COCs Flashcards
Female reproductive cycle
Ovarian cycle:
Period/menstruation - days 1-7
Follicular phase - 1-14.
Ovulation - day 14
Luteal phase - 15-28
Identify the hormonal changes that occur during the female reproductive cycle
FSH - Starts high, dips across follicular phase, peaks at ovulation, drops across luteal phase.
Estrogen - Start low, rises to peak just before ovulation, drops before rising again during luteal phase.
LH - spikes only during ovulation.
Progesterone - low until rising during luteal phase.
Anatomy relating to hormone changes
Ovaries secrete estrogen, estrogen acts on the hypothalamus, hypothalamus releases GnRH, GnRH acts on pituitary, pituitary releases LH and FSH which both act on ovary.
Ovary releases follicle which collapses into itself to form corpus luteum.
Estrogen and progesterone are found in follicle, corpus luteum, or uterus lining.
Advantages of COCs
Regular, lighter, less painful periods
Choose when periods occur
Improve acne and menstrual disorders
Reduce risk of PID, anaemia, and cancer
Advantages of nuvaring
No daily tablets
Regular periods and can pick when
Woman inserts and removes
Same as COCs
Disadvantages of COCs
Efficacy affected by drugs, vomiting, and diarrhoea
Taken each day at same time
Cause spotting, N/V, breast enlargment, tenderness, headache, fluid retention, BP increase, mood changes, VTE
Increased risk of MI and stroke in smokers >35
Disadvantages of nuvaring
Requires monthly insertion and removal
Vaginal irritation, infection, or discharge
Ring can be expelled
Explain COCs and use
Oral pill containing estrogen and progestogen
Inhibit ovulation
Reduce receptivity of endometrium to implantation
Thicken cervical mucous to form barrier to sperm
COC Indications (5)
Contraception
Acne
Menstrual disorders
Endometriosis
PMS
COCs contraindications (7)
Breast cancer - hormone-sensitive, worsen prognosis
Migraine w/ aura
Migraine > 35 y/o
History of VTE
Smoker > 35 y/o - increased VTE and CVD risk
End organ damage
COCs cautions (8)
Diabetes - increased risk of thrombosis
BMI>30 - increased risk of VTE
Smoker < 35 y/o
Hypertension - avoid use if BP not controlled
Surgery - increased thromboembolism risk (stop 4 weeks before, and then restart >2 weeks after)
Pregnancy - theory risk w/ cyproterone-containing
Breastfeeding - estrogen decrease milk supply
Postpartum - don’t use for 21 days or 42 days if VTE risk
COCs ADR risk considerations
Tolerance develops in the first 3 months of use
Benefits often outweigh risks
- Prevention of pregnancy
- Reduced menstrual loss
- Reduced ovarian cysts risk
- Reduced PID risk
- Reduced ovarian and endometrial cancer for 15 yrs
Common COC ADR
Breakthrough bleeding on low dose
N/V - because of estrogen
Breast enlargement and tenderness
Headache
Mood changes
Libido changes
Increased BP
Fluid retention
Melasma (hyperpigmentation)
Acne
Thrush
Infrequent COC ADR
Contact lense intolerance
Rash
Hirsutism (facial hair)
Alopecia
Altered lipid profiles
Hyperinsulinaemia (levonorgestrel COCs)
Insulin resistance
Rare COC ADR
Allergy (urticaria, angioedema)
Hypertension
Stroke
VTE
Photosensitivity
Jaundice, pancreatitis, liver cancer
Cervical cancer - increased risk w/ increased use
Breast cancer
VTE risk
Highest risk in first year of COC use, peak 3 mths
Depends on dose, type, and risk factors
Non-PBS pills = risk increases
Drug interactions with COCs
CYP3A4 induced antibiotics - within 4 wks of COC = contraceptive failure
e.g. griseofulvin, rifampicin, rifabutin
St John’s Wort - reduces hormones
Anti-epileptics - reduced hormone concentration
Increase COC dose to >50 mcg of ethinylestradiol
COCs regimen
Mostly 28 days w 21, 24, or 26 days.
