Every year, several Pacific Fertility Center professionals participate in ASRM’s national meeting. They evaluate the research and share their findings with PFC and Fertility Flash.

Among those attending the conference from PFC were Dr. Philip Chenette and Dr. Isabelle Ryan and Peggy Orlin, MFT. Their reviews cover the following topics: Update #1: Ovarian Stimulation Techniques, Update #2: PGD and Aneuploidy Screening Techniques, Update #3: Egg Freezing, Update #4: Acupuncture, and Update #5: Men and ART.

ASRM Update #3: Egg Freezing

Oocyte cryopreservation is the storage of the female gamete, the egg, prior to fertilization. Preservation of fertility for single women that must undergo cancer therapy or surgery, or that must delay or choose to delay childbearing, and donated oocyte banking are all applications of oocyte cryopreservation. The need for this technology is clear, but reports of success with oocyte cryopreservation have been limited.

Highly successful oocyte cryopreservation is now attainable. New studies are showing pregnancy rates with oocyte cryopreservation that are equal to traditional IVF techniques.

The key to this technology is oocyte vitrification – an ultrarapid cryopreservation technique. Researchers from Atlanta described their experience with vitrification. Out of 11 patients with transfers, nine conceived, with an implantation rate of 65%.

Pregnancies after oocyte cryopreservation have developed normally. An Italian study of 105 children born after oocyte cryopreservation showed no problems. A Chicago study of the genetics of oocytes, embryos, and children born after oocyte cryopreservation was reassuring. No increase rates of aneuploidy or malformations were reported, and normal development was found in post-natal follow-up.

These results are similar to those we have previously reported from our own research at Pacific Fertility Center (see December 2007 Fertility Flash). Oocytes are now cryopreserved with high success rates. Oocyte cryopreservation technology has matured, and we look forward to providing these techniques for our patients.

Philip Chenette, MD

In late October of this year, our first patient who underwent embryo transfer with embryos created from vitrified and warmed donor oocytes has successfully delivered. The baby was born at term and appears to be perfectly healthy.

Three other pregnancies are ongoing and are expected to deliver in 2008. We congratulate our new parents and the parents-to-be who have participated in this ground breaking program.

PFC has ended enrollment of patients into this program, but expects to continue research efforts with respect to oocyte vitrification.

While it has been possible to preserve sperm for many years (the famed Dutch microscopist Anton von Leeuwenhoek allegedly cooled and then recovered sperm using snow and ice in the 17th century), reliable methods for oocyte preservation have been elusive.

We previously discussed some of the problems with oocyte freezing (see Fertility Flash, January 2005, Volume 3, Issue 1), and now report our success in overcoming some of the obstacles.

Traditionally, preservation of sperm and embryos has been achieved with the use of a technique called slow freezing. This process incubates the sperm or embryos in low concentrations of cryoprotectants (antifreeze) to draw water out of the cells. After this incubation, they are cooled very slowly to sub zero temperatures. Typically this slow freezing technology just works for cells that exist individually (such as sperm), or together in small numbers (embryos), as the water must be extracted from every cell. Tissues, which are made up of many hundreds of thousands of cells, cannot be dehydrated successfully and therefore cannot be frozen intact. Cells in the tissue can burst when the water remaining in the cells expands as it turns to ice. For example, it is not possible to freeze a whole ovary, but some success has been achieved with ovaries that were cut into tiny pieces.

Frustrated by the lack of progress with slow freezing, scientists have more recently moved towards a technology called vitrification for oocyte preservation. Vitrification, which was described in detail in September’s Fertility Flash (Volume 5, Issue 8 ) works by using higher concentrations of cryoprotectants and much faster cooling rates. Cells are typically cooled in tiny straws (see article heading). This process allows us to achieve cooling rates of several thousand degrees per minute.

When vitrification straws and cryoprotectants were first approved by the FDA for human embryos, PFC began the process of adapting the technology to oocytes. Our embryologists attended training courses and became proficient with the technology by practicing on mouse and hamster oocytes and embryos. Even though we have been handling oocytes and embryos for many years, this technology provided many new challenges, mainly due to the tiny size of the straws and the speed at which the cells had to be cooled. Once we became proficient with the procedure, we began to freeze high quality oocytes from donors who had proven fertility. In this way, we knew that if the procedure did not work, it would be the vitrification technology and not the oocytes that were to blame. In addition, we satisfied ourselves that the technology was safe by looking at the exhaustive work by Dr. Gary Smith at the University of Michigan, which showed that vitrified/warmed oocytes were both physically and genetically normal and that the resulting pregnancies and babies were healthy.

We recruited five oocyte donors and vitrified all of their oocytes immediately after their oocyte retrieval procedures. We then offered the oocytes to individuals who were on our waiting list to accept donated embryos. Typically, these individuals were unable to get pregnant with their own oocytes or financially unable to proceed to an egg donor cycle. The availability of the vitrified oocytes was a great alternative to accepting donated embryos as it allowed couples to choose their own sperm source. Furthermore, the immediate availability of vitrified oocytes was an attractive alternative to what may be a very long wait for donated embryos.

Pacific Fertility Center had immediate success with the first recipient. We had vitrified 16 oocytes from the first donor, and for the first recipient we warmed only 7 of these. Four hours later we injected a single sperm into each of the 6 oocytes that appeared alive and healthy (1 oocyte had not come through the process successfully). The next morning, 3 of the oocytes fertilized normally. After 2 more days, we had 3 nice embryos for transfer. The positive pregnancy test 11 days later, and a singleton pregnancy confirmed by ultrasound at 7 weeks were great rewards for our efforts and thrilling news for the recipient. Our second recipient used a different donor and although her pregnancy started out well, she miscarried in the first trimester. Our disappointment over this loss was compounded when we discovered the oocytes from 2 of the donors did not survive well when warmed. In these particular donors, we recovered high numbers of oocytes (each had close to 40) and for unknown reasons their oocytes were overly sensitive to vitrification. The next three donor cycles proceeded well and resulted in pregnancies. These 3 pregnancies are all ongoing at the time of writing. We will update readers with their outcomes at a future date.

