O&G Menstruation

Where is gonadotrophin-releasing hormone produced? A. Hypothalamus B. Posterior pituitary C. Hypothalamus D. Adrenal glands

A

At which stage in the uterine cycle does the secretory phase occur? A. Days 1-5 B. Days 5-14 C. Days 14-28

C The secretory phase of the menstrual cycle begins after ovulation when the ruptured graafian follicle develops into the corpus luteum. The corpus luteum produces progesterone which causes the endometrium to begin secreting various substances which make the uterus more receptive to implantation of a fertilised ovum.

Which of the following are effects of increased levels of oestrogen in the follicular phase of the menstrual cycle? A. Hair thinning B. Thickening of cervical mucous C. Thinning of cercial mucous D. Thickening of endometrium

C & D In the follicular phase oestrogen functions to increase the probability of successful fertilisation. As a result, it causes the mucus of the cervix to become much thinner allowing easier passage of sperm. It also causes thickening of the endometrium to increase chances of successful implantation of a blastocyst.

Where are luteinizing hormone (LH) and follicle stimulating hormone (FSH) produced? A. Hypothalamus B. Anterior pituitary C. Posterior pituitary D. Adrenal glands

B

Which of the following symptoms indicate that a woman is about to ovulate? A. Decrease in basal body temperature B. Increase in basal body temperature C. Thickening of cervical mucous D. Thinning of cervical mucous

B and D An increase in a woman's basal body temperature occurs due to the LH surge. As a result, the rise in body temperature indicates that ovulation is likely to occur in the next 24-48 hours. The cervical mucus also becomes thinner around the time of ovulation to allow easier passage of sperm.

Which of the following are functions of progesterone? A. inhibition of oestrogen production B. inhibition of LH and FSH production C. initiation of the secretory phase of the endometrium D. Increase in the basal body temperature

B,C & D Progesterone is involved in many different processes during the menstrual cycle. It causes the endometrium to become more receptive to implantation of a fertilised ovum. It also inhibits the production of LH and FSH via negative feedback.

At which stage in the uterine cycle does the proliferative phase occur? A. Days 1-5 B. Days 5-14 C. Days 15-28

B. The proliferative phase begins immediately after the menstrual phase and involves increased levels of oestrogen driving repair and growth of the functional endometrial layer.

In a normal 28 day menstrual cycle, when would you expect the LH surge to occur? A. 8-10 B. 11-13 C. 14-16 D 17-19

B. The LH surge usually occurs on day 12. This occurs due to oestrogen levels reaching a peak level which stimulates large amounts of LH production. The high LH level causes the membrane of the Graafian follicle to become thin. As a result, 24-48 hours after the LH surge ovulation usually occurs due to the rupture of the Graafian follicle.

At which point in the menstrual cycle is a woman most fertile? A. Days 1-5 B. Days 9-16 C. Days 17-21 D. Days 22-28

B. The most fertile period of the menstrual cycle is from 5 days before ovulation to 1-2 days after. Couples often use this knowledge to increase their chances of conception.

Which one of the following is the primary source of progesterone in the later stages of pregnancy? A. Foetus B. Endometrium C. Corpus luteum D. Placenta

D The corpus luteum is the primary source of progesterone at the start of pregnancy, however, the corpus luteum breaks down eventually. So from the 8th week of pregnancy, the main source of progesterone is the placenta.

Which hormone is the corpus luteum responsible for producing? A. LH B. FSH C. Oestradiol D. Progesterone

D. The corpus luteum produces progesterone which causes the endometrium to become receptive to implantation of a blastocyst and prevents menstruation occurring.

At which stage of the uterine cycle does the menstrual phase occur? A. Days 1-5 B. Days 5-14 C. Days 14-28

A The menstrual phase occurs at the very beginning of the uterine cycle. It only occurs if no ovum is fertilised. The process begins with the breakdown of the corpus luteum which therefore ceases to produce progesterone. The loss of progesterone causes vasoconstriction of the spiral arteries supplying the functional layer of the endometrium. As a result, it becomes necrotic and is then lost through the vagina causing the 3-5 days of bleeding.

Which of the following are functions of luteinizing hormone (LH)? A. Formation and maintenance of the corpus luteum B. Thinning of the Graafian follicular membrane C. Stimulation of follicle development D. Stimulation of GnRH production

A and B

Which of the following statements are true about menstruation? A. In a normal 28 day cycle you would expect menstruation to last 3-5 days B. During menstruation the entire endometrium is shed C. During menstruation only the functional layer ofr the endometrium is shed with the basal layer remaining intact. D. Absence of menstruation is indicative of active pregnancy

A and C It is not uncommon for women to miss a period, however, it doesn't necessarily mean a woman is pregnant. It can be due to a large number of other factors such as hormonal imbalances, stress, diet, age and contraception.