List hormones involved in the menstrual cycle

1.List hormones involved in the menstrual cycle
2.Describe the endometrial changes that occur during menstruation
3.Describe the methods of determination of ovulation
4.Explain the physiological basis for the use of oral combined contraceptive pill







1..List hormones involved in the menstrual cycle



2. Describe the endometrial changes that occur during menstruation


There are three phases in endometrium in menstrual cycle

1. Proliferative phase
2. secretory phase
3. Menstrual phase

Proliferative phase (pre - ovulatory phase, follicular phase )

Proliferative phase start at the end of menstrual flow under influence of estrogen. In this period new endometriam is formed and endometrium increase it thickness rapidly. Uterine glands are lengthen . This phase last form 5th day of menstrual cycle to 14th day of menstrual cycle.

Secretory phase ( luteal phase )

This phase start after ovulation and it is maintained by progesterone secreted by corpus luteum . In this phase endometrium become highly vascularizied and lightly oedematous .Glands become coiled and tortus and they started to secreate clear fluids.

Menstrual phase

This phase start at the end of secretory phase and it usually last form 1st day of cycle to 5th day of cycle. In this phase endometrium become thinner due to withradwal of hormonal support by corpus luteum, The blood vessels become highly coiled, blood stagnates, and the cells get necrosed due to unavailability of blood. Then this necroesd endometrial tissue shed and pass out through vagina. During this period, the functionalis is completely shed.



3.Describe the methods of determination of ovulation

Basal body temperature method

Normally there is variation of temperature of body during menstruation. Following ovulation (24 hours after ovulation) there is mild elevation of body temperature (0.5 C0 – 1 C0) due to thermogenic effect of progesterone. Raised temperature is sustained throughout the second half of the cycle and fall 2-3 days prior to next cycle. In addition to that there is slight fall in temperature at the ovulation but it is difficult to detect. 
Body temperature measures from the day one of the menstrual cycle by ideally using fertility thermometer and chart it. women should measure her oral temperature each day morning after getting up form bed without washing mouth or having tea ect… . if there is raised temperature in second half of the cycle, ovulation has occurred .






Measurement of progesterone level (Hormonal method )

Serum progesterone level performed approximately seven days before the predicted date of a menstrual period (day 1). If women has 28 days cycle, test performed on day 21.elevated level of progesterone (above 20-25nmol) confirms ovulation occurred in that cycle  


Cervical mucus stretch test   ( Spinnbarkeit test   )

The cervical mucus is produced by the cervix and changes consistency  throughout menstrual cycle under influence of estrogen and progesterone.estrogen makes the mucus thinner and more alkaline.under influence of progestarone cervical mucus become thick,tenacious and more cellular. at the time of ovulation cervical mucus are thinnest and it elasticity increase ( spinnbarkeit ). therefor when strech drop of cervical mucus it can be stretch into long   Disappearance of fern pattern of cervial mucus also aused to determine ovulation 



4.Explain the physiological basis for the use of oral combined contraceptive pill
During normal menstrual cycle hypothalamus secretes GnRH and stimulate pituitary to secrete FSH and LH .FSH act on ovary and cause maturation of follicle. These follicles secrete estrogen which act on hypothalamus and pituitary and inhibit release of GnRH and FSH and LH (negative feedback mechanism). At about 14 day of cycle ,due to LH surge ovulation occur . Following ovulation, corpus luteum produced progesterone and maintain secretory phase of endometrium .These progesterone act on hypothalamus inhibit it ( negative feedback Mechanism ) .


Oral combine contraceptive pill contain high level of estrogen and progesterone. This hormone act on hypothalamus and decreases the pulse frequency of GnRH. Therefore decreases the release of FSH and LH . Decrease level of FSH inhibit development of follicle and absence of LH surge result anovulation . Secretory phase of endometrium is maintained by progesterone which is in the oral contraceptive in the absence of corpus luteum . After 21 days menstruation occur due to absence of hormonal pill. After 21 days pill contain iron which gives iron which is lost during menstruation 




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