Although we were warming relatively small numbers of oocytes (typically 6 or 7), we began to have more embryos than could be safely transferred to recipients. Our first pregnancy had been achieved after transferring 3 embryos. It is more typical, however, to transfer only 1 or 2 embryos when donor oocytes are used. Even when using only 2 embryos, multiple pregnancy rates were unacceptably high. Understandably, few patients are willing to risk a decreased chance of conceiving by transferring only a single embryo. In order to avoid high multiple pregnancy rates in a typical IVF cycle, embryos are usually cultured for 5 days to determine which embryos in a cohort have the best chance of establishing a pregnancy. However, if a patient has only a few embryos, the benefits of extended culture are less, and the transfer is typically done after only 3 days growth. With our recipients of the vitrified oocytes, we began by doing 3-day transfers. Once high success rates were evident, we elected to implement day-5 transfers, in an effort to decrease high order multiples. The last 2 pregnancies both resulted from day-5 transfers of 2 embryos each, and they are both twin gestations.

In summary, we have had 7 out of 10 embryos implant after transfer (excluding the 2 failed donors with the high oocyte numbers). This implantation rate (70%) is comparable to the implantation rates that our patients have when using fresh embryos from donor oocytes.

We are moving forward cautiously with our oocyte vitrification program and hope to use the remaining oocytes soon. While these results are encouraging and have brought great joy to a small number of our patients, there are more issues to resolve before we declare complete success. The 70% success rate was obtained with the use of the highest quality oocytes from young donors who were known to be fertile and healthy. We have already seen that some oocytes are less tolerant of the procedure, as evidenced by the results from the 2 donors with high oocyte numbers. We also fully anticipate that the results for older women using their own oocytes will be worse, as they are for these same patients using a fresh IVF cycle. In fact, at this time, we do not have any idea if the oocytes from women in their 30’s will be able to tolerate vitrification.

Going forward, we will offer oocyte vitrification unconditionally to women with cancer who are likely to be left sterile by their treatment. For these women, and for others who elect to vitrify oocytes for social reasons, we will exercise great caution in our estimates of future pregnancy potential with the warmed oocytes. Until we have more data with oocytes from a variety of women, we will have no way of telling if there is any hope from anything other than donor oocytes. That data will accumulate more slowly because women who elect to preserve oocytes are not likely to be using them for some time. For now, until there is more data, we continue to believe that embryo freezing has the greatest potential for those wishing to preserve future fertility. However, for those who are single and in their late 30’s, we will be reluctant to recommend oocyte vitrification as a reliable fertility preservation method. Hopefully, they will find Mr. Right before we have objective data.

Joe Conaghan, PhD, HCLD

Question: We hope to have embryos left after transfer and need to consider storage. Can you help us understand what determines your storage fees?

Answer: Many Pacific Fertility Center patients have surplus embryos at the end of their IVF cycle. If you chose to freeze your embryos, you will need to consider how long you plan to store the embryos before being used for a frozen embryo transfer. Patients who are finished building their family, but are not interested in destroying the surplus embryos, may choose to freeze them, offer them for adoption or donate them to research. These options are included on the consent forms, which must be signed prior to transfer.

Once you choose to freeze embryos, you need to factor in the annual storage fee. Pacific Fertility Center strives for lower fees, but must be able cover the underlying costs of services. Storage fees include expenses from the following sources: storage tanks, liquid nitrogen, leased floor space, embryologists and staff hours, equipment maintenance, annual inventory, information dissemination, forms, billing, legal fees and liability.

Let’s begin with the storage tanks themselves. At PFC we have 3 state-of-the-art embryo tanks: two tanks hold a total of 1376 spaces each. Every one of these spaces can hold up to 5 straws of embryos and each straw holds 1 to 3 embryos. These two tanks are full. Recently, we purchased another, larger tank, which holds almost 1500 patient spaces. This tank is already almost half full.

Once these tanks are filled with liquid nitrogen, they are extremely heavy. Because of their weight, they cannot be clustered together in the same room, but must be strategically placed to spread out the weight over the center’s floor. In addition, they must be stored in a secure, locked location. Every time we add a tank, an appropriate new space must be located. With square footage at a premium, this is not an easy task.

Storage tanks must be monitored. Gauges and seals must be functioning and the temperature must be kept at the optimum level with the addition of liquid nitrogen. The tanks are fitted with an alarm, which sounds if there is a problem. This alarm automatically sends an alert to the embryologist on call 24 hour a day, 365 days a year.

All embryo straws are labeled and a file is maintained for every patient who has embryos in storage. This extremely important aspect of storage is taken very seriously. A thorough inventory is completed every year. This is a time-consuming process as every straw must be located and identified. Patient addresses are kept up-to-date and confirmed annually when the invoice is sent or when patients notify the center of an address change.

If patients fail to notify us of a move and/or abandon their embryos, we make every effort to locate them. When they repeatedly fail to pay their invoice, we may be forced to send their billing on to a collections agency. During this process, we continue to store their embryos. As a last resort, we will go before a judge, show proof that we are unable to contact the patient after multiple attempts over a reasonable period of time, and request permission to discard the abandoned embryos.

One of the most frequently asked questions is “When am I going to be billed?” You will be billed based on the month that your storage begins. Patients often forget they have a back-up sample of frozen sperm and are “surprised” when they receive an invoice indicating they must pay their storage fee.

PFC is always available to answer any questions you may have regarding the storing of your embryos and sperm. For disposition questions, please contact Alexis Von Austin, Tissue Bank Manager at (415) 249-3636. For questions regarding an invoice, please contact Rosemarie S. Tagle, Billing Supervisor at (415) 249-3651.

Fresh Embryo at Blastocyst Stage: The cells are elongated and pressed against one another. The inner and outer cells are clearly visible, as is the cavity.

Two Vitrified Embryos at Blastocyst Stage After Warming: Though their appearances differ, both embryos implanted and created viable pregnancies.

This embryo looks perfect, as if it was never frozen. The outer and inner cells are clearly visible, as is the cavity.

This embryo has rounded, more dissociated cells resulting from shrinkage during incubation in cryoprotectant, (as cells shrink they pull away from each other). The cavity is small, but visible.

