Differential pH in embryo culture Martha Hentemann, M.D., Karim Mousavi, Ph.D., Kjell Bertheussen, Ph.D.  Fertility and Sterility  Volume 95, Issue 4, Pages 1291-1294 (March 2011) DOI: 10.1016/j.fertnstert.2010.10.018 Copyright © 2011 American Society for Reproductive Medicine Terms and Conditions

Figure 1 Mouse embryos day 1. Phase-contrast micrographs (original magnification ×100). (A) Good-quality embryos day 1. Good two-cell embryos of strict regular morphology; blastomeres are bound tight together and with a slightly oval shape. (B) Bad-quality embryos day 1. None were accepted as good embryos. Very variable morphology: some are one cell, some fragmented, some irregular and granular two to three cell. Inset, A two cell with somewhat separated blastomeres of irregular shape. Fertility and Sterility 2011 95, 1291-1294DOI: (10.1016/j.fertnstert.2010.10.018) Copyright © 2011 American Society for Reproductive Medicine Terms and Conditions

Figure 2 Mouse embryos day 5. Phase-contrast micrographs (original magnification ×100). (A) Good-quality embryos day 5. Four large blastocysts of good morphology: three are regular hatched embryos, round or slightly oval shape, with evenly distributed cells. One is a hatching blastocyst with densely packed cells of good morphology. (B) Bad-quality embryos day 5. Phase-contrast micrograph (original magnification ×100). None were accepted as good embryos. Very variable morphology of blastocysts and cells: some embryos fragmented; some irregular or granular and showing clear signs of degeneration. Fertility and Sterility 2011 95, 1291-1294DOI: (10.1016/j.fertnstert.2010.10.018) Copyright © 2011 American Society for Reproductive Medicine Terms and Conditions

Figure 3 Three sets of embryo cultures with three pH values over the whole culture period. The media were changed on day 2. The three different colors represent three culture sets. Fertility and Sterility 2011 95, 1291-1294DOI: (10.1016/j.fertnstert.2010.10.018) Copyright © 2011 American Society for Reproductive Medicine Terms and Conditions

Figure 4 Three sets of embryo cultures; all cultures had a pH at 7.30 the first 2 days. By changing the media on day 2 the pH either was kept at 7.30 or was changed to 7.15 and 7.00. Three colors represent three culture sets. Fertility and Sterility 2011 95, 1291-1294DOI: (10.1016/j.fertnstert.2010.10.018) Copyright © 2011 American Society for Reproductive Medicine Terms and Conditions

Figure 5 Three sets of embryo cultures and three different pH values during the first 6 hours. Media were changed at 6 hours to obtain pH 7.15 in all cultures for the remaining culture period. Three colors represent three culture sets. Fertility and Sterility 2011 95, 1291-1294DOI: (10.1016/j.fertnstert.2010.10.018) Copyright © 2011 American Society for Reproductive Medicine Terms and Conditions