noun
placentation
Biological term for the formation and structure of the placenta in mammals.
胎盤形成の異常は妊娠合併症の原因となることがある。
Abnormal placentation can cause pregnancy complications.
胎盤 means 'placenta', while 胎盤形成 refers specifically to the process or formation of the placenta.
Compound of 胎盤 (placenta) and 形成 (formation).