Research

What about cIVF - conventional InVitro Fertilization?

The original test tube baby was IVF - activated sperm and mature oocytes (eggs) were placed in a test tube, let fertilize for a while, then placed in an incubator and waited to see if any cells started dividing.

Although that is an over simplification, equine research scientists have been trying for many years to perfect the process of activating stallion semen, co-incubating it with mare oocytes, resulting in fertilization of the oocytes, development of an embryo and ultimately, the birth of a live foal.

Since 2024, we have performed 601 recipient mare aspirations to recover 5311 oocytes for research into the mysteries of cIVF. Due to the multiple factors involved the the process of capacitation of the sperm, coincubation of the eggs with the sperm, and culture of the fertilized eggs until they are embryos, we had a lot of failures and a few successes. In addition, we were using cooled, extended semen from other ranches usually the second day after it was collected. Also, we were trying frozen semen from many different stallions.

From that 5311 oocytes (eggs) we collected, we made 202 IVF embryos, some of which were frozen and some were transferred fresh into recipient mares.

The chart below shows our results since our most recent protocol for use with FRESH SEMEN that was extended, shipped to us and used the next day or the second day.

(*Good Eggs - on average, 60 to 65% of the aspirated eggs mature and can be used for ICSI. These eggs are evaluated when they are stripped - outer cells are removed - and the interior of the eggs become visible. Eggs that failed to mature and irregular eggs will be discarded. However, with cIVF, the outer layer of cells is not removed as they play a vital role in natural fertilization. Therefore, we do not know how many "good eggs" there are so we estimate 65% of the processed cIVF eggs are "good")

As illustrated in the above chart, we recovered 60% more embryos from aspirations

processed by cIVF than from ICSI. We published these results in the article below

presented at the 2025 International Embryo Transfer Society meeting.

Additionally, we evaluated the transfer success and early pregnancy loss rate of both fresh and frozen cIVF embryos. Pregnancies were terminated at 35 days after heartbeat was confirmed.

Number transferred Number pregnant Number lost before 35 days

Frozen - 11 8 -72% 0

Fresh - 12 9 - 75% 0

Of the 12 fresh transfers, 9 became pregnant, none were lost for 75% at 35 days. Of the 11 frozen transfers, 8 became pregnant, none were lost - for 72% at 35 days. This pregnancy rate was similar to the transfer pregnancy rate for ICSI embryo transfers, however, the pregnancy loss rates before 35 days were 17% lower than ICSI loss rates.

In conclusion, our work to date Invitro-Fertilization:

1: We produced more embryos with cIVF than ICSI

2: Pregnancy rates after transfer were similar to ICSI

3. Pregnancy loss rates were much lower than ICSI

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on our 2026 "No Risk cIVF" offer.