Monophasic or multiphasic
Extended regimens shorten HFI
Monophasic regimen
Each active tablet contains same dose of estrogen and progestogen
Further classified by estrogen dose - low, standard, or high dose
Multiphasic regimen
Progestogen and/or estrogen content varies
More complex and associated w cycle symptoms (fluid retention, PMS)
No advantage over mono
Hard to change timing of withdrawal bleeds
Estrogen component
Ethinylestradiol - synthetic derivative
Low dose = 20 mcg
Standard = 30-35 mcg
High = 50 mcg
Mestranol - metabolised to ethinylestradiol
50 mcg = 35 mcg of ethinylestradiol (standard)
Estradiol - new, natural
No evidence that estrogen choice has clinical benefit
Progestogen component
2nd gen= levonorgestrel and norethisterone
Lower VTE risk, PBS subsidised
3rd gen= cyproterone, gestodene, desogestrel
Less androgenic but 2x VTE risk than levo
Not first-choice new users
Cyproterone has highest VTE risk
Used for severe acne, hirsutism
4th gen= drospirenone, dienogest, and nomegestrol
Drospirenone (yaz) - anti-mineralocorticoid activity (mild diuretic) and anti-androgenic
Dienogest and nomegestrol - anti-androgenic
New P is not PBS subsidised, but has less androgenic
PBS
Prog. only - norethisterone and levo
Low mono - Ethinyl+levo
Standard mono - Noresthist+ethinyl, levo
COCs counselling
Most have 21 days active and +/- 7 days HFI
- yaz and zoeley have 24 days active and 4 free
- qlaira has 26 active and 2 days inactive
- seasonique has no inactive
Active pills taken max 36 hrs between doses
HFI no longer than 7 days
7 day rule - takes 7 days to be/lose effective
Contraceptive risk if severe vomit/diarrhoea >24 hrs
Commencing COCs
Start on period, inactive tablet
7 days of actives = contraception protection
Quick start - long/unpredictable cycles, need immediate cover, risk of forgetting instructions - take pregnancy tests 4. wks later
7 day rule
7 actives needed to prevent ovulation
7 inactive fine, longer = ovulation risk
Risk greatest at the beginning or end of active pills
Week 3 missed = skip HFI
Qlaira and seasonique have product-specifics
Missed pill advice
Week 1 - riskiest to miss. Take EC if needed, take most recent missed pill, discard others, continue as normal, barrier methods for 7 days.
Week 2- safest. take most recent, discard others, barrier for 7 days, no EC needed.
Week 3- somewhat risky. Take most recent, discard others, barrier for 7 days, skip HFI and begin next active pack, no EC needed.
Monophasic regime indications
Standard dose- preferred, minimal ADR. For mild-mod hirsutism or severe acne. Stop after 3-4 cycles if resolved or no improvement.
Low dose- for teens or menopause, increases the risk of breakthrough bleed. 4 day HFI. For severe PMDD.
High dose- indicated for breakthrough bleeds on standard dose
Drospirenone
Mild diuretic progestogen
Estetrol (E4)
Plant-based, produced in human fetal liver. 4 day HFI.
Less effective for BMI >30.
Not recommended in BMI > 35.
Nomegestrol
Anti-androgenic activity. Zoely. Better tolerated in patients prone to mood disorders.
Triphasic
Indicated for heavy menstrual bleeding
Has some estrogen-only tablets
Similar cycle control to low-dose monophasic
Tricycling COCs
Running 3 cycle of actives together, 9 weeks straight
Decreased risk of menses, and dysmenorrhoea
Avoid PMS, withdrawal headaches
Prevent endometriosis
Avoid pill failure
Prevent herpes outbreaks with menstruation
Avoid heavy or painful bleeds
Breakthrough bleeding may occur at first
What if enzyme-inducing drugs are taken with COCs?
Use monophasic COC w/ levonorgestrel and ethinylestradiol AND increase dose to 50mcg ethinylestradiol
use either 2 30mcg tablets or 1 20mcg and 1 30mcg tablets.
use additional contraceptive methods, reduce HFI
Do not use microgynon 50 ED as progestogen dose is insufficient
Use of mestranol in COCs
Synthetic derivative of estradiol, metabolised to ethinylestradiol.
50mcg (standard dose) = 35mcg ethinylestradiol
use of 2nd gen progesterones in COCs
Levonorgestrel and norethisterone
- used for many years
- lower risk of VTE than other COCs
- only these are PBS
use of 3rd gen progesterones in COCs
Gestodene, desogestrel, cyproterone.
- gestodene and desogestrel are less androgenic than levonorgestrel, but twice the VTE risk
- not the first choice for new users
- cyproterone is anti-andorgenic
- used to treat androgenisation (severe acne, hirsutism)
- highest VTE risk of all COCs (cyproterone)
- not indicated in absence of androgenisation)
use of 4th gen progesterones in COCs
Drospirenone, dienogest, and nomegestrol
- dropirenone has anti-mineralocorticoid activity (mild diuretic and K retention) and anti-androgenic. no benefit.
- dienogest has anti-androgenic activity, VTE risk, advantage unclear.
- Nomogestrol has some anti-androgenic activity. no data on VTE risk, but risked in HRT.
benefit of newer progesterone components in COCs
Less androgenic (less like testosterone)
- beneficial on acne
- cause less hirsutism and weight gain
- not PBS listed though.
Extended pill regimen
Continuous tablet for fixed time period
shorten or remove HFI and avoid symptoms associated w/ HFI (headache, mood change)
delay, minimise or eliminate withdrawal bleeds
avoid heavy or painful withdrawal bleeds
Seasonique benefits
No inactive, no need to tricycle.
- Prevent endocrine and ovarian follicular development
- decrease PMS
- increase ovarian suppression
- period lasts 3 days