The first human pregnancy from an embryo that had been frozen and thawed was achieved in Australia in 1984, 6 years after the birth of the first IVF baby in the UK. The method used to preserve that embryo is called “slow freezing” and it is still the preferred method for preserving embryos throughout the world today. Slow freezing is a reliable and established technique that has served the IVF community well for over 20 years. The procedure has been refined throughout those years and it works, with slight modifications, for freezing all embryo stages and for sperm. However, despite many years of trying, slow freezing has never worked very successfully with oocytes. Frustrated by years of failures, scientists turned to an alternative procedure called vitrification in their quest to preserve oocytes. This approach is relatively new, but appears as through it will be preferentially used for oocyte preservation as we go forward. Vitrification kits are just beginning to get FDA clearance following scientific trials, and embryologists are being trained in the use of the new technology.

The main concern during the freezing of any cell is the removal of water without actually killing the cell. Since water expands in volume as it freezes, ice formation inside a cell would cause the cell to rupture and die. Therefore, cell water is traditionally replaced with a cryoprotectant (antifreeze) prior to cooling of the cell. This is achieved by sequentially incubating the cell in increasing concentrations of cryoprotectant. The cryoprotectant draws water out of the cell and itself enters the cell, all by osmosis. Once most of the water has been removed, the cell is cooled at the very slow rate of -0.3° C/minute until it has been cooled to below -30° C and is therefore fully frozen. Thereafter, storage of frozen cells is in liquid nitrogen (-196° C), which is a simple and practical storage medium.

Vitrification still requires the use of cryoprotectants and the cell is also ultimately stored in liquid nitrogen, but the journey from the incubator (at 37° C) to the nitrogen (-196° C) is much faster. The word “vitrum” in Medieval Latin means “glass” and the process turns the cell contents to a glass like substance instead of ice. Since no ice forms, the risk of rupturing the cell is eliminated. For glass to form instead of ice, the rate of cooling must be thousands of degrees per minute instead of the 0.3 degrees/minute that we use in slow freezing. Therefore, the process is sometimes referred to as ultra-rapid freezing, although the word “freezing” is really inappropriate here since the cell is not really frozen (i.e. no ice is created).

One of the big stumbling blocks during oocyte freezing was the sheer size of the cell (the oocyte is the largest human cell by some margin) and therefore its high water content. Just getting the cell to survive, (an oocyte has only one cell), was a huge stumbling block. Studies where 50-60% of the oocytes survived were considered groundbreaking, and still today there are few studies that have done better. Vitrification as a technique had been largely ignored by the IVF community as it was technically more challenging and used much higher concentrations of cryoprotectants. Cryoprotectants were thought to be toxic to cells. Today we know that they are safe and effective and do not contribute to cell death. It is possible that cryoprotectants may have deleterious effects on cells if they are metabolized, but virtually all freezing protocols utilize them at room temperature or below, where cell metabolism is significantly slowed or stopped. So, with success rates using traditional slow freezing failing to improve, vitrification has been given serious consideration as an alternative. In the few years since its introduction, vitrification has shown promising and excellent results in clinical studies (see Oktay et al., Fertility and Sterility, 2006, Vol 86(1), pages 70-80 a comparative review of slow freezing and vitrification results with human oocytes).

Making the transition from slow freezing to vitrification has been a challenge for the IVF community. As already stated, it is a technically challenging procedure, and training of embryologists in the technique has been slow. With slow freezing, embryos are placed in relatively weak solutions of cryoprotectant for as long as 15 minutes at a time. Then, they are usually moved on through slightly stronger solutions before being placed in large straws or vials which are then loaded into a computer controlled freezer for the long journey to -30° C. The embryologist can spend about 30 minutes with a set of embryos from the time that they come out of the incubator until they go into the controlled rate freezer. After 2 or more hours, the embryos can be placed in liquid nitrogen and the process is complete.

During a vitrification procedure, where typically only one oocyte or embryo can be worked on at a time, the transition from incubator to nitrogen takes only a few minutes. The embryo is stepped through solutions containing high and then higher concentrations of cryoprotectants where it shrivels and swirls in the extremely viscous medium. In the final stage, which is measured in seconds, the embryo is placed in an extremely concentrated cryoprotectant solution and then quickly loaded up into a tiny straw that is barely larger than the embryo itself. The straw is then sealed at both ends and plunged immediately into liquid nitrogen. The straw is so fine that it freezes in an instant, an important part of the vitrification process. The loading of the straw occurs at room temperature (25º C in the IVF lab) and it is cooled to -196º C in one or two seconds, giving a cooling rate of 6000-13000º C/min. The faster the straw can be cooled, the more successful the procedure. Performing this final step too slowly or too quickly can be the difference between success and failure and therefore requires extensive training.

At Pacific Fertility Center, we have been working on vitrification for over 2 years. Our initial interest was in oocyte freezing, but we were also interested in extending the technique to be used with embryos, and in particular to blastocyst stage embryos where slow freezing has not always worked well. Slow freezing has served us well over the years for embryos being frozen 1, 2 or 3 days after an oocyte retrieval, but blastocysts (5 or 6 day old embryos) did less well. With an industry wide transition to blastocyst stage embryo transfers, we looked at vitrification as an alternative method of preservation for these precious embryos.

A blastocyst is an embryo that has developed to the stage where it is ready to implant in the uterus. Instead of having a small number of loosely associated cells characteristic of earlier embryonic stages, it has 2 defined cell populations and a fluid filled cavity (or cyst). The cells that surround the cavity will form the placenta, and the cells within the cavity will develop into the embryo proper, or fetus and some of the extraembryonic membranes, such as the yolk sac. It is these interior cells that cause trouble during freezing since they are on the inside and difficult to expose to cryoprotectant. Slow freezing relies on cryoprotectant traveling through the outer placental cells, then the cavity, and finally into the fetal cells while water travels in the opposite direction. Fully dehydrating these fetal cells has always been a challenge and an embryo where these cells do not survive freezing and thawing will not result in a viable pregnancy. And with slow freezing, embryos tend to collapse in on themselves during dehydration, making it difficult to assess survival after thawing.

After investing heavily in vitrification training and implementing a successful oocyte vitrification program, PFC began working on blastocyst vitrification in January of 2007. By March we had a program established and were delighted by how easily blastocysts seemed to tolerate the procedure. Often, blastocysts looked no different after vitrification when compared to how they looked before the procedure. This result was in stark contrast to slow freezing where blastocysts always look shriveled and deflated after coming out of the freezer. By July 2007, we had switched completely to vitrification and currently we are enjoying the successes that it is bringing to our patients and us.

