I've been searching for this info for a while.
The syncytiotrophoblast is the outermost layer of the fertilized cells and is thicker and in contact with uterine spaces. It becomes a syncitium (layer of nuclei and cytoplasm without lateral cell borders) and is termed the "syncytiotrophoblast".
Wikipedia confirms it (if you trust Wikipedia as a source)
Implantation stages:The syncytiotrophoblast secretes progesterone in addition to human chorionic gonadotropin (hCG) and human placental lactogen (HPL); hCG prevents degeneration of the corpus luteum.
Very interesting! Thanks for posting that. The term Chemical Pregnancy to me has always bothered me greatly because of this!! How can we have HCG without implantation?? This sort of helps to explain it though.
Do a search for "early pregnancy factor." My million dollar idea involves designing a cheap, accurate test for EPF. Women could know within 48 hours if fertilization had occurred. Of course that wouldn't tell you if implantation would occur, but wouldn't you buy a test that could tell you your chances of pregnancy were much higher that cycle?
That was very interesting.......I wonder what is going on in there...With my son I knew the exact date when he implanted..I felt it around the same time for 2 days...it was like the egg was nestling in the uterine wall.... so that information confirms what i was feeling....