players in the female reproductive cycle other pituitary gland
0:04the ovaries and the uterus their activities are closely coordinated
0:09each month 10 other over Eve releases a single egg
0:14an event known as ovulation it is brought about by a series of complex
0:19interactions between the pituitary gland
0:22the ovaries and the usurious the bridge your treat land
0:26is itself under the control of this small area of the brain
0:30known as the hypothalamic its a new menstrual cycle begins
0:35when the nerve cells of this center secreto hormone called
0:39go another Trojan releasing hormone GnRH
0:43into the network the blood vessels which surrounds the pituitary gland
0:49stimulated by pulses Afghan at a church in releasing hormone
0:53sales in the pituitary gland secretion other hormone
0:57follicle stimulating hormone or if is
1:00H
1:03FSH travels in the bloodstream reaching the ovaries
1:07there it stimulates the formation and growth
1:10up an ovarian follicle in one or hungry
1:14the follicle consists of an egg a number of surrounding cells which secrete
1:19East region Homans and fluid if a stage help see eg to mature
1:24and prepares it for release as the follicle matures
1:28the hypothalamic increases secretion of GnRH
1:33this in turn stimulates the pituitary to secrete a second home on
1:38reject on the ovary this is Lucien icing home I'm
1:42or L H
1:46toward the middle of the cycle there's a sudden peak in the blood level
1:49love LH this act as the trigger for ovulation
1:53within minutes of its release the egg is guided by section through the fringed
1:59opening up the outer end up the fellow P in to YouTube
2:02starting at on a journey which will take five or six days
2:06as it passes down the cute and finally reaches the cavity if the uterus
2:10meanwhile after the follicle ruptures
2:13it is converted into this yellowish body known as the corpus luteum
2:18cells at the corpus luteum secrete the hormone progesterone
2:22which brings about important changes in the lining of the uterus
2:26preparing it for possible pregnancy in fact
2:29the lining of the uterus known as the endometrium
2:32undergoes changes in response to hormone levels during the cycle
2:37in the first half for the cycle known as the follicular phase
2:42the developing follicles sea creature increasing amount to the east Region
2:45home I'm
2:46which encourages regeneration of the endometrium
2:51after a population that there are important changes
2:54in the endometrium aimed at making it suitable to receive a fertilized egg
2:59these changes are brought about by a secretion a progesterone
3:03from the corpus luteum
3:06the secretion a progesterone is maintained for several days
3:10but if he is not fertilized in that time
3:13the corpus luteum withers and falling levels are progesterone and
3:18East region trigger the shedding of the uterine lining as the menstrual flow
3:22the cyclin starts again
3:27but if the egg is fertilized no menstruation occurs
3:31as the corpus luteum continues to function
3:34see Creating progesterone during the first three months of the pregnancy
3:39thereafter numerous changes occurred to support the developing embryo