Our vitrification team consists of 3 embryologists: Mariluz Branch, the team leader, with Erin Fischer and Liz Holmes. Because of the technical challenges involved, we have to be cautious with involving other embryologists. So one of the three team members must be on duty every day (our lab is open 7 days a week). I am grateful to this team for their flexibility in accommodating our needs. By the end of the year we expect to have 2 more embryologists on the team, and then the final 3 in 2008.

Vitrification has been an exciting and challenging technique which we have embraced and conquered in 2007. We look forward to the gradual elimination of slow freezing and the successes that vitrification will bring us in the future.

Joe Conaghan, PhD, HCLD

Tuesday February 1st was a busy day here at Pacific Fertility Center. The front office was busy with their usual patient appointments, comings and goings for consultations, ultrasound scans and blood draws. In the procedure area and the lab, we were having one of our busier days, with 7 retrievals, 5 fresh embryo transfers and 1 frozen embryo transfer scheduled. It’s rare for us to have so many procedures on a single day, but because the exact date of a patient’s retrieval is uncertain and depends on their response to stimulation drugs, we get a day like this a few times per year. Fortunately, PFC has an exceptionally large and well-equipped laboratory, so we can cope easily with variations in case load. Also, both our nursing and embryology staff schedules are flexible enough to allow us to schedule extra staff when necessary. On that Tuesday for example, we had 8 of our 9 embryologists on duty in the lab

Even though most patient appointments don’t happen before 8 AM, lab and nursing staff are here between 7 and 7:30 in the morning to open up the facility and perform the usual quality control (QC) checks before the work day can begin. In the lab, once all QC and start-up procedures have been completed and documented, we begin looking at embryos that are to be transferred that morning, thawing frozen embryos for transfer, evaluating fertilization for the previous day’s patients, retrieving eggs and processing sperm samples. The nursing staff is busy checking in patients for retrievals, doing all their pre-operation checks and setting up IV bags, and coordinating patients for embryo transfers. Mornings are definitely our busiest time; we do this every day (7 days a week) so we like to think that the work flows smoothly.

At approximately 8:30 AM, right in the middle of the action, the power to our building and to those in a 10-block radius, went out. When a power outage occurs, there’s a split second when everything goes dark, but before you can think about it, emergency power kicks in and we almost seamlessly continue working. However, as part of our procedures for disaster preparedness, we have protocols for working during a power outage, and these immediately become active. First we check our emergency power generator and then all vital equipment to make sure that everything has power and is functioning normally. In the lab, one of our 15 incubators reset itself and went into calibration mode, so we simply moved its contents to a new home. No other problems or incidents occurred that day. We completed all retrievals and transfers in the usual way and our biggest concern was simply wondering why the power had gone out.

On the nursing end, patients were escorted up and down 5 flights of stairs because the elevators shut down, but otherwise their day was uneventful.

Emergency procedures and back-up power are a vital part of our operation. Our emergency generator will run our facility for 36 hours, or longer with the addition of diesel to the tank. The generator gets a 30-minute test run and an inspection every week. It receives a full service a minimum of 4 times a year and immediately after any power outage. After this instance, a service technician checked the generator and refilled the tank.

In the event there is a power failure when no one is present, the system will automatically switch over to back-up power. The alarm system in the lab then proceeds to dial each embryologist in turn on his or her home and cell phones until the call is received and verified with a code. All vital equipment is alarmed which enables us to check the status of the equipment from a remote location. We also have auditory monitoring capability and can listen to the background noise in the lab (such as a fire alarm) at any time. If it is necessary, we are prepared to have an individual physically present in the lab within 30 minutes of getting an alarm call.

Embryos and sperm in freezers don’t actually need power at all, provided that we physically fill the cryo tanks with liquid nitrogen once or twice a week. The computers that usually monitor and automatically fill these tanks do need power of course, but they are not essential to maintain refrigeration.

On February 1st, power was restored after 90 minutes, however we never know the time or duration of a power outage. At Pacific Fertility Center, we remain well rehearsed and prepared, just in case it happens on the busiest morning of the year.

Many patients receiving medical care for infertility will use cryopreserved (frozen) sperm, oocytes and/or embryos at some time during their treatment. Here in the PFC laboratory, we routinely cryopreserve sperm and embryos. We also receive specimens from sperm banks nearly every day. All of these specimens are stored on-site in our secure tanks with continuous monitoring. All specimens are stored in liquid nitrogen at -196ºC. Movement in or out of the tanks only happens when specimens are transferred post freezing or retrieved for thawing or shipping. We store sperm and embryos for our patients for an annual fee as long as we are able to maintain yearly contact with them and the annual storage agreement is renewed.

The shipping of tissues that are frozen and stored at such a low temperature is not easily accomplished. The liquid nitrogen in which they are stored is not toxic in any way, but it is extremely dangerous and can cause serious injury and even death if not handled properly.

In attempting to transport tissues that are normally stored in liquid nitrogen, we have to use a device that will keep the tissues in their same deep frozen state. This is accomplished using a “Dewar” which resembles a large thermos. A Dewar is a vacuum insulated container, mostly filled with an absorbent lining that soaks up liquid nitrogen. The Dewar is “charged” prior to use by filling it with liquid nitrogen over successive days until it will absorb no more. Once saturated, the excess liquid is poured off and the Dewar is then ready for use. Specimens are loaded into the hollow core and they are maintained in their frozen state by the cold nitrogen vapor evaporating from the surrounding absorbent layer. The Dewar holds an appropriate temperature for as long as nitrogen remains inside. Loss of nitrogen by evaporation happens continuously. Typically a fully charged Dewar maintains temperature for between 7 and 30 days depending on its size, how often it is opened and how well it was charged before use. With any Dewar however, loss of refrigeration occurs after a certain period of time, unless more nitrogen is added. In addition, dropping the Dewar or otherwise damaging it in any way can crack the container and this will result in instant failure of the vacuum seal with subsequent loss of nitrogen and thawing of the contents.

