Contraception Flashcards
What are the 2 forms of contraception
- Barrier method –> inhibiting viable sperm from coming into contact with a mature ovum
- Hormonal method –> preventing fertilized ovum from successfully implanting into the endometrium
What are the 4 barrier contraceptives available?
- Condoms (male)
- Condoms (female)
- Diaphragm with spermicide
- Cervical cap
Which contraceptives are useful for preventing STI transmission?
Condoms (male and female)
What are the limitations of barrier contraceptives?
High user failure rate
Benefits brought about by hormonal contraceptives
- Prevention of pregnancy
- Improvements in menstrual cycle regularity
- Management of perimenopause
- Management of PCOS
What is the MOA of progestin in COC?
- Thicken cervical mucus to prevent sperm penetration -> delaying sperm transport
- Induce endometrial atrophy (maintain thickness of endometrial and prevent it from growing)
- Stabilize the endometrial lining
- Provide cycle control
- Inhibit LH release –> prevents ovulation
What are the estrogen agents available?
- Ethinyl estradiol
- Estradiol valerate
- Esterol
- Mestranol
What is the main side effect of progestins?
- Androgenic side effects (ie. acne, oily skin, hirsutism) (associated with Gen1-3 progestins)
- Episodes of unpredictable spotting and bleeding (increases with increasing dose)
What is the MOA of Ethinyl estradiol?
- Synthetic estrogen
- Estrogen receptor agonist
- Inhibit FSH release from anterior pituitary –> suppress the development of ovarian follicle (prevent ovulation)
- Make endometrium unsuitable for implantation of the ovum
ADR of EE?
- breast tenderness
- Headahce
- Fluid retention (bloating)
- Nausea/ Vomiting or dizziness
- Weight gain
- Liver damage
- VTE
- MI/ stroke
ADR of EE?
- breast tenderness
- Headache
- Fluid retention (bloating)
- Nausea
- Dizziness
- Weight gain
- VTE
- MI/ stroke
- Liver damage
Factors favoring lower dose of EE?
- Adolescence
- underweight (< 50kg)
- Age >35 yo
- Peri-menopausal
- Fewer side effects
Factors favoring higher dose of EE?
- Obesity or weight >70.5 kg
- Early to mid-cycle breakthrough bleeding/ spotting
- Tendency to be non-compliant
List all the progestin agents by their Generation
Gen1: Norethindrone, Ethynodiol diacetate, Norgestrel, Norethindrone acetate
Gen2: Levonorgestrel
Gen3: Norgestimate, Desogestrel
Gen4: Drosperinone, Cyproterone
What are the features of Drosperinone (gen 4)?
- Analogue of spironolactone
- Anti-mineralocorticoid + some anti-androgenic action
- Less water retention and acne
- Can cause hyperkalemia, thromboembolism (VTE), and bone loss
What are the features of Cyproterone?
- Anti-androgenic + Anti-gonadotrophic
- Primary indication is to treat excessive androgen-related conditions
- Should not be used solely for contraception
- High risk for thromboembolism (VTE)
When there is early-mid-cycle breakthrough bleeding, what do you adjust in the COC?
Increase estrogen concentration
When there is late-cycle breakthrough bleeding and painful menstrual cramps, what do you adjust in the COC?
Increase progestin concentration
Advantages of monophasic COC
- Less confusing
- Less complicated miss-dosed instructions
Advantages of multiphasic COC
- Tend to have lower progestin –> less androgenic s/es
How many active and placebo pills are in conventional COC
21 days active pill + 7 days placebo (pill-free interval)
- Newer formulations has 24 active pills + 4 days placebo
Benefit of shorter pill-free interval?
- Reduce hormone fluctuations between cycles –> less side effects
How many active pills and placebo are in extended-cycle COC?
84 days active + 7 days placebo –> less periods
- Continuous COC has no placebo
What are the different methods for initiating COC and what to take note of?
- First day method: Start on first day of menstrual cycle –> no backup contraceptions required
- Sunday start method: Start on first Sunday of menstrual cycle –> require backup contraceptive for 7 days
- Quick start method: Start ASAP –> require 7 days backup contraceptive or more (until next cycle)
Factors in selecting COC?
- Hormonal content required
- Convenience
- Adherence level
- Tendency for acne, oily skin, or hirsutism
- Medical conditions (eg. premenstrual syndrome, dysmenorrhea)
Non-contraceptive benefits of COC
- Relief from menstrual related problems
- Improvement in menstrual regularity
- Better for acne
- Premenstrual dysphoric disorder (PMDD - severe PMS)
- Iron-deficient anemia
- PCOS
- Reduced risk for ovarian and endometrial cancers
- Reduced risk of ovarian cysts, ectopic pregnancy, pelvic inflammatory diseases, endometriosis, uterine fibroids, benign breast disease
Major side effects associated with COC?
- Breast cancer
- Venous Thromboembolism (VTE)
- Ischemic stroke/ MI
Risk factors for breast cancer when on COC
- Duration on COC (after discontinuation, risk return to normal)
- Age >40 yo (avoid)
- Family Hx/ risk factors for breast cancer
- Current/ recent PMH of breast cancer (within 5 years)
Which agent in COC are responsible for increasing VTE risk?
- Estrogen: Increase hepatic production of factor VII, factor X, and fibrinogen –> increase coagulation
- Newer generation progestin (Desogestrel, Drosperinone, Cyproterone)
Risk factors for VTE
- > 35 yo
- Obesity
- Smoker
- Family Hx of VTE
- Immobilization
- Cancer
Alternative contraceptives if patient is at risk of VTE?
