The real-time biolochemical millieu of the devloping placenta is completely unknown. Sensors exist to sample microscopic changes in bioactive compounds in the atmosphere (for environmental health), and small biosensors have been developed to monitor hormonal and biochemical activity in tumors, for example. While not performed in every pregnancy, chorionic villus sampling is performed during pregnancy (removal of placental tissue with pregnancy ongoing. Why not test (perhaps in a non-human primate model) whether a microscopic placental biosensor is feasible for pregnancy monitoring and discovery? While this is certainly a technology for the future, and safety and efficacy would need to be tested prior to ever considering use in humans, this technology may lead to ways to better understand the earliest placental development without having to interrupt pregnancy, sacrifice an animal or perform analyses that depend solely on surrogate placental markers.