title: Combined effects of individual culture and atmospheric oxygen on preimplantation mouse embryos in vitro.
abstract: Embryos are routinely cultured individually, although this can reduce blastocyst development. Culture in atmospheric (20%) oxygen is also common, despite multiple detrimental effects on embryos. Although frequently occurring together, the consequences of this combination are unknown. Mouse embryos were cultured individually or grouped, under physiological (5%) or atmospheric (20%) oxygen. Embryos were assessed by time-lapse and blastocyst cell allocation. Compared with the control group (5% oxygen group culture), 5-cell cleavage (t5) was delayed in 5% oxygen individual culture and 20% oxygen group culture (59.91 ± 0.23, 60.70 ± 0.29, 63.06 ± 0.32 h post-HCG respectively, P < 0.05). Embryos in 20% oxygen individual culture were delayed earlier (3-cell cleavage), and at t5 cleaved later than embryos in other treatments (66.01 ± 0.40 h, P < 0.001), this delay persisting to blastocyst hatching. Compared with controls, hatching rate and cells per blastocyst were reduced in 5% oxygen single culture and 20% oxygen group culture (134.1 ± 3.4, 104.5 ± 3.2, 73.4 ± 2.2 cells, P < 0.001), and were further reduced in 20% oxygen individual culture (57.0 ± 2.8 cells, P < 0.001), as was percentage inner cell mass. These data indicate combining individual culture and 20% oxygen is detrimental to embryo development.
authors: School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia. Electronic address: kelleyr@student.unimelb.edu.au.
authors: Rebecca L
authors: RL
authors: Kelley
authors: School of BioSciences, The University of Melbourne, Parkville, Victoria 3010, Australia. Electronic address: david.gardner@unimelb.edu.au.
authors: David K
authors: DK
authors: Gardner
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000737:chemistry / Q000166:cytology / Q000502:physiology*; D060833:Cellular Microenvironment; D002970:Cleavage Stage, Ovum / Q000166:cytology / Q000502:physiology; D046149:Embryo Culture Techniques; D047108:Embryonic Development; D051379:Mice; D008810:Mice, Inbred C57BL; D010100:Oxygen / Q000737:chemistry; D059008:Time-Lapse Imaging
chemical_list: D010100:Oxygen
keywords: IVF; group culture; oxidative stress; paracrine factors; single culture; time-lapse