men's and women's health: oral contraceptions

Question 1

MOA of prosgestogenic component

Answer 1

◦ Inhibits FSH and LH production
◦ Blocks mid-cycle LH surge responsible for ovulation
◦ Thickens cervical mucus, affecting sperm penetration
◦ Slows tubal motility, delaying sperm transport
◦ Induces endometrial atrophy to prevent implantation

Question 2

pharmacology of progestogenic component

Answer 2

preganes, estranes, gonanes, spironolactone derivative

Question 3

moa of estrogenic component

Answer 3

◦ Semisynthetic estrogen ➔ estrogen receptor agonist
◦ Effect on hypothalamus to inhibit GnRH production
◦ Effect on pituitary gland to inhibit FSH and LH secretion
◦ Overall effect to inhibit ovulation

Regulates bleeding and prevents irregular shedding of
endometrium

Question 4

factors favoring lower doses of EE (20-25mcg)

Answer 4

◦ Adolescence
◦ Underweight (< 50 kg)
◦ Age > 35 years
◦ Perimenopausal
◦ Fewer side effects such as nausea/vomiting, breast tenderness, weight
gain

Question 5

factors favoring higher doses of EE (30-35mcg)

Answer 5

◦ Obesity or weight > 70.5 kg
◦ Breakthrough bleeding/spotting

Question 6

Diane-35, Estelle-35

Answer 6

cyproterone acetate 2mg + EE
- should not be prescribed for the purpose of contraception alone, due to risk of VTE
- indicated for treatment of moderate to severe acne related to androgen-sensitivity and/or mild forms of hirsutism in women of reproductive age

Question 7

Yasmin

Answer 7

drosperinone

Question 8

Qlaira

Answer 8

4-phase OC: estradiol valerate and dienogest

Question 9

estrogenic SE

Answer 9

Nausea, vomiting, bloating, decreased libido, cyclic weight gain due to fluid retention, breast
tenderness, breakthrough bleeding, irritability, headache, hypertension, increase triglyceride levels

Question 10

progestogenic SE

Answer 10

Breast tenderness, headache, hypertension, depression, lethargy, fatigue, decrease in libido,increase
in appetite, increase LDL and total cholesterol levels

Question 11

androgenic SE

Answer 11

Acne, increased appetite and weight gain, hirsutism, fatigue, depression, increase in libido, oily skin
and scalp

Question 12

Factors favoring choice of monophasic products

Answer 12

◦ Late-cycle bleeding
◦ Less confusion and less complicated missed-dose instructions

Question 13

Factors favoring choice of multi-phasic products

Answer 13

◦ Lower total monthly dose of progestin while providing adequate
endometrial support and contraception
◦ Reduction in progestin-related side effects
◦ Possibly useful in women who have cardiovascular disease or
metabolic abnormalities

Question 14

adv of COCs

Answer 14

• relatively inexpensive
• easily reversible
• non-contraceptive benefits:
  > thin the endometrial lining over time, hence reduced menstrual flow and uterine contractions
  > cycle control
  > improvement in acne and hirsutism
  > 2nd line treatment of PMS and PMDD
  > decr risk of endometrial cancer and ovarian cancer
  > improvement in BMD in older women (estrogen inhibits bone resorption by acting on osteoclasts)

Question 15

drug interactions with enzyme inducers reducing EE and progestin levels

Answer 15

anti-retrovirals
anti-epileptics
rifampicin

Question 16

ddi with abx

Answer 16

entero-hepatic recycling of EE

Question 17

c/i for COCs

Answer 17

• breastfeeding <6weeks post partum
• age>35yo and smoking >15sticks/day
• elevated BP with SBP>160 and DBP>100 with end organ vascular disease or smoking
• uncontrolled dyslipidemia and additional risk factors (CAD, DM, HTN, smoking, pos FHx)
• diabetic women with vascular disease ep nephropathy, retinopathy, neuropathy, or other vascular disease or dm more than 20 years duration
• Hx of DVT/PE, acute DVT/PE and pt w DVT/PE on anticoagulant therapy
• current and hx of IHD
• Hx of stroke
• Migraine>35yo w.o aura or migraine with aura at any age
• current breast cancer

