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Flashcards in Birth Control Deck (16)
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1

Where does fertilization happen?

Fallopian tubes

2

Ingredients for viable pregnancy?

ovulation
viable sperm
intercourse
cervix that admits sperm
patent fallopian tubes
meeting of eggs and sperm
healthy endometrium

3

What are some non-chemical methods?

~ using cycle length to predict fertile days
~ ovulation predictor kits (LH surge immediately precedes ovulation)
~ basal body temperature - spikes right AFTER ovulation as progesterone rises
~ cervical mucous - thickens post ovulation under progesterone -> reduces sperm motility, prior to ovulation under estrogen thin and stretchy

4

"permanent" methods of birth control?

~ (fallopian) tubal ligation, often laparoscopic, often after last C-section
~ vasectomy (takes ~3 months post procedure, sperm testing necessary, interruption at vas deferens

5

examples of barrier methods?

~ condoms
~ vaginal sponge
~ cervical cap
~ diaphragm
~ spermicides

6

MOA of combined estrogen/progesterone pill?

estradiol:
~ inhibits release of FSH at ant. pituitary - no follicular recruitment - no ovulation

progesterone:
~ inhibits LH release at ant. pituitary - prevents ovulation
~ endometrium not as receptive to ovum (more blood vessels, more friable)
~ mucous thicker and harder to navigate through for sperm
~ reduces tubal peristalsis (sperm and egg have trouble meeting)

7

what are some names for progesterone?

norgestrel (think NOrGESTation)
levonorgestrel
norethindrone acetate

what is a common name for estrogen?
ethinyl estradiol (like alcohol, but with more "i"s)

8

modes of combined hormonal contraceptives?

pills - monophasic/triphasic
Alesse - good low dose start - but b/c low dose can result in breakthrough bleeds
Tri-cyclen - triphasic with changing progesterone levels
Yasmin/Yaz - improved acne


transdermal patch - Ortho-Evra (think feet = skin, so transdermal), 3 weeks on, each week, 1 week off
vaginal ring - Nuvaring - 3 weeks in 1 week off

9

progesterone only contraception, MOA?

~ reduces LH release - prevents ovulation
~ unreceptive endometrium - in the cycle, interrupted progesterone - endometrium develops blood vessels and grows more; continuous exposure of the pill - prevents endometrial growth and thin endometrium results => light and short menses, in some nonexistent -> great for menorrhagia (excessive bleeding during period) and dysmenorrhea (excessive pain during menstruation) treatment
~ thicker mucous for sperm to travel
~ decreased tubal peristalsis

10

What are some benefits of oral contraceptives apart from contraception?

~ menorrhagia improvement
~ decreased anemia
~ dysmenorrhea improvement
~ decreased perimenopausal symptoms
~ treatment of PMS
~ treatment of acne
~ decreased PID
~ decreased ectopics
~ decreased epithelial ovarian and endometrial CA

11

Examples of progesterone-only contraception?

~"micro-pill" = MICROnor - norethindrone 0.35 mg
taken daily, no pill free interval
most women have regular cycles
great for postpartum breastfeeding
suitable for women with thromboembolic or CV disease or those with intolerances to estrogen
but: can have mood changes, acne, hirsutism, weight gain, headache, breast tenderness, irregular menstrual bleeding


~IM/SubQ injection of Depo-Provera (think IM so DEEP) - 1 injection every 3 months (q12-14 wks), usually no period, must be done within 5 days of menses but decreased bone density
but restoration of fertility can take up to 1-2 yrs

~ IUD - "Mirena", "Jadess" - levonorgestrel


12

How do IUDs work?

~ inflammatory changes in endometrium and fallopian tubes - > toxic to sperm and ova -> prevents fertilization and implantation

~ Mirena, Jadess (levonorgestrel) -> also changes in cerfical mucous and endometrial atrophy/thinning
lasts 3-5 years; really well liked b/c of light periods

~ copper - no hormones, just irritation "Nova T", Flexi T", lasts 3-10 years

~ S/E: Copper: increased blood loss and duration of menses, dysmenorrhea
progesterone: bloating and headache

~ absolute counter indications:
known or suspected pregnancy
undiagnosed genital bleed
PID
STIs
for copper: Cu allergy or Wilson's

13

Emergency contraception examples?

non-hormonal: copper T IUD - can be done in up to 7 days post-activity, 1% failure, can only use copper (no Mirenas)

hormonal: Plan B = levonorgestrel 1.5 mg x 1 dose or 0.75 mg q12 h x 2 doses

Yuzpe method = EE 100 microgram and levonorgestrel 0.5 mg q12X 2 doses

both pills best within 72 hrs of unprotected intercourse

effectiveness: without emergency contraception 8% pregnancy, with emergency contraception 1% end in pregnancy

Plan B considered better than Yuzpe, less S/E and greater efficacy

neither way is abortive

14

common side effects of oral contraceptives?

ESTROGEN:
- headache
- nausea
- weight gain (rare)
- fluid retention
- thromboembolic events
- liver adenoma
- breakthrough bleeding if estradiol levels low in the pill
- migranes and headaches

PROGESTERONE:
- amenorrhea
- headaches
- increased appetite
- decreased libido
- modd chagnes
- hypertension
- acne/hirsutism

15

common contraindications of oral contraceptives?

- known/suspected pregnancy
- cardiovascular disease
- coagulopathy or prior thromboembolic events
- smoker > 35
- estrogen-dependent tumours (breasts, uterus)
- impaired liver function - can make worse
- congenital hypertriglyceridemia ~ can increase thromboembolic events
- uncontrolled hypertension - progesterone can make worse
- migraines with focal neuro symptoms - can make worse

16

Before prescribing contraceptives:

~ history and physical to evaluate risks, including blood pressure and breast exam (need to rule out estrogen-dependent tumours)
~ schedule follow-up visit 6 weeks post intake
~ pelvic exam (can be delayed till next visit)