Short acting reversible contraception Flashcards
What options are available for short acting contraception
Combined hormonal contraception
Progesterone only pill
emergency contraception
What forms of CHC are there
COC, CTP (combined transdermal patch), CVR (combined vaginal ring)
How do CHC work
interrupt the hypothalamic-pituitary-ovarian axis
also have effects on mucous and endometrium
What is the regime for COC
pill taken for 21 days then omitted for 7 to induce withdrawal bleed
first seven pills inhibit ovulation and the following 14 maintain anovulation
after how many COC pill free days will follicular activity resume
9 days after pills stopped
what does COC pill contain
ethinyl-estradiol and levonogesterel
what is the regime for the patch
Patch worn for 7 days and then new patch applied every 7 days for two weeks. No patch worn for seven days to induce withdrawal bleed
first patch inhibits ovulation and other two maintain anovulation
What is regime for ring
ring worn in vagina for 21 days and then removed for seven to induce withdrawal bleed
Describe some tailored-regimes
tri-cycling: 3 packs taken back to back and then 7 days off
shortened hormone free interval: pill taken for three weeks and then 4 days off
extended use: pill taken continuously until breakthrough bleed occurs and then pill not taken for 4-7 days
what metabolic effect does EE have
reduces levels of antithrombin III and protein S
causes systemic hypertension
thus increasing risk of atherosclerosis / DVT / MI etc
What factors must be taken into account when using COC
obesity smoking BMI (less effective if low BMI) diabetes immobility hypertension / previous vascular problems anti-phospholipid syndrome
what side effects can COC have
migraine (without aura)
weight gain
mood swings
unscheduled bleeding
what effect does CHC have on cancers
increases risk of: cervical and breast cancer
decreases risk of: endometrial and ovarian cancer
what side effects does the ring have
acne and mood swings
what side effects does patch have
breast pain, nausea, irregular bleeding, painful periods
When can CHC be started?
within first five days of cycle
any time in cycle if certain not pregnant and condoms / abstinence used for 7 days
What happens if one pill is missed
missed pill can be taken up to 48 hours after it is missed
if more than 48 hours after missed pill, take most recent missed pill, continue others as normal and use condoms for 7 days
What are the rules concerning patient adherence to patch regime
patch can be off for 48 hours
can be left on for 9 days (7 days + 48 hours)
patch can be omitted for up to 9 days
what does progesterone only pill contain
levonogesterel
norethisterone
etonorgesterel
How does POP work
primarily by thickening cervical mucous
also inhibits ovulation in most cycles
also decreases endometrium receptivity to blastocyst
How is POP taken
continuously with no break
What effect does POP have on metabolism
very little effect
