00:01
Which process is responsible for causing the menstruation, which also known as the period.
00:06
So if we look at the menstrual cycle, so fsh and lh, they will peak and then trigger ovulation, which means the release of egg, usually one, sometimes it can have more.
00:43
Now when the egg is being released, the ruptured follicle that used to contain the egg actually transform into a structure called corpus luteum.
01:17
So this corpus luteum structure actually temporarily during this period secretes a hormone, mainly progesterone.
01:27
So this prepares uterus for potential pregnancy because you never know if the egg is going to be fertilized.
01:48
So progesterone is the hormone that caused the uterine lining to be thickened.
02:07
Again, the progesterone is being secreted to prepare the uterine lining for possible or potential pregnancy.
02:16
So during the uterine lining thickening, all the blood vessels and everything grows inside of the linings.
02:24
Now from there, you have two different pathways.
02:28
If there is a fertilization of the egg, which means the egg is going to become an embryo implant into the uterus, then the embryo is going to produce the hcg hormone, which will actually maintain the corpus luteum and the corpus luteum is going to continue to produce progesterone.
02:50
However, if there's no pregnancy, there's no fertilization, then no hcg is going to keep the corpus luteum there.
03:00
So the corpus luteum actually break down...