In a groundbreaking experiment conducted in 2021 on the International Space Station (ISS), mouse embryos have been shown to reach an early stage of development despite the challenges of space conditions. Thawed from frozen two-cell embryos, a significant number developed into healthy clusters of cells known as blastocysts upon their return to Earth. The study, published in iScience on October 27, suggests that the radiation and weightlessness of space may not be immediate impediments to mammalian reproduction. While blastocysts are only one phase of the reproductive and developmental process, the successful growth of mouse embryos in space marks a crucial step in understanding the potential effects of space conditions on human reproduction. This experiment, led by biologist Teruhiko Wakayama and his team from the University of Yamanashi in Kofu, Japan, involved launching two-cell embryos to the ISS in a specially designed device. Out of 360 samples, 72 survived the journey, and 17 developed into normal blastocysts. The undamaged cells underwent successful multiplication, taking on identities as precursors of fetal tissue or the placenta. Although blastocysts have limited viability outside of uteruses, the short-term experiment provided valuable insights. Future experiments aim to implant viable embryonic cells from space experiments in mice to observe their development over a more extended period. Researchers are particularly interested in exploring the impact of microgravity on the positioning of different cells within a blastocyst. While the initial study showed promising results with three-quarters of fetal precursors settling in the correct location, further research is needed to fully comprehend the effects of microgravity on developing cells.