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IVF Embryo Culture

Learn about the importance of IVF embryo culture

The process of IVF embryo culture after egg retrieval lasts five to seven days. During this important time, our San Antonio IVF center nurtures and monitors the development of the embryos (fertilized eggs).

The process of IVF embryo culture

After the egg retrieval is completed in the morning, mature eggs are inseminated (mixed with sperm) later that afternoon. This is done either through standard insemination (we combine eggs and sperm in a dish, may the best sperm win) or ICSI (we inject the best-looking sperm into the egg). The eggs are then placed in an incubator that gives the best environment for fertilization to occur. The day of the retrieval and insemination is called Day 0.

The next morning (Day 1), the embryos are briefly removed from the incubator at our San Antonio IVF center. The embryologist determines which embryos have normal fertilization and then places the embryos back in the incubator to continue their developmental journey. You will receive a phone call from the embryologist on this day with a personal update. We repeat this on Day 3 of IVF embryo culture.

Embryos are not removed from the incubator on Day 2 or Day 4 for a few reasons. First, every time the incubator is opened, it changes the environment within the incubator (temperature, humidity, etc.). We want to minimize those changes as much as possible. Also, embryos undergo a major metabolic stress on Day 2 and Day 4. Knowing how the embryos respond to that stress and how many continue to develop gives the embryologists at our San Antonio IVF center more information about the quality of the embryos that are developing.

On Days 5 through 7, the embryologist will look at the developing embryos daily and call you with personal updates. The embryos that have the best chance of becoming a baby will become an advanced stage embryo called an expanded blastocyst. About 1/3 of embryos that are fertilized on Day 1 will reach this stage.

Expanded blastocysts are graded based on the part that will become the baby and the part that will become the placenta. Embryos that undergo IVF embryo culture at our San Antonio IVF center and have reached this very important stage are then transferred to the uterus for a fresh embryo transfer, biopsied (sampled) to determine whether the embryos are chromosomally normal (PGT-A) and then cryopreserved, or simply cryopreserved for future transfer.

We can answer all of your questions about IVF embryo culture

If you have any questions about IVF embryo culture or any other step of the IVF process, please contact us. We are here to help you on your fertility journey.