When we receive a shipment of sperm from a bank, there is always a risk that the Dewar was damaged or that there was a shipping delay that was longer than the life of the liquid nitrogen in the tank. If the specimens have thawed, typically the sperm bank will replace them at no cost. However, their liability is limited to replacing the sperm, and if you just lost the last 3 vials of your favorite donor, you’ll have to choose a new donor.

Shipping of embryos is a much more risky proposition. Embryos can’t be replaced in the same way that a sperm sample can be replaced, if they can be replaced at all. The major shipping companies such as FEDEX, UPS and DHL will not knowingly accept embryos for transport and therefore would not have any liability for loss. At PFC we discourage shipment of embryos due to the risks involved. We will not ship embryos from our laboratory on your behalf, however you can come and collect your embryos in person and ship them yourself. We will ask you to sign papers releasing us of any liability once the embryos leave our office. We cannot accept any liability for embryos that are being shipped in from elsewhere; it is a practice that we discourage.

If you absolutely must ship embryos, we suggest that you contact a company that has the expertise and the experience to make this type of shipment as safe as possible. Locally, we recommend “Swift Stork Courier” (www.swiftstork.com) who will arrange collection and delivery of the embryos and ensure appropriate and safe handling during transport. For long distance shipments, we put patients in contact with “Kynisi Courier Systems” (email: kosta@kynisi.com), a company based in the UK that specializes in shipping embryos. If you want to send your embryos from

San Francisco to Detroit, or Dublin or Dubai, Kynisi is the only company we know that can get embryos on airplanes without being x-rayed in security. They also get advance clearance to make sure that embryos don’t get delayed in customs as they cross international borders. Kynisi can also arrange for an embryologist to travel with your embryos, and they can organize for the embryos to travel in the passenger cabin of the aircraft, as opposed to being thrown in the luggage compartment with the other cargo. This is important, as a Dewar left lying on its side will lose nitrogen more rapidly than when upright. Kynisi’s services aren’t inexpensive, but considering that the embryos are priceless, there really isn’t a good alternative.

For those patients considering moving their frozen tissues to a facility that offers long-term storage at reasonable costs, we recommend “ReproTech” (www.reprot.com) in Reno, NV. ReproTech is experienced and knowledgeable, and gives great customer service. They too can arrange safe movement of your tissue from us to them, and back again with minimal inconvenience. They often take the extra precaution with embryos by splitting them into 2 groups that are then shipped separately. ReproTech shares the PFC philosophy of thinking of embryos as irreplaceable, and they take every known precaution to ensure a safe and efficient shipment. However, despite the good work of ReproTech, Kynisis and others, I recommend that you do not ship your embryos. The risks are too great.

Joe Conaghan, PhD

The American Society for Reproductive Medicine’s (ASRM) annual meeting was held in New Orleans. It is the largest meeting for reproductive medicine specialists and scientists in the world. From our practice, Dr.s Givens, Schriock and Conaghan attended, as well as embryologists Jean Popwell, PhD and Jennifer Andres. Also, PFC nurse Allison Chamberlaine and PFC’s Marriage and Family Therapist Peggy Orlin attended. In addition, the genetics counselor with whom we work closely, Lauri Black from California Pacific Medical Center, was an attendee and active participant.

PFC’s embryologists attending ASRM’s research poster session Jean Popwell, PhD (left) and Jennifer Andres (right).

Single-Embryo Transfer: Minimizing Risks & Maximizing Outcomes
Dr. Givens attended a post-graduate course entitled “Moving Toward Single-Embryo Transfer: Minimizing Risks and Maximizing Outcomes.” This two-day course dealt with a pressing issue in assisted reproduction: the high incidence of multiple gestations. With the ever-increasing success of in vitro fertilization and the significant improvement in embryo implantation rates, the incidence of twin and higher-order pregnancies has risen dramatically in this country. Many countries now regulate the maximum number of embryos that can be transferred into the uterus at one time. The course topics included a summary of optimal medication protocols, several lectures on pre-cycle evaluation and testing and embryo transfer techniques.

Oocyte Freezing, PGS & Blastocyst Embryo Transfers
On the laboratory side, there were several talks on evaluation of eggs and embryo selection techniques, embryo freezing technology, including a debate about the usefulness of pre-implantation genetic screening (chromosome analysis of embryos) embryo selection. The combination was a fascinating mixture of new ideas, refinements in current technology, as well as a welcome opportunity to network and discuss with others the latest developments in reproductive science. Topping the list of presentations in New Orleans were those concerning the continuing refinements in oocyte freezing technologies, the more selective use of preimplantation genetic testing and the ongoing scrutiny of blastocyst stage embryo transfers.

Slow-freeze vs. Vitrification
The traditional slow-freeze technology used so successfully with embryos for many years, has essentially stalled with oocyte freezing. It appears the slow-freeze technology has finally met its successor: a process called vitrification. Slow freezing has had very limited success with oocytes due to their large size, high water content and their extreme sensitivity to cryoprotective chemicals and to changes in temperature and pH.

Vitrification, a technology that cools cells so rapidly that ice does not form, has been such a success for oocyte freezing that many labs are now abandoning slow freezing altogether. Here at PFC, we have been developing protocols for oocyte vitrification throughout 2006 and are actively working on blastocyst vitrification. It was reaffirming to see that this technology has gained wide acceptance, and is showing excellent results.

Preimplantation Genetic Screening (PGS)
While vitrification is on the rise, it was interesting to see that another technology, Preimplantation Genetic Screening (PGS), was lacking in new improvements or viable alternatives. Embryos have been screened for extra or missing chromosomes for over 15 years now, but the technology has not advanced significantly over that time. It is still possible to count only 12 chromosomes in an embryo. Although the error rate per chromosome is very low, the accumulated error rate becomes significant as we count more chromosomes. PGS was “under the microscope” in several presentations in New Orleans and it appears PFC’s limited use of genetic screening is well justified. Specifically, PGS does not improve embryo selection and pregnancy rates in younger patients. Its use is limited in older patients because there are often too few embryos available to justify testing. The patients who benefit most from PGS are the younger patients who experience recurrent miscarriages. However, unless there is evidence that previous pregnancies were genetically abnormal, PGS may provide limited benefit to this group.

