What is menstrual
cycle? Which hormones regulate menstrual cycle?
What is menstrual cycle? Which hormones regulate menstrual cycle?
The menstrual cycle is
a series of cyclic physiologic changes that take place inside the
female reproductive tract in primates. The whole cycle takes around
28 days to complete. The end of the cycle is accompanied by the
breakdown of uterine endothelium, which gets released in the form of
blood and mucous through the vagina. This is known as menses.
The follicle
stimulating hormone (FSH), luteinizing hormone (LH), estrogen, and
progesterone are the various hormones that regulate the menstrual
cycle. The level of FSH and LH secreted from the anterior pituitary
gland increases during the follicular phase. FSH secreted under the
influence of RH (releasing hormone) from the hypothalamus stimulates
the conversion of a primary follicle into a graafian follicle. The
level of LH increases gradually leading to the growth of follicle and
secretion of estrogen. Estrogen inhibits the secretion of FSH and
stimulates the secretion of luteinizing hormone. It also causes the
thickening of the uterine endometrium. The increased level of LH
causes the rupturing of the graafian follicle and release the ovum
into the fallopian tube. The ruptured graafian follicle changes to
corpus luteum and starts secreting progesterone hormone during the
luteal phase. Progesterone hormone helps in the maintenance and
preparation of endometrium for the implantation of the embryo. High
levels of progesterone hormone in the blood decrease the secretion of
LH and FSH, therefore inhibiting further ovulation.
The menstrual cycle is a series of cyclic physiologic changes that take place inside the female reproductive tract in primates. The whole cycle takes around 28 days to complete. The end of the cycle is accompanied by the breakdown of uterine endothelium, which gets released in the form of blood and mucous through the vagina. This is known as menses.
The follicle stimulating hormone (FSH), luteinizing hormone (LH), estrogen, and progesterone are the various hormones that regulate the menstrual cycle. The level of FSH and LH secreted from the anterior pituitary gland increases during the follicular phase. FSH secreted under the influence of RH (releasing hormone) from the hypothalamus stimulates the conversion of a primary follicle into a graafian follicle. The level of LH increases gradually leading to the growth of follicle and secretion of estrogen. Estrogen inhibits the secretion of FSH and stimulates the secretion of luteinizing hormone. It also causes the thickening of the uterine endometrium. The increased level of LH causes the rupturing of the graafian follicle and release the ovum into the fallopian tube. The ruptured graafian follicle changes to corpus luteum and starts secreting progesterone hormone during the luteal phase. Progesterone hormone helps in the maintenance and preparation of endometrium for the implantation of the embryo. High levels of progesterone hormone in the blood decrease the secretion of LH and FSH, therefore inhibiting further ovulation.
