The physicians and staff at Texas Fertility Center were so sorry to hear about the tragic recent events at University Hospitals Fertility Center in Cleveland and Pacific Fertility Center in San Francisco.
Despite the fact that all IVF laboratories have some level of systems in place to safeguard against an event just like this, a major malfunction apparently occurred that potentially affected thousands of frozen embryos and frozen eggs. These are obviously tragic events, and we want to convey our heartfelt sympathy to the patients, as well as the physicians and staff at both fertility centers.
We all understand the responsibility of safeguarding our patients’ genetic material, and an event like this is devastating to everyone involved. Although the specific events surrounding these tragedies are still unknown, there are several things that we do know. We all know that, in the forty years since the birth of the first IVF baby, physicians and IVF laboratory personnel have been devoted to developing systems that both anticipate and prevent a tragedy such as this. As a result, despite performing over 150,000 IVF cycles in over 500 IVF laboratories in the US every year, events such as these are extremely rare.
There are many reasons for this, including fact that physicians and IVF laboratory personnel from around the world work together to share best practices for laboratory safety and security. We also work closely with industry to design better storage tanks and early detection systems that can immediately alert us to any potential problem. Each of our laboratories is certified and licensed by federal and state agencies that regularly review our policies and procedures. As part of this process, IVF laboratories are subjected to regular as well as surprise inspections by CAP, CLIA, and the FDA.
Regardless, events like these understandably cause concern for our patients. For this reason, we would like to take the time to describe the specific safeguards that we have in place to prevent – as much as humanly possible – anything like this from happening at TFC.
First of all, it is important to understand how frozen embryos are stored. Rather than storing them in freezers that require electricity and are subject to a variety of potential mechanical issues, power outages, and/or unanticipated defrost cycles, frozen embryos are stored in large insulated tanks. These tanks have an outer layer of stainless steel that surrounds many layers of thick insulation. This insulation is necessary, as liquid nitrogen has a temperature of -321O Fahrenheit. At this temperature, cellular metabolism ceases, which explains why embryos, eggs and sperm can be successfully frozen for many years and can still function normally after they are thawed.
Each sperm, egg, or embryo specimen is clearly labeled and individually stored in thick walled cryo devices that are specially designed to be able to withstand these extreme temperatures. They are then placed into the bottom of each large cryotank, submerged in the liquid nitrogen. One of the major characteristics of liquid nitrogen is that if it’s temperature rises, it starts to boil – leading to evaporation of the liquid. For this reason, the temperature of each cryotank is closely monitored using state of the art temperature sensors. These sensors wirelessly transmit information to monitors located in the laboratory as well as to an alarm system.
When liquid nitrogen is stored in a cryotank, it actually exists in two forms – liquid and vapor. The liquid layer is at the bottom of the tank, while the vapor is at the top. Even at its normal temperature, liquid nitrogen slowly evaporates. Therefore, our laboratory personnel perform daily inspections to monitor the level of the actual liquid form of nitrogen. Storage tanks come in various sizes, but our large tanks typically contain around 40 inches of liquid. Therefore, every day, our personnel confirm that the liquid level is appropriate, adding additional nitrogen as necessary, to keep all specimens in the more stable liquid phase. As the temperature sensors are submerged in the liquid and not the vapor phase, the slightest change in temperature will alert our staff of any variance. The normal level of evaporation is so slow that, even if we did not add any liquid nitrogen on a regular basis, it would take several weeks for the level to fall below the level where specimens are stored. Due to the multiple layers of regular insulation and vacuum insulation, a catastrophic leak is very unlikely. Regardless, in the unlikely event of a leak, the sensors are designed to detect the slightest rise in temperature. They then send a signal to the monitors, which generate an audible alarm heard throughout the laboratory. The alarm system is also programmed to call our laboratory director immediately, as well as send text and email messages in the event of an alarm, so that he can respond and deal with any problem.
While we do store genetic material onsite for TFC patients who are currently undergoing an IUI, IVF, or FET cycle, we encourage all other patients to allow us to send their specimens to Ovation Fertility’s long-term storage site. Ovation has built a secured site specifically for long term storage, equipped with state of the art onsite and 24-hour video monitoring. The site is staffed by experienced personnel dedicated to ensuring the safety and security of your genetic material.
Again, while we are all awaiting more information from Cleveland and San Francisco, we want you to be able to rest assured that we have rigorous policies and procedures in place to guard against any such eventuality occurring here. Having said that, we can assure you that we will thoroughly review information as it is released from Cleveland and San Francisco to ensure that we can improve our procedures if necessary. We remain confident that the safeguards that exist, both at TFC and Ovation, are well designed to minimize any risk to your genetic material. We encourage you to contact us if you have any additional questions.