Beyond Earth's bounds: navigating the frontiers of Assisted Reproductive Technologies (ART) in space

Abstract

As interest in deep space travel grows exponentially, understanding human adaptation in becoming an interplanetary species is crucial. This includes the prospect of reproduction. This review summarizes recent updates and innovations in assisted reproductive technologies (ART) on Earth, while also discussing current challenges and areas for improvement in adapting ART studies to the space environment. We discuss the critical components of ART - gamete handling and preparation, fertilization, embryo culture, and cryopreservation - from the daily practice perspective of clinical embryologists and reproductive endocrinologists and lay out the complicated path ahead.In vitro embryo development in low Earth orbit and beyond remains questionable due to synergetic effects of microgravity and radiation-induced damage observed in simulated and actual in-space mammalian studies. Cryopreservation and long-term storage of frozen samples face substantial obstacles - temperature limitations, lack of trained personnel, and absence of adapted cosmic engineering options. We touch on recent innovations, which may offer potential solutions, such as microfluidic devices and automated systems. Lastly, we stress the necessity for intensive studies and the importance of an interdisciplinary approach to address numerous practical challenges in advancing reproductive medicine in space, with possible implications for both space exploration and terrestrial fertility treatments.

Keywords: Assisted Reproductive technologies (ART); Embryo; In Vitro fertilization (IVF); Microgravity; Oocyte; Spaceflight; Spermatozoa.

Fig. 1

Schematic representation of the main steps of IVF

Fig. 2

The denudation devices proposed by: (A) Zeringue et al. (2001) and (B) Weng et al. (2018) (A) Device created from polydimethylsiloxane with channels of oocyte-cumulus complex size (400 μm) is implemented for tracking and denudation of the oocytes. Two narrow regions of the microchip reorient the cumulus into a doughnut shape, while two ports (channels significantly narrower than the ovum) are used to remove the cumulus. The device uses pressure-driven flow to properly position and denude the oocytes. (B) The microfluidic device implicates denudation of enzyme-treated cumulus–oocyte complexes by flow-guided passage through a series of jagged-surface constriction microchannels of optimized geometries. The jagged inner wall of the channels is stripping off cumulus–corona cell mass. Reprint with permission from “Automation in Clinical Embryology Laboratories – What is Next?” by Halicigil C., Ogut M.G., Demirci U. © 2023, World Scientific

Fig. 3

Integration of fertilization and development in a microwell array proposed by Han et al. (2010). Reprint with permission from “Automation in Clinical Embryology Laboratories – What is Next?” by Halicigil C., Ogut M.G., Demirci U. © 2023, World Scientific