Fertility

Question 1

What is lactational amenorrhoea?

Answer 1

Infertility in lactation

Question 2

What causes lactational amenorrhoea?

Answer 2

Hyperprolactinaemia, PRL also inhibits the reproductive system at the level of the gonads and pituitary by disrupting the pulsatile release of GnRH

Question 3

Why can dopamine antagonists cause infertility?

Answer 3

Dopamine inhibits PRL secretion - loss of inhibition - hyperprolactinaemia

Question 4

How frequently must breastfeeding occur for effective lactation amenorrhoea?

Answer 4

4hly feeds; 98% effective in first 6 months

Question 5

What is the role of contraception at the level of the brain and pituitary?

Answer 5

Inhibit FSH & LH by enhancing negative feedback; varieties of oral contraceptive pill. Use of synthetic oestrogens, progestogens

Question 6

How does the combined pill work?

Answer 6

Prevents ovulation by action at pituitary

Thickens cervical mucus to block sperm entry

Taken for 21 days with 7 day break

Question 7

How does the progesterone only pill work?

Answer 7

Thickens cervical mucus

Weaker effect to prevent ovulation

Question 8

What do emergency contraceptive pills contain? How do they act?

Answer 8

High dose of a synthetic progesterone receptor modulator (levonorgestrel) (or previously, a synthetic oestrogen) within 72 hours of unprotected intercourse (can be a combined dose).

The high dose oestrogen was thought to act by speeding movement of the conceptus through the fallopian tube to reach an unprepared uterus – it has now been superseded.

The progesterone receptor modulator levonorgestrel (progesterone-like) is believed to act either by preventing ovulation and/or by thickening cervical mucus to reduce/prevent sperm entry

Question 9

What contraception options work at the level of the uterus?

Answer 9

Intrauterine devices (IUDs): typically copper (affects uterine environment)

Intrauterine systems (IUSs): carries progesterone receptor modulator Use IUSs as a ‘morning-after’ device containing progesterone receptor modulator

Question 10

What contraception works at the level of the fallopian tube?

Answer 10

Sterilization

Cut or tie the fallopian tubes

Reversible but with risk of infertility

Question 11

What contraception methods work at the level of the vagina?

Answer 11

Female condom

Post-coital douches

Cervical cap - ~95% effective

Vaginal ring impregnated with progesterone receptor modulator

Question 12

How can fertility problems be diagnosed?

Answer 12

Use GnRH to test pituitary function; kisspeptin to test its receptors

Question 13

How can GnRH be used for fertility treatment? (two different ways)

Answer 13

Agonists: Pulsed GnRH to restore fertility in Kallman’s females (GnRH secreting neurons do not migrate normally in development)

Long-acting GnRH to stop gonadotrophin secretion and thereby synchronize cycles for IVF

Question 14

How can males fertility by treated hormonally?

Answer 14

Use FSH and LH to enhance

Question 15

Why is testosterone not appropriate to help male fertility?

Answer 15

Dose needed is too high

Question 16

What is ROSI?

Answer 16

Round spermatid injection - In the ROSI method, since there are no mature sperm cells in the semen, IVF cannot be performed. The round cells extracted from the tissue obtained by biopsy are introduced into the oocyte.

Question 17

What is ICSI?

Answer 17

Insertion of a single spermatozoon into an oocyte in vitro

Question 18

What is IVF?

Answer 18

Self-employed penetration of sperm into an egg after addition of sperm in vitro

Question 19

How can infertility in females be detected? (3 ways)

Answer 19

Use of FSH and LH assays to detect cause of infertility, may suggest poor corpus luteum formation if in conjunction with effects on progesterone levels

Measure circulating antiMullerian hormone – secreted by primary follicles – indicates follicles remaining

Scan ovaries - ultrasound

Question 20

Uterus fertility assistance includes

Answer 20

Correction of any adverse condition by surgery

Question 21

Fallopian tube fertility includes

Answer 21

Semen can be introduced into vagina or uterus

GIFT – Gamete Intra-Fallopian Tube injection

ZIFT – Zygote Intra-Fallopian Tube injection (now largely superseded by IVF methods)

Question 22

What is the first step of IVF

Answer 22

Use of GnRH analogues to block LH surge (initially non-pulsatile agonist, now antagonist) to synchronize cycle

Question 23

How is the follicle stimulated (IVF)?

Answer 23

Use of FSH & LH, and/or clomiphene (oestrogen receptor modulator) to stimulate follicle formation/ripening (superovulate) for IVF

Question 24

How is the egg harvested (IVF)?

Answer 24

Egg collection under ultrasound guidance

Question 25

Once the egg is harvested what happens (IVF)?

Answer 25

Follicle storage and culture; also in vitro maturation of oocytes

Fertilize the oocyte and transfer several embryos to the uterus in the hope that one will implant.