from The Century Dictionary and Cyclopedia
- Prior to the formation of a placenta; previous to the establishment of placental connection between the fetus and the parent.
Sorry, no etymologies found.
Other tests, such as amniocentesis and chorionic villus sampling, involve drawing fetal cells from amniotic fluid or preplacental tissue and checking them for chromosomal defects.
"In addition to nutrients and oxygen ... pollutants can readily cross the preplacental structures and potentially impact embryonic development," lead author Tong Zhu at the State Key Joint Laboratory for Environmental Simulation and Pollution Control in Beijing University told Reuters in an email.