Blastocyst stage embryo transfers
While younger patients (those under 35) don’t benefit from PGS, they are the patient population most likely to benefit from blastocyst transfers. Culturing embryos for 5 days to the blastocyst stage, instead of the more traditional day 3 embryo transfer, is one of the main ways in which the laboratory staff can help in selecting the “best” embryo for single embryo transfer (SET) patients. Blastocyst culture techniques are well refined now and support the commitment within the community to transfer fewer embryos at one time. Furthermore, the promise of vitrification can reassure patients that their remaining embryos can be stored indefinitely when preserved at the blastocyst stage. Several presentations showed that blastocysts which were vitrified early, before their cavity (or cyst) had expanded too much, benefited most from the technology. In more advanced blastocysts, artificial reduction of the cavity gave superior results. It may not be long before vitrification is the procedure of choice for preserving all blastocysts.

2006 ASRM guidelines for numbers of embryos to transfer
The new 2006 ASRM guidelines for numbers of embryos to transfer were presented. See Tables 1 and 2 below.

The topic of whether or not federal or state legislation should regulate the maximum number of embryos to transfer was also discussed. Many people in the general public support such legislation but those of us in the field (and most patients) are opposed to the government regulating medical practice and arbitrarily setting limits on embryo transfer. In order to forestall such legislation, it is obvious that we must decrease the number of twin gestations (the number of triplet and higher-order gestations has already dramatically decreased in the last 5-7 years). At Pacific Fertility Center we have instituted a new emphasis on single embryo transfers and expect to significantly reduce the risk of multiples and achieve our goal of “optimal” pregnancy outcomes. (See From Us to You in this issue for a discussion of our 2006 statistics and please see Conception Health in this issue for a discussion of why it is important to try to achieve single baby conceptions.

– Carolyn Givens, MD and Joe Conaghan, PhD

ICSI Overview: Intracytoplasmic sperm injection (ICSI) is a technique used in the IVF laboratory to inject individual sperm into eggs. The procedure was developed in Belgium in the early 1990′s (Palermo et al., 1992) and it revolutionized the treatment of male factor infertility. Prior to ICSI, men with moderate and severe fertility issues had little or no chance of having their own genetic children. ICSI has so revolutionized the treatment of infertility that it is used in the majority (55.6%) of assisted reproductive technology cycles in the United States (CDC National Summary and Fertility Clinic Reports, 2003).

When IVF is performed without ICSI, it is common to incubate individual oocytes in a petri dish with about 100,000 sperm. Usually these sperm have been obtained by processing the semen in such a way as to be able to isolate sperm that look normal and swim energetically. Only the best 10% of the sperm in a normal semen sample are used, and in the petri dish, these compete for the honor of fertilizing the oocyte.

When ICSI is employed, individual sperm are isolated and forcibly injected into the oocyte by an embryologist. The oocytes have to be incubated in the enzyme hyaluronidase to remove the cumulus cells that surround them (naturally, these cells would be dislodged by the many sperm that try to penetrate the oocyte). Prior to injection, the sperm may be processed (as above) but often there are so few sperm available that processing is minimal. Once selected, the sperm is immobilized by breaking its tail. This is accomplished by dragging the injection needle across the tail until a visible kink or break can be seen. The immobilized sperm is then aspirated into the needle, which is pushed through the shell surrounding the oocyte and then through the cell membrane. The elasticity of the oocyte membrane is such that the embryologist must be rough with it to get through. Piercing the membrane is usually achieved either by poking it several times or by aspirating the membrane into the needle until it breaks. Once the membrane breaks, the sperm can be dropped inside the oocyte.

Technically, ICSI is one of the most difficult procedures to perform in the IVF laboratory and it requires a talented embryologist to do it well. As well as being responsible for choosing “the sperm”, the embryologist must work quickly and be firm enough to break the sperm tail and oocyte membrane while not being so aggressive as to kill the oocyte. ICSI has been so successful as a technique that it is now widely used in cases where there is no male factor infertility. In fact, of all the ICSI cases performed nationally in 2003, only 53% had a male issue (CDC, 2003). While ICSI is absolutely indicated for low sperm counts, decreased sperm motility, abnormal sperm morphology (size and shape) and surgically retrieved sperm, its use has expanded to include cases with anti-sperm antibodies, previous low fertilization with IVF, low oocyte numbers, frozen-thawed sperm and ejaculatory dysfunction such as retrograde ejaculation. In addition, ICSI is being widely used for patients having preimplantation genetic testing because it avoids DNA contamination during embryo biopsy by the many sperm that are usually attached to the shell of the embryo.

ICSI Risks: In assessing the risks of ICSI, we must first look at the procedure itself. In piercing the cell membrane, our greatest concern is in avoiding the area within the oocyte where the DNA is located. This is done by orientating the oocyte such that the polar body (a small packet of discarded DNA) is placed at the 12 or 6 o’clock position and the needle inserted at 3 o’clock. The polar body is the most practical indicator of where the oocyte DNA is located since it is created by the division of the oocyte’s total DNA just prior to ovulation. However, the DNA may not always be in the assumed place so a theoretical risk of damage exists, and chromosome breakage has been observed as being higher in ICSI-derived embryos when compared to conventional IVF embryos (Bergere et al., 1995; Edirisinghe et al., 1997).

In addition to DNA disruption or damage, the physical and biochemical disturbance that occurs could be significant. The injection procedure could introduce foreign material into the oocyte such as culture medium, seminal fluid with or without bacteria (Michelmann et al., 1998), viruses (Brossfield et al., 1999), or in theory, even prions (Lacey & Dealler, 1994) or foreign DNA.

Following the ICSI procedure, the fertilization process is known to be different than with conventional IVF with atypical decondensation of the sperm head resulting in delayed replication of the male genome. This is thought to result from the injection of the intact sperm into the oocyte since such sperm retain their acromosomal cap and perinuclear theca, both of which are normally lost as the sperm penetrates the shell of the oocyte. There is marginal evidence that the sperm sex chromosome is preferentially located in the anterior head and therefore might be impacted by the delayed decondensation caused by retention of the cap (Luetjens et al., 1999).

Currently there is no evidence that the miscarriage rate is different between ICSI and IVF pregnancies, and the incidence of prematurity and low birth weight babies (7.6% and 10.3% respectively for ICSI) is similar to that for IVF in large studies (Wisanto et al., 1995; Aytoz et al., 1998), but slightly higher than rates found in natural pregnancies. These outcomes have been confirmed in a large US-based study (Schieve et al., 2002) showing overall lower birth weight and higher perinatal mortality in children conceived with the help of reproductive technologies, but no significant differences between ICSI and IVF.