- Low dose estrogen with older generation progestins
- Progestin-only contraceptives
- Barrier method
Which component in COC is responsible for the increased risk of MI/ ischemic stroke?
Estrogen > progestin
Which risk factor of MI/ ischemic stroke is an absolute contraindication for COC?
Migraine with aura (opt for progestin-only or barrier contraceptives)
Risk factors of MI/ ischemic stroke that requires low-dose estrogen/ progestin-only/ barrier contraceptives
- Age
- HTN
- Obesity
- Dyslipidemia
- Smoking
- Prothrombotic mutations
Absolute contraindications for COC
- Current breast cancer/ Recent Hx of breast cancer (within 5 years)
- Hx of Deep vein thrombosis/ pulmonary embolism, acute DVT/ PE and patients with DVT/ PE while on anticoagulant therapy
- Major surgery with prolonged immobilization (increased risk for VTE)
- <21 days postpartum
- Thrombogenic mutations
- Migraine with aura
- Severe HTN (SBP >160mmHg or DBP >100mmHg)
- HTN with vascular disease
- Current/ Hx of ischemic heart disease
- Cardiomyopathy
- Smoking ≥15 sticks/day AND age ≥35 yo
- Hx of cerebrovascular disease
Common adverse effects of COC use and management
- Breakthrough bleeding: If early/ mid cycle, increase estrogen; If late cycle, increase progestin
- Acne: Change to less androgenic progestin
- Bloating: Decrease estrogen/ change to progestin with mild diuretic effect (ie. Drosperinone)
- N/V: Reduce estrogen/ take pills at night
- Headache: Usually occurs in pill-free interval, switch to extended-cycle COC or continuous COC
- Menstrual cramps: Increase progestin/ switch to extended-cycle or continuous COC
- Breast tenderness/ Weight gain: Reduce estrogen and progestin
Counselling points for patient complaining about mild side effects associated with COC
- Adverse effects tend to occur during early COC use, may improve by 3rd-4th cycle after adjusting to hormone levels
- Persevere on COC for 2-3 months before considering a change
DDI with COC
- Rifampin: Antibiotic that can alter gut flora –> alter metabolism –> less active drug; use backup contraceptive for 7 days after discontinuing rifampin
- Anticonvulsants (eg. phenytoin, carbamazepine, barbiturates, topiramate, oxcarbazepine, lamotrigine): Reduces free serum concentrations of both estrogen and progestin
- HIV antiretrovirals (eg. Ritonavir, Darunavir): Reduces both effectiveness of COC and antiretroviral
Counseling for missed dose of COC
- If one dose is missed (<48hrs since a pill should have been taken), take the missed dose immediately and continue with the rest as usual
- If ≥2 consecutive doses are missed (>48hrs), take the missed dose immediately and discard the rest of the missed dose –> continue the rest as usual and have backup contraceptive for 7 days
- If pills were missed during the last week of hormonal tablets (eg. day 15-21), finish the remaining active pills in the current pack, skip the hormone-free interval and start a new pack the next day, backup contraceptive for 7 days
Advantages of Progestin-only pills (POP)
- Good for breast-feeding (avoid estrogen while breastfeeding), intolerant to estrogen, conditions that preclude estrogen
- Continuous pills (28 days pills)
Counselling points for initiating Progestin-only pills (Norethisterone)
- Start within 5 days of menstrual cycle/ bleeding –> no backup contraceptive required
- Start any other day –> require backup contraceptive for 2 days
Counselling for missed dose of Progestin-only pill
If late dose by >3 hours, back-up contraceptive for 2 days is required
What are the components in transdermal contraceptives
Both estrogen and progestin
Limitations of transdermal contraceptive
- Not as effective in patients >90 kg
- Continuous exposure to estrogen can increase risk of VTE
Limitation of transdermal rings
Continuous exposure to estrogen can increase risk of VTE
Frequency of progestin injections
IM injection every 12 weeks (3 months)
Limitation of progestin injection
- Return to fertility might be delayed
- Breakthrough bleeding especially in the first 9 months
- 50% of patients become amenorrhea after 12 months
- Regular doctor’s visit
Notable adverse effects of progestin injections
- Weight gain
- Short term bone loss –> reduced bone mineral density (Black Box Warning)
When to avoid progestin injections
- Older women
- Osteoporosis risk factors (especially long-term steroids) –> risk of bone loss
List the 2 long acting reversible contraception (LARC) available
- Intrauterine device (IUD)
- Subdermal progestin implants
MOA of IUD
- Inhibition of sperm migration
- Damage ovum
- Damage/ disrupt transport of fertilized ovum
- (if with progestin) Endometrial suppression and thickening of cervical mucus
Contraindication of IUD
- Pregnant
- Current STI
- Undiagnosed vaginal bleeding
- Malignancy of genital tract
- Uterine anomalies of uterine fibroids
Risk associated with IUD
- Uterine perforation
- Expulsion
- Pelvic inflammation
Uses for Levonorgestrel IUD
- To decrease menstrual flow
- Ideally used if concomitant menorrhagia
- Inserted for 5 years
- Side effects include: spotting and amenorrhea
Use for Copper IUD
- Used for heavier menses/ bleeding
- Ideally used if concomitant amenorrhea
- Inserted for 10 years
- Can be used as emergency contraception