Pacific Fertility Egg Bank - 3rd Anniversary!
As Pacific Fertility Egg Bank (PFEB) marked its third anniversary in August, we found much to celebrate. Our vision remains that of broadening access for patients who want to expand their families by using donor eggs. To that end, we recently celebrated our 100th embryo transfer and 45th birth, and are expectantly awaiting delivery of several more. In addition, we have also grown the number of donors available for selection as requests for frozen donor eggs increase.
Frozen vs. fresh. Published in the August 11 issue of the Journal of the American Medical Association (JAMA), the study looked at 11,000 in vitro fertilization (IVF) procedures using donor eggs in 2013data that had been collected from U.S. fertility centers by the Society for Assisted Reproductive Technology (SART). The data showed that, overall, frozen-egg cycles resulted in a live birth rate of 47 percent, while fresh-egg cycles resulted in live births 56 percent of the time.1
How much should you read into these numbers? Its worth a closer look.
Apples to oranges. Its difficult to make sweeping generalizations from overall statistics such as those provided by the JAMA report. Methodologies, course of treatment, and patient populations differ between institutions. In addition, not all clinics have the high level of technical proficiency that cryopreservation requires.
Also, the science and experience of most centers has advanced greatly since 2013. More clinics than in the past are using vitrification, an ultra-rapid freezing technique. For these reasons, it is likely that current numbers would paint a very different picture than those gleaned from the JAMA study.
For now, its most useful to look at current clinic-specific results. In fact, when the American Society of Reproductive Medicine (ASRM) removed the experimental label from vitrification in January of 2013, it cautioned that success rates may not be generalizable, and clinic-specific success rates should be used to counsel patients whenever possible.
PFC success rates. With many years of experience and a high-volume patient population, PFCs success rates are currently better than the national average. For starters, we have an 86 percent thaw rate and 85 percent fertilization rate with our frozen donor eggs. And, our pregnancy and delivery rates for our fresh and frozen cycles are virtually the same.
For fresh donor eggs, we have a 62 percent clinical pregnancy rate (an intrauterine pregnancy with a gestational sac seen on ultrasound at 79 weeks) and a 52 percent delivery rate. For frozen donor eggs, the clinical pregnancy rate is 60 percent and delivery rate is 55 percent.
When we started our egg donor program, we vitrified eggs from donors that had already completed fresh egg donation cycles. Once we started thawing these donors frozen eggs, we had a convenient point of comparison. We found that frozen eggs performed similarly to their fresh donor egg siblings. In fact, we rarely see a significant difference between how a donors eggs perform, whether fresh or frozen.
Behind our success. To what do we attribute our success? We have extensive experience with cryopreservation, and were among the first to begin using vitrification to freeze eggs. In 2006, we adopted this technique to help protect eggs, which are most susceptible to injury right after removal from the ovaries. Vitrification has become a highly reliable method for preserving these delicate eggs. The technique worked so well, we quickly began using it to cryopreserve embryos as well.
The technology has continued to evolve in the last 10 years with changes in the composition of cryoprotectants, time of exposure, and carrier devices. Today, PFCs expertise is so highly regarded that our embryologists teach vitrification courses, advancing the technology to optimize its use and improve outcomes around the world.
Kushnir VA et al. Outcomes of Fresh and Cryopreserved Oocyte Donation. JAMA. 314(6):623624.