In the mid 1990′s ICSI had become a routine procedure in the world of assisted reproductive technology (ART) and was being widely used. However, reports surfaced indicating that the resulting children had a high incidence of chromosomal abnormalities (In ‘t Veld, 1995; Van Opstal et al., 1997). The immediate response from the ART community was a flurry of scientific papers refuting the findings, but ultimately the conclusions of the studies were confirmed by large scale, prospective systematic follow up studies on the ICSI children. Instrumental in these studies was the Brussels University where ICSI was invented. Thorough pre- and postnatal testing showed an abnormal karyotype in 2.6% of the ICSI pregnancies (Bonduelle et al., 1999) and in a subsequent study, 3% showed a chromosomal abnormality (Bonduelle et al., 2002). Novel chromosome abnormalities increased threefold (1.6% in ICSI vs. 0.5% in the general population) and these were mostly comprised of sex chromosome aneuploidies with a smaller number of autosomal structural anomalies. Inherited chromosomal abnormalities increased fourfold in ICSI pregnancies (1.4% compared to 0.3% in the general population) and this was related to the higher rate of existing chromosome abnormalities seen in the parents (mainly the fathers). It is important to point out that the incidence of these sex chromosome aneuploidies and structural abnormalities is inversely related to the number of sperm in the ejaculate and is therefore higher in ICSI fathers (4.8% vs. 0.5% in the general population), and interestingly also higher in ICSI mothers (1.5%: Van Assche et al., 1996). The structural chromosome abnormalities include deletions of sections of the Y chromosome in some men with low sperm counts which will be passed directly to sons created by ICSI.

We are fortunate that the children of ICSI are being widely followed and many solid studies have appeared and continue to appear on the incidence of congenital abnormalities (these are problems that cause impaired function and require medical or surgical intervention). The most common abnormality appears to be hypospadias (a urological condition where the urethra opens under the penis instead of at the tip, and which is correctable with minor surgery) which is increased in ICSI births (Wennerholm et al., 2000). However, when evaluating these cases, the increased risk for congenital abnormalities is often reduced or eliminated when confounding factors (maternal age, infertility, multiple pregnancy, familial and pregnancy history) are factored in (Ericson & Kallen, 2001). Nonetheless, it does appear as though ICSI and IVF children do have an increased odds ration (2.77 and 1.8 respectively) for malformations that need medical or surgical intervention in early life when compared to naturally conceived children (Bonduelle et al., 2005).

Concerns have also arisen about developmental delays in ICSI children as a result of a single paper (Bowen et al., 1998) that had them scoring lower on the Bayley Scales of Infant Development at 1 year of age when compared to IVF and naturally conceived infants. However, a good number of solid papers have since been published indicating that this finding is not holding up and that ICSI children are performing normally in psychological testing as well as in their cognitive and verbal skills using the Bayley and other scales of intelligence (Bonduelle et al., 1998; 2003 Ponjaert-Kristoffersen et al., 2004; 2005).

Finally, it is worth asking if gene expression is normal for ICSI children and are problems likely to arise as the children get older? In looking at gene defects, there is emerging evidence that ART children might be at a higher overall risk for genomic imprinting errors when compared to naturally conceived children. Genomic imprinting is a process that silences one gene from a parent, specifically so that the gene inherited from the other parent can do the work. The classic example is placental growth, which is controlled largely by paternal genes. Maternal genes for placental growth are deliberately inactivated since it is considered a conflict of interest for Mom’s genes to be involved in the regulation of how much of her resources the fetus gets. Problems arise when an imprinted gene is defective, because the perfectly good copy of the gene from the other parent has been switched off and therefore cannot work. Diseases such as Beckwith-Wiedmann and Angleman’s syndromes result from not having a functioning copy of a gene and preliminary evidence suggests that these might be more prevalent in IVF children (Gosden et al., 2003). Abnormal spermatogenesis is associated with an increase in defective genomic imprinting (Marques et al., 2003), but it is probably too early to tell if imprinting errors will occur more frequently in ICSI children. Angleman’s syndrome for example occurs at most at a rate of 1/200,000 IVF births, so the impact of ICSI will be difficult to measure. Similarly, retinoblastoma (a type of cancer of the eye that is caused by a genetic defect similar to what causes imprinted diseases) has been reported as slightly higher in IVF children (Moll et al., 2003) but further studies will be required to substantiate this observation and to ascertain the specific risk of ICSI.

ICSI is an aggressively invasive procedure that deposits a single sperm, usually from an infertile father, into the oocyte of a woman who has undergone fertility treatments. The specific risk of ICSI in offspring is an increased incidence of chromosomal abnormalities which may be caused by the procedure or by the parents, or both. ICSI is a routine and overly used procedure and patients should be educated as to the risks. Of the studies cited here, none of the children examined were older than 5 years. The long term hazards of the procedure, if any, remain to be determined. See below for the complete bibliography.

– Joe Conaghan, PhD

Bibliography:

Aytoz A, Camus M, Tournaye H, Bonduelle M, Van Steirteghem A, Devroey P. Outcome of pregnancies after intracytoplasmic sperm injection and the effect of sperm origin and quality on this outcome. Fertil Steril. 1998 Sep;70(3):500-5.

Bergere M, Selva J, Volante M, Dumont M, Hazout A, Olivennes F, Frydman R. Cytogenetic analysis of uncleaved oocytes after intracytoplasmic sperm injection. J Assist Reprod Genet. 1995 May;12(5):322-5.

Bonduelle M, Wilikens A, Buysse A, Van Assche E, Wisanto A, Devroey P, Van Steirteghem AC, Liebaers I. Prospective follow-up study of 877 children born after intracytoplasmic sperm injection (ICSI), with ejaculated epididymal and testicular spermatozoa and after replacement of cryopreserved embryos obtained after ICSI. Hum Reprod. 1996 Dec;11 Suppl 4:131-55.

