Evidence that obesity alters the quality of oocytes and embryos Rebecca L. Robker  Pathophysiology  Volume 15, Issue 2, Pages 115-121 (August 2008) DOI: 10.1016/j.pathophys.2008.04.004 Copyright © 2008 Elsevier Ireland Ltd Terms and Conditions

Fig. 1 Schematic of the ovary, the ovulated oocyte and resultant blastocyst stage embryo. Alterations to the ovarian environment, such as during obesity, impact oocyte developmental competence and subsequent embryo quality. In human IVF the oocyte is aspirated from preovulatory ovarian follicles and fertilized in vitro. The embryo is typically replaced into the uterus after 2 or 3 days, at the 2-cell or 8-cell stage, respectively. In our animal studies female mice ovulated and mated with males followed by removal of the fertilized oocyte from the oviduct. This zygote was cultured in vitro for 5 days to the blastocyst stage and then the embryonic cells (inner cell mass) and placental precursor cells (trophectoderm) were assessed. Pathophysiology 2008 15, 115-121DOI: (10.1016/j.pathophys.2008.04.004) Copyright © 2008 Elsevier Ireland Ltd Terms and Conditions