Figure 1. Embryos with more severe changes in gene expression after in vitro manipulation will manifest abnormal glucose tolerance as adults.

Different culture media and oxygen tensions in combination have distinct effects on blastocyst gene expression and adult glucose tolerance. The number indicates statistically different gene expression compared to blastocysts conceived naturally and flushed from the uterus (control). In general, suboptimal conditions such as Whitten's medium (WM) or higher oxygen concentration (20% O_x) will more severely affect embryo transcription and result in worse offspring glucose phenotypes (red panel). Conversely, optimized conditions such as K simplex optimized medium (KAA) and physiologic oxygen concentration (5% O₂) have a lesser impact on blastocyst transcription with normal offspring glucose tolerance (green panel). IVF, in vitro fertilization.