Bonduelle M, Aytoz A, Van Assche E, Devroey P, Liebaers I, Van Steirteghem A. Incidence of chromosomal aberrations in children born after assisted reproduction through intracytoplasmic sperm injection. Hum Reprod. 1998 Apr;13(4):781-2.

Bonduelle M, Camus M, De Vos A, Staessen C, Tournaye H, Van Assche E, Verheyen G, Devroey P, Liebaers I, Van Steirteghem A. Seven years of intracytoplasmic sperm injection and follow-up of 1987 subsequent children. Hum Reprod. 1999 Sep;14 Suppl 1:243-64.

Bonduelle M, Van Assche E, Joris H, Keymolen K, Devroey P, Van Steirteghem A, Liebaers I. Prenatal testing in ICSI pregnancies: incidence of chromosomal anomalies in 1586 karyotypes and relation to sperm parameters. Hum Reprod. 2002 Oct;17(10):2600-14.

Bonduelle M, Ponjaert I, Steirteghem AV, Derde MP, Devroey P, Liebaers I. Developmental outcome at 2 years of age for children born after ICSI compared with children born after IVF. Hum Reprod. 2003 Feb;18(2):342-50.

Bonduelle M, Wennerholm UB, Loft A, Tarlatzis BC, Peters C, Henriet S, Mau C, Victorin-Cederquist A, Van Steirteghem A, Balaska A, Emberson JR, Sutcliffe AG. A multi-centre cohort study of the physical health of 5-year-old children conceived after intracytoplasmic sperm injection, in vitro fertilization and natural conception. Hum Reprod. 2005 Feb;20(2):413-9.

Bowen JR, Gibson FL, Leslie GI, Saunders DM. Medical and developmental outcome at 1 year for children conceived by intracytoplasmic sperm injection. Lancet. 1998 May 23;351(9115):1529-34.

Brossfield JE, Chan PJ, Patton WC, King A. Tenacity of exogenous human papillomavirus DNA in sperm washing. J Assist Reprod Genet. 1999 Jul;16(6):325-8.

Centers for disease control and prevention. Assisted reproductive technology success rates. National summary and fertility clinic reports 2003 2005 Dec; United States Department of Health and Human Services.

Edirisinghe WR, Murch A, Junk S, Yovich JL. Cytogenetic abnormalities of unfertilized oocytes generated from in-vitro fertilization and intracytoplasmic sperm injection: a double-blind study. Hum Reprod. 1997 Dec;12(12):2784-91.

Ericson A, Kallen B. Congenital malformations in infants born after IVF: a population-based study. Hum Reprod. 2001 Mar;16(3):504-9.

Gosden R, Trasler J, Lucifero D, Faddy M. Rare congenital disorders, imprinted genes, and assisted reproductive technology. Lancet. 2003 Jun 7;361(9373):1975-7.

In’t Veld P, Brandenburg H, Verhoeff A, Dhont M, Los F. Sex chromosomal abnormalities and intracytoplasmic sperm injection. Lancet. 1995 Sep 16;346(8977):773.

Lacey RW, Dealler SF. Vertical transfer of prion disease. Hum Reprod. 1994 Oct;9(10):1792-6.

Luetjens CM, Payne C, Schatten G. Non-random chromosome positioning in human sperm and sex chromosome anomalies following intracytoplasmic sperm injection. Lancet. 1999 Apr 10;353(9160):1240.

Marques CJ, Carvalho F, Sousa M, Barros A. Genomic imprinting in disruptive spermatogenesis. Lancet. 2004 May 22;363(9422):1700-2.

Michelmann HW. Influence of bacteria and leukocytes on the outcome of in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Andrologia. 1998;30 Suppl 1:99-101.

Moll AC, Imhof SM, Cruysberg JR, Schouten-van Meeteren AY, Boers M, van Leeuwen FE. Incidence of retinoblastoma in children born after in-vitro fertilization. Lancet. 2003 Jan 25;361(9354):309-10.

Palermo G, Joris H, Devroey P, Van Steirteghem AC. Pregnancies after intracytoplasmic injection of single spermatozoon into an oocyte. Lancet. 1992 Jul 4;340(8810):17-8.

Ponjaert-Kristoffersen I, Tjus T, Nekkebroeck J, Squires J, Verte D, Heimann M, Bonduelle M, Palermo G, Wennerholm UB. Collaborative study of Brussels, Goteborg and New York. Psychological follow-up study of 5-year-old ICSI children. Hum Reprod. 2004 Dec;19(12):2791-7.

Ponjaert-Kristoffersen I, Bonduelle M, Barnes J, Nekkebroeck J, Loft A, Wennerholm UB, Tarlatzis BC, Peters C, Hagberg BS, Berner A, Sutcliffe AG. International collaborative study of intracytoplasmic sperm injection-conceived, in vitro fertilization-conceived, and naturally conceived 5-year-old child outcomes: cognitive and motor assessments. Pediatrics. 2005 Mar;115(3): 283-9.

Schieve LA, Meikle SF, Ferre C, Peterson HB, Jeng G, Wilcox LS. Low and very low birth weight in infants conceived with use of assisted reproductive technology. N Engl J Med. 2002 Mar 7;346(10):731-7.

Van Assche E, Bonduelle M, Tournaye H, Joris H, Verheyen G, Devroey P, Van Steirteghem A, Liebaers I. Cytogenetics of infertile men. Hum Reprod. 1996 Dec;11 Suppl 4:1-24.

Van Opstal D, Los FJ, Ramlakhan S, Van Hemel JO, Van Den Ouweland AM, Brandenburg H, Pieters MH, Verhoeff A, Vermeer MC, Dhont M, In’t Veld PA. Determination of the parent of origin in nine cases of prenatally detected chromosome aberrations found after intracytoplasmic sperm injection. Hum Reprod. 1997 Apr;12(4):682-6.

Wennerholm UB, Bergh C, Hamberger L, Westlander G, Wikland M, Wood M. Obstetric outcome of pregnancies following ICSI, classified according to sperm origin and quality. Hum Reprod. 2000 May;15(5):1189-94.

Wisanto A, Magnus M, Bonduelle M, Liu J, Camus M, Tournaye H, Liebaers I, Van Steirteghem AC, Devroey P. Obstetric outcome of 424 pregnancies after intracytoplasmic sperm injection. Hum Reprod. 1995 Oct;10(10):2713-8.