CO2 and Low-O2 Incubators

  • Marius MeintjesEmail author


Embryo incubators can be considered the heart of any in vitro fertilization (IVF) laboratory. Understanding the strengths and weaknesses of our incubators is invaluable and essential to optimize clinical IVF outcomes. Based on the evidence, we should culture in a reduced-O2 environment if possible and, therefore, give preference to incubators that have the ability to provide a reduced-O2 environment. Second- and third-generation top-load mini-incubators are becoming a significant alternative to conventional incubators, mainly due to the considerably smaller footprint, lower cost of operation, and superior temperature and gas-phase recovery times. However, we should be aware of the unique safety and quality control challenges posed by top-load incubators. When using conventional incubators, those equipped with infrared CO2 sensors are superior. When having to use incubators with thermoconductivity CO2 sensors, humidity control is essential and clinical outcomes can be improved by limiting the number of patients per incubator and the number of incubator door openings. The quality of incubator supply gases should be considered as important as the general laboratory air quality and filtered similarly for particles and gaseous contaminants. Compressed N2 as a source to lower O2 concentration in the incubator should be avoided. Small direct-heat air-jacketed incubators are preferred over large water-jacketed incubators. Critical incubator performance parameters should be monitored daily with independent measuring devices. There should be no less than two incubators in any facility, regardless of type of incubator or the patient volume. Incubators must be connected to a 24-h alarm and notification system, monitoring all critical incubator parameters. Knowing that more than one sound approach to IVF can yield excellent results, the goal is not to recommend specific products or solutions but rather to suggest principles and general guidelines useful to everyday decision-making.


CO2 O2 Reduced oxygen Incubator In vitro fertilization Embryo Blastocyst Human Quality control 


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Frisco Institute for Reproductive MedicineFriscoUSA

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