An experiment conducted on board the International Space Station might help to clarify the science of pregnancy in space. A study published earlier this month in the journal Stem Cell Reports involved studying what the authors describe as "cryopreserved mouse spermatogonial stem cells" that spent six months on the ISS. The scientists studying the mouse stem cells found that, after six months, that time spent in space "did not increase apoptosis or DNA damage" in the cells.