L8 - Fertility Control

Question 1

HORMONAL CONTRACEPTION

i) what effect does oestrogen from the ovary normally have on GnRH release from the HT?
ii) which hormone levels does hormonal contracep increase? what effect does this have on LH and FSH and therefore stimulation of developing follicles?

Answer 1

i) normally oestrogen feeds back to the hypothalamus to decrease GnRH release and therefore LH and FSH

ii) hormonal contraception increases oestrogen and progesterone levels
- this decreases LH and FSH levels by neg feedback
- low LH and FSH decreases stimulation of developing follicles and decreases likelihood of implantation if an egg is fertilised

Question 2

COMBINED HORMONAL CONTRACEPTIVES

i) name three ways it can be given
ii) what is the failure rate if used perfectly?
iii) name three things that can contribute to contraceptive failure

Answer 2

i) oral, transdermal and vaginal ring
ii) 1% fail rate with perfect use
iii) malabsorption due to D&v, drug interactions and a persons weight

Question 3

BENEFITS AND RISKS OF CHC

i) name three cancers that it reduces the risk of?
ii) name two conditions it can be used for the management of
iii) how can it affect bone density?
iv) what is the main risk of the CHC?
v) which two cancers may it increase risk of?

Answer 3

i) endometrial, colorectal and ovarian cancer
ii) mx of PCOS and endometriosis
iii) can maintain bone density for peri menopausal females under 50
iv) main risk is VTE - 3 to 3.5 fold increase
v) increased risk of breast and cervical cancer (still small)

Question 4

ORAL PROGESTERONE ONLY CONTRACEPTIVE

i) how does it affect cervical mucus? what does this prevent?
ii) what is the primary mech of action of oral desogestrel only preparations
iii) when may they be a suitable alternative?

Answer 4

i) alters cervical mucus to prevent sperm penetration (can also inhibit ovulation)
ii) primary mech for desogestrol is inhibiting ovulation
iii) suitable alternative if oestrogen is contraindicated eg high risk of thrombosis (stroke, MI, diabetes)

Question 5

PARENTERAL PROGESTERONE ONLY CONTRACEPTION

i) how long is its action?
ii) what happens to fertility return after discontinuation?
iii) how long does norethiserone provide contraception for? what can it be used for?
iv) which contraceptive method can offer 3 years protection?

Answer 5

i) prolonged
ii) delayed return of fertility but no evidence of infertility
iii) 8 weeks - can be used as a short term interim eg before vasectomy is effective
iv) nexplanon implant (etonogestrel releasing)

Question 6

IUD PROGESTERONE ONLY

i) which hormone is released direct to uterine cavity?
ii) which two things can it be used for?
iii) what three effects does it have?
iv) how quickly does fertility return?
v) name two advantages it has over the copper IUD

Answer 6

i) levonorgestrel
ii) contraception and menorrhagia (heavy bleeding)
iii) prevents endometrial prolif, thickens cervical mucus and can supress ovulation
iv) fertility returns quickly after removal
v) improves dysmennorhea (period pain), reduces blood loss and can reduce PID

Question 7

EMERGENCY CONTRACEPTION

i) which hormone is often used? which other non hormonal method can be used?
ii) which hormone is effective for 72 hours post intercourse?
iii) which is effective for 120 (5days) post intercourse?
iv) what may reduce effectiveness? which hormone is particularly implicated? what should be given instead?
v) what is first line emergency contraception for a woman that had intercourse 90-120 hours ago?

Answer 7

i) levonogestrel or ulipristal acetate
- can also use a copper IUD

ii) levonogestrel is effective up to 72hrs
iii) ulipristal acetate is effective for 120 hours
iv) high BMI may decrease effectiveness of levonogestrel therefore if BMI is over 26 give ulipristal acetate (or double dose levonogestrel)
v) first line for 90-120 hours is ulipristal acetate

Question 8

MALE HORMONES AND CONTRACEPTION

i) what effect does high testosterone levels have on GnRH release? what effect does this ultimately have on sperm production
ii) what could be used as a male contraceptive? give both a single and combined example
iii) name three side effects each of these could have

Answer 8

i) high testos = reduced GnRH release therefore reduced FSH therefore less sperm prod
ii) testosterone only or testosterone + progesterone

iii) testos SEs = acne, altered libido, inc weight
adding proges minimises testos side effects
- proges = androgenic side effects eg weight gain, acne or decreased HDL