Contraception Flashcards
what is the Pearl Index?
number of contraceptive failures per 100 women years of exposure
contents of the COC
- Ethinyl oestradiol and progestogen
- Usual dose 20-35 micrograms EE (50 if on liver enzyme inducers)
- Second generation – levonorgestrel and norethisterone
- Third generation – gestodene and desogestrel
mechanism of COC
- Prevents ovulation
- Alters FSH and LH = no surge
- Prevents implantation by providing an inadequate endometrium
- Inhibits sperm penetration of the cervical mucus by altering quality and character of mucus
- Negative Feedback
how to take COC
21 days then pill free week
formulations of COC
pill
ring
patch
how to start COC
- Start days 1-5 without barrier contraception
- Takes 7 days to switch off ovaries
- Start anytime if not pregnant but use condoms for 7 days
non contraceptive benefits of COC
o Reduction in functional ovarian cysts – stops ovulation therefore no follicles form
o 50% reduction in ovarian and endometrial cancer
o Improvement in acne
o Reduction in benign breast disease, RA, colon cancer, osteoporosis
risks associated with COC
VTE ischaemia stroke focal migraines breast cancer cervical cancer
contents of the POP
• Cerelle/Cerazette – desogestrel pill with 12-hour window
mechanism of POP
• New POPs – Cerazette inhibits ovulation in 97% of cycles and although ha not been shown to be different from other POP in terms of its PI is likely to be more effective
• Mode of action
o Cervical mucus is rendered impenetrable by sperm
o A maximum effect about 48hrs after ingestion
o In older pills the effect is lost if more than 3 hours late
o Ovulation – spectrum of events
contents of depot medroxyprogesterone acetate
• Aqueous solution of crystals of the progestogen depomedroxyprogesterone acetate
how to take the depo contraceptive
150mg deep IM injection every 12 weeks
mechanism of depo injection
o High doses of progestogen
o Prevents ovulation
o Alters cervical mucus making it hostile to sperm
o Prevents implantation by rendering the endometrium unsuitable
consequences of depo injection
o No reduction in fertility but there is a delay of up to a year in return
o Reversible reduction in bone density
o Problematic bleeding
o Weight gain
subdermal implant contents
- Core – 68mg etonogestrel (ENG)
- Membrane – ethinyl vinyl acetate (EVA)
- Progesterone