Dry vs. Humidity Incubators: What’s the Difference?

Incubators are some of the most indispensable devices within an In Vitro Fertilization (IVF) laboratory. Through the years, these incubators have undergone various changes and advances in their physical form and design, to their features. From the conventional CO₂ incubators to the bench-top models to incubators using time-lapse system, this technological wonder has come a long way.

Bench-top incubators are some of the most notable and frequently used in the IVF lab. They are able to offer customized culture chambers and cutting-edge technology with the aim of improving environmental stability for developing embryos. Such incubators come in dry or humidified models. Basically, the dry and humidity incubators have the same features except for the fact that a humidity incubator has built-in humidity sensor for more accurate and continuous reading of humidity source. Noteworthy to mention is the point that incubators initially made use of thermal conductivity CO₂ sensors wherein moisture was a vital component to the impeccable performance of such sensor. Eventually, infrared CO₂-regulating sensors have replaced such conductivity approach, bringing about development of moisture-free incubators.

Concerns in the IVF clinic such as smaller workspace paved way for the development of scaled-down version of some of these IVF devices. Incubators with smaller footprint have become an essential consideration in the choice of such device. Such “mini versions” are similar to their original counterpart, only that their physical structure has been reduced for them to be conveniently accommodated within a lab that has limited space.

Common questions about the use of “mini dry and humidity incubators”:

Question: What is/ are the difference/s between mini dry incubator and the regular ones?

Answer: The mini dry incubator is just a scaled-down version of a regular one. It means that it has a smaller footprint; hence, it could fit in IVF laboratories with minimized spaces. Take the case of an Esco Medical MIRI ®incubator and its Mini MIRI® Dry and Humidity incubators. A regular MIRI® incubator has 6 fully independent culture heat chambers (each with its own heated bottom, heated lid and a heating optimization plate), while the mini one has only 2.

Another difference is noted on the N₂ gas consumption wherein the Mini MIRI® Dry makes use of <8L/h N₂ gas while the humidity model utilizes approximately <12L/h. Other than these variances, the key features like the speed of recovering temperature and gas parameters after opening a chamber, to the built-in gas mixer and the high-performance CO₂ and O₂ sensors, are generally the same.

Question: What is/ are the advantage/s of a compact designed MIRI® incubator?

Answer: The obvious advantage is that it can be utilized by small-scale IVF clinics (those with limited space) without compromising the quality and function expected of an IVF incubator.

Question: What is the difference between a dry and a humidity incubator?

Answer: The difference lies on the presence and/ or absence of a water or humidity source. Dry incubators are desktop CO₂ and O₂ incubators that directly warm dishes in the chambers allowing superior temperature conditions in comparison to conventional incubators, without using any humidity source (moisture-free). Some professionals believe that presence of humidity brings about the prospect of microbial overgrowth, which can adversely alter the cultured embryo’s development.

On the other side of the spectrum, some studies would claim that humidification during incubation increases the rate of blastocyst formation, and eventually, pregnancy rate. In a humidity incubator like the Mini MIRI® Humidity, a water bottle is located on the side of the unit for refilling and easy control of water level. All other features are similar with that of a Mini MIRI® Dry incubator.

The in vivo state is moist, and imitating this in vitro appears to be physiologically correct. Yet, there is no collective settlement among scientists (IVF professionals) with regards to the advantages of dry against humid incubators.

Esco Medical offers a wide array of IVF devices that caters the industry’s specific needs. Aside from its MIRI® Multiroom incubators, MIRI® Time-Lapse incubator, Esco Medical also manufacture incubators with smaller footprint like the Mini MIRI® Dry and Humidity.