|
|
|||||
|
|
7. Factors in the Labto "Why does IVF fail?" main page a. Air QualityThe quality of the air in the IVF laboratory is crucial to the success of a program. Our current lab exceeds and addresses all of the factors I will discuss below. Our new lab, to be opened in Fall, 2008, began with a clear slate and the office was designed around the requirements of the IVF lab. Years ago, labs were literally placed in storage rooms of hospitals or in unused operating rooms. We have come a long way in our understanding of the effects of the air quality on IVF embryo development. The air can contain microorganisms like bacteria, fungi, or viruses. Chemical which are toxic to embryos, call volatile organic compounds (VOCs), may come from paints, adhesives used to put carpet down, or even perfume! The design of the Heating, Ventilating, and Air Conditioning (HVAC) unit involves special consideration and design. The system must be able to exchange the air in the room about 20 times per hour. Additionally, the duct work must have charcoal filters to remove VOCs and high-efficiency particulate air filters (HEPA) to remove particulate matter (i.e. bacteria, fungi). Thus, a powerful unit is needed to provide the pressure. Our system has additional fans built into the ductwork to balance the room pressures and provide extra pressure. The pressure in the rooms must be highest in the embryology lab and lower in the rooms as they go toward the outside corridor. This sets up a gradient that keeps germs and chemicals out. In general, the pressure should be 0.1 to 0.2 inches of water. Our system is capable of producing far more than that. The paint used in the lab should be low VOC water based paint or epoxy based. The floor should be a single sheet of vinyl rater than times where germs may hide in creases. The ceiling must be completely solid or have gasketed tiles. No air should go in either direction from above. Additionally, when construction is going on near the IVF lab, the team needs to be aware to schedule cases appropriately. It is attention to detail that make an IVF lab good. It reflects on the professionals that work there. Many programs report improved pregnancy rates when this issues are fully addressed. b. TemperatureIt should come as no surprise the temperature is important to IVF outcome. The pre-embryo exists only in the fallopian tube at 37 C in the body. Studies have shown that decreasing the temperature only 5 C will disrupt the spindle apparatus that helps the chromosomes separate. That is why the retrieval room is warm when we collect the oocytes and why the oocytes are collected into special warmed tubes prior to evaluation. The same is true for the transfer of the embryos. We do a trail transfer to be sure that the uterus is perfectly lined up and sometimes use a stylette with the outer sheath left in the cervix to be assured that the embryos will spend the minimal amount of time outside the incubator before placement in the uterus. The transfer rooms is warm as well. When done in operating rooms which are very cold, we always recommend raising the ambient temperature for the transfer. Again, it is attention to details that makes a program successful. b. LightUltraviolet light (i.e. UV, 400 nm wavelength) may be damaging to
cells. The visible light wavelength spectrum is from 400 nm to 700 nm,
thus there are concerns that light in the ART must be controlled. UV light
may be a potential stressor for the embryo and is definitely unnatural.
Filters are used in the microscopes and rheostats are used to control the
amount of light in the room when the embryos are out of the incubators.
Our goal is to make decrease all stress on the embryo and improve outcome. |
||||
|
|
|||||
