胚胎在子宫内的附植 ZP ICM 滋养层 uterine epithelium str oma sey.- 1- shedding of ZP 2. pre-contact 3. Apposition 4. Adhesion blastocyst cellular contacts orientation 5· penetration of e EPITHELIOCHORIAL placent 止皮绒毛膜胎盘 ENDOTHELIO or HAEMOCHORIAL placenta内皮绒毛膜胎盘胚胎在子宫内的附植 ZP 上皮绒毛膜胎盘 内皮绒毛膜胎盘 ICM 滋养层