Question 18

Micronor

Answer 18

POP: norethisterone 0.35mg
- low dose progesterone

generally used in situations whereby estrogen is c/i or not recommended eg. lactation, current DVT, migraine
c/i, current breast cancer

Question 19

micronor moa

Answer 19

• prevention of ovulation in about half of cycles
• lowering the mid-cycle LH and FSH peaks
• slowing the movement of ovum through the fallopian tubes
• thickening the cervical mucus to prevent sperm penetration
• alteration of the endometrium, making it unfavourable to implantations

Question 20

cerazette

Answer 20

desogestrel 75mcg

effectiveness comparable to COCs

common SE: irregular bleeding (most common), acne, nausea, headache, mood swings

c/i, current breast cancer

Question 21

micronor and cerazette: missed dose

Answer 21

micronor: 3hr leeway for missed pills
cerazette: 12hr leeway for missed pills, due to its effect on ovulation inhibitions

Question 22

cerazette moa

Answer 22

inhibition of ovulation in 97% of cycles

Question 23

indications for emergency contraceptive

Answer 23

• unprotected intercourse within 72-120hrs
• condom accident
• misused contraceptive method (eg. missed pills, contraceptive patch fell off)
• sexual assault
• exposure to teratogen

effectiveness: 57-85%, meant only for occasional use

Question 24

Yuzpe method

Answer 24

combined regimen for hormonal EC:
- 2 doses each containing 100mcg of EE
- 0.5mg of LNG taken 12hrs apart

Question 25

Postinor-2

Answer 25

progestin-only method
- 2 tablets of levonorgestrel taken 12 hours apart
- or stat dose of 1.5mg LNG as effective

Question 26

is yuzpe method or progestin-only regimen more effective?

Answer 26

progrestin-only, more effective and less SE (N/v)

Question 27

moa of hormonal EC

Answer 27

possible mechanism:
- inhibit or delay ovulation by neg feedback on hypothalamus, reducing FSH and LH secretion
- alter receptiveness of endometrium and inhibit implantation
- thicken cervical mucus to interfere with sperm transport or penetration
- impairment of corpus luteum function

Question 28

what if patient vomits after taking 1 pill of EC?

Answer 28

dose should be repeated if vomiting occurs within 2 hours of taking a dose

Question 29

SE of hormonal EC

Answer 29

• n/v
• irregular bleeding: menstrual period usually occurs within 1 week before or after expected time, irregular spotting also reported but resolved without tx
• breast tenderness
• abdominal pain
• dizziness
• headache
• fatigue

Question 30

Ella

Answer 30

30mg ulipristal acetate
- indicated for up to 120hrs of unprotected sex or contraceptive failure
- selective progresterone receptor modulator
- strong affinity for progresterone receptor, low affinity for androgen receptor, no affinity for estrogen receptor

Question 31

moa of upa

Answer 31

Inhibition or delay of ovulation
- postpones follicular ruptupre by 5-9 days hen taken at the time of LH surge
- inhibits maturation of ovarian follicles when taken in mid-follicular phase
- alters endometrial thickness when taken during early luteal phase

Question 32

UPA vs LNG: which is more effective

Answer 32

UPA is at least as effective as levonorgestrel and has similar SE profile

Question 33

EC concerns: when to seek medical advice?

Answer 33

• if menstrual period delayed by more than 1 week: suspect pregnancy
• if persistent irregular bleeding or lower abdominal pain: suspect spontaneous abortion or ectopic pregnancy

Question 34

EC effects on lactation

Answer 34

LNG: withhold breast feeding for 3 days after taking it

UPA: ‘’ 1 week

Question 35

EC effects on pregnancy

Answer 35

• will not disrupt fertilised egg after implantation has occured
• only effective before pregnancy is est
• no incr risk to an est pregnancy
• does not incr chance that subsequent pregnancy will be ectopic