be a part of the in vitro fertilization process. In this procedure, your reproductive endocrinologist will collect your eggs following medication stimulation of your ovaries. If available and viable, multiple eggs and partner or donor sperm will be placed in a special solution in an IVF laboratory dish. After the eggs and sperm cells unite they form embryos.

Your doctor will select one embryo to perform the embryo transfer, a procedure that places the embryo in your uterus with the goal of uterine wall attachment. After successful attachment, your baby begins to grow and thrive.

Because you may have multiple healthy embryos that were not implanted, you can consider freezing them for later use.

Why Choose Embryo Freezing?

Freezing embryos has benefits over egg freezing (oocyte cryopreservation). Couples or individuals typically have higher pregnancy rates if they freeze fertilized eggs (embryos) versus unfertilized eggs. It is normally used to improve chances of pregnancy in an In Vitro Fertilization (IVF) cycle.

Freezing at various stages of growth of the embryo may be used depending on your diagnosis. Recent studies have shown that allowing the embryo to develop to a later stage (blastocyte) may improve the chance of pregnancy, although typically fewer will remain viable.

You may choose embryo freezing for short-term storage or embryo banking, which is a longer storage process.

Short-term storage goals

  • You are experiencing high hormone levels of estradiol or progesterone
  • Time to improve uterine wall conditions more favorable for pregnancy
  • Need for Preimplantation Genetic Testing (PGT) prior to uterine embryo implantation

Longer-term embryo banking goals

  • Your goal is preservation of fertility prior to cancer treatments or other circumstances that could inhibit pregnancy
  • So you and your partner will not have to complete IVF another time
  • If you already produced a baby but want to preserve an embryo for later use
  • You are considering saving embryos for donation or a specific individual
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Frozen Embryo Transfer Timeline

Once you are ready to become pregnant, you Inovi team will work with you to prepare your body for embryo transfer. You will be prescribed medication to help your uterus accept the embryo. These may include estrogen and progesterone combined with other injectable medications. This process takes approximately 2-3 weeks.

During this period, you doctor will monitor your progress through the use of ultrasound and hormone testing. Once your uterine lining is ready, the process can begin.

Now it is time for your frozen (cryopreserved) embryos from a previous In Vitro Fertilization (IVF) Cycle to be thawed and transferred to your uterus.

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