Blastocyst formation and pregnancy rate comparison between standard large box (Sanyo) incubators and a novel Geri® time-lapse incubator

Abstract

Objective We compared the blastulation rates and pregnancy success from embryos cultured in standard “large box” Sanyo incubators and the Geri® time-lapse incubator. Design A retrospective study in a private IVF laboratory. Materials and Methods Mature oocytes were fertilized by either conventional insemination or ICSI and cultured to the blastocyst stage undisturbed in Continuous Single Culture®-NX (Irvine Scientific) at 37°C in 6% CO2. Patients could self-elect to be included in the Geri incubator prior to retrieval. Availability for the Geri was limited to six culture chambers. Patients with a minimum of one mature oocyte with normal fertilization were eligible to have their embryos cultured in the Geri. All embryos were either biopsied and/or frozen on Day 5, 6 or 7 of development. Results The evaluation was performed over a six-month period (August 2018-February 2019). A total of 67 patients had their embryos cultured in the Geri. A total of 611 zygotes were cultured to the blastocyst stage, resulting in 247 blastocysts – a 40.4% blastulation rate. In comparison, 288 patients yielded 2,387 zygotes that were cultured in the Sanyo incubators, resulting in 1,055 blastocysts a 44.2% blastulation rate. Chi-square analysis showed no significant difference in blastulation rates (p=0.0932) between incubator types. In addition, 279 frozen embryo transfers (16 Geri and 264 control) were performed with no significant difference (p=0.9556) in pregnancy success, 33% and 34%, respectively. Pregnancy success was identified by positive fetal cardiac activity at seven weeks gestation. Time-lapse morphokinetic assessment was not applied during this evaluation period. Conclusions In the IVF laboratory, several types of incubators are available, and each requires careful consideration. The Geri, an independent chamber/microscope incubator, offers a safe environment for embryo culture with minimal disturbance. Blastulation rates did not differ when compared to the large box incubators, allowing for another option for embryo culture. The Geri has six chambers, which can accommodate a maximum of 16 embryos per Geri Dish, which may be limiting factor to some laboratories. However, the Geri Dish is unique in that it allows for potential benefits of group culture while maintaining individual embryo growth tracking. The ability to assess the embryos in real time does provide opportunities for clinical applications for embryo selection. We are continuing to monitor pregnancies and embryo culture outcomes accordingly. Disclosures EMD Serono provided the incubator at no cost during the embryo evaluation period. Funding None