Concerns about the paper "A descriptive study of culture media in Brazilian assisted reproduction clinics"

Dear Editor, With great interest we read the article in the recent issue of JBRA by Bartmann et al. (2016) on the use of culture media by IVF clinics in Brazil. Besides the information on current media usage by IVF laboratories, Bartmann et al. (2016) also list the components from the media currently in use. In the media profiles section, the authors provide information about the components in the different media used in IVF laboratories in Brazil. It appears to us that this section has limited information, justifying a rectification to avoid confusion for the readers. There is a lot of information and discussions available on the development of modern culture media and its components. Specifically for the G-series media, the full composition of an earlier version of the media has been published (Lane et al., 2003). More recently, Morbeck et al. (2014a) published an analysis on the composition of commercial culture media, including various of the media discussed in the paper by Bartmann et al. (2016). Additionally, specifically for Vitrolife media, the medium components used are available for customers on the lot-specific certificate of analysis included in every media shipment. In general, the authors state that information is missing for certain products or is unclear about the presence of components and cannot, therefore, be listed. It is unknown to us if the authors contacted medium producers to obtain more detailed information. Considering the availability of all this information, we were very surprised about the missing information on Vitrolife and other manufacturters' culture media composition. For relevant papers such as the study by Bartmann et al. (2016) Vitrolife is willing to provide useful information. Culture medium is a crucial item in an IVF treatment. We feel that it is important to provide correct information and hereby would like to add important information not provided by Bartmann et al. (2016). The authors state: " only 3 media have dipeptides in their composition … ". Vitrolife introduced a more stable form of glutamine in culture media very early on (Lane et al. 2003). Since then, the use of a more stable form of glutamine has gradually been introduced by most medium manufacturers. It has been shown in a number of studies that ammonium can affect embryo development; and very recently it was shown that, compared to a more stable dipeptide, the presence of glutamine results in very high ammonium levels during incubation …