00:01
What is the role of progesterone? so progesterone is also a hormone that relates to the reproductive system.
00:16
So first of all, the main role obviously is, or primary role is to regulate the menstrual cycle just like the estrogen.
00:24
So during the menstrual cycle, progesterone level rises in the second half of the cycle during luteal phase after ovulation.
00:32
The corpus luteum produces progesterone and it actually causes endometrium, the inner lining of uterus to thicken and proliferate.
01:20
This will actually get ready for the embryo to implant if fertilization ever occurs.
01:30
So prepare for potential embryo implantation.
01:55
Now this depends on whether the egg is being fertilized.
01:59
If no fertilization occurs, the corpus luteum will break down and estrogen level will go back down.
02:07
The low estrogen level will cause endometrium to break down and this will lead to the menstrual bleeding or menstrual flow.
02:16
Now, if the pregnancy happens, occurs, then the corpus luteum will continue to produce progesterone to support pregnancy.
02:28
So this will continue to support pregnancy until the placenta develops during about week 10, and then placenta is going to produce the progesterone continuously to support the embryo growth until birth.
02:46
So second, let's say if no fertilization, progesterone level goes down because corpus rudum breakdown...