In Vitro Fertilization (IVF): Traditional IVF
Nitrogen and Embryo Quality
In 2008 Carolina Conceptions elected to use only a three gas system to incubate our embryos. This was in contrast to the standard two gas system used in most IVF labs that exposes embryos to 19% oxygen, as compared to our current incubator environment of 5% oxygen. This lower oxygen concentration is thought to more adequately represent the environment of the woman’s fallopian tubes and uterus and increase her chances of conception. In an article published in June 2009, Fertility and Sterility, 600 women were randomized to blastocyst culture in standard atmospheric conditions versus low oxygen, high nitrogen concentrations as are used in our lab. As was our impression the embryos exposed to lower oxygen tension did better, in most cases significantly better. There was a greater chance that day 3 embryos would become blastocysts or day 5 embryos, there would be a greater number of embryos to freeze, and the relative birth rate was increased by 10% in those women whose embryos were cultured in the way Carolina Conceptions embryos are cultured. (Walderstrom U, et al. Low oxygen compared with high oxygen atmosphere in blastocyst culture, a prospective randomized study. Fertility and Sterility. June 2009
Filters, High Pressure, Humidity and Embryo Quality
We also updated and modified our original roof filter system in 2008 to improve on the exclusion of deleterious agents that may affect embryo development. At this time the original high pressure system was maintained that blows microscopic contaminants out of the lab, retrieval and transfer rooms into other parts of the clinic. The carbon filter that collects hydrocarbons was thickened and is analyzed by an outside consultant semiannually to determine when it should be replaced. Several other prefilters were added, and the HEPA filters in the lab ceiling were maintained at their current status. The air is appropriately humidified so the embryos are in their optimal environment. Hence when you come to the retrieval or transfer rooms, which are an extension of the lab , the difference in air flow, humidity and temperature is readily appreciated.