Contraception Flashcards
When you may need to give a patient contraception- what must you take into consideration holistically?
how long sperm survive in female tract, how long ova survive + how long do they take to reach uterus & implant
- Social – coercion, current relationship
- Psychological – mood, consequences of pregnancy
- Physical – STI prevention and contraception, but also opportunity to address adverse heath issues
Remember!:
Sperm can survive 5 days, Ova can survive 24 hours
Ova are fertilised in fallopian tube & take 4 days to reach uterus + implant
What are the advantages of male and female condoms?
What are the disadvantages of male and female condoms?
What are diaphragms? Give the adv and disadvantages of it
What other “fertility awareness” methods are there to prevent pregnancy?
- Basal Body Temp: 0.2-0.5 rise after ovulation. If SI restricted to post ovulation - 6.6% pregnancy rate
- Cervix position/shape – not recommended
- ‘Cervical mucus consistency: SI after 3 days of opaque mucus
- Combined methods
- Urinary LH detection: Failure rate is 6.5%
- Lactational amenorrhoea: if amenorrhoeic, breast feeding women w <6m old baby – 98% of women unlikely to become pregnant
What is the mechanism of hormonal contraception?
4 actions of progesterone? - cervical mucus, ovulation, effect on endometrium, cilia motility?
Just oestrogen would infinietly proliferate the endometrium– this is why progesterone is given too!
Oestrogen: prevents ovulation
Progesterone:
- makes cervical mucus hostile to sperm
- prevents ovulation
- can cause atrophy of endometrium so its hostile to implantation
- reduces cilia motility in Fallopian tubes
What are the combined oral contraceptives?
What is the latest pg type derived from?
.
What are contraceptive + 3 non contraceptive benefits of combined pill?
Reliable, Safe, Unrelated to coitus, Woman in control, Rapidly reversible
Halves ovarian + endometrial cancer risk if taken for ~5 yrs: as there is no ovulation - ovarian capsule isn’t breached monthly - so no need to be constantly repaired! + also makes endometrium inactive, so not constantly turning over
Helps endometriosis, PMS, dysmenorrhoea, menorrhagia, PCOS.
Cont. use stops periods, which reduces many issues!
What are the serious (rare) risks of the contraceptive pill?
V small number of women may develop VTE
Risk is greatest in: Very overweight, immobile, severe varicose vein pts, close family history of VTE before 45.
Risk of arterial thrombosis is greatest in women who:
Smoke, have diabetes, high bp, very overweight, close family history of MI or stroke under 45.
Compare the positive vs negative effects of combined hormonal contraceptives
Who should be advised against the use of CHCs?
What are contraindications for the pill? vs 4 relative contraindications?
Breast cancer; undiagnosed genital bleeding; pregnancy; <3 weeks post partum; hypertension; PH thrombosis; migraine with aura; active liver disease; thrombophilia; SLE; thrombotic thrombocytopenic purpura; smoking more than 15 >35
Relative contraindications
BMI>35; migraine without aura; diabetes; hyperprolactinoma
Now can be used when breast feeding established 6/52 post partum
Which drug interactions affect the COC, POP and implant?
Liver Enzyme inducing drugs, eg: Antiepileptics: carbamazepine, primidone, topiramate
Antibiotics: rifabutin, rifampicin may reduce E2 circulation
Antiretrovirals- always use HIV Drug Interaction Checker to identify potential interactions!
Antidepressants St John’s wort
Others modafinil, bosentan, aprepitant
What are the rules for the pill?
Compare 3 Progestogen Only Methods?
non user dependent
User dependent methods:
Progesterone implants (last 3 years, reversible) - IUS Mirena coil (5 years)
Progesterone only pills (POPs)
Desogesterel (Cerazette, Cerelle, Desorex). This is taken same time daily, no breaks, lasts 12hrs
- Other pills below only have a 3hr window!
Injections: IM- Depo Provera (12 weekly) & Noristerat (8 weekly)
What is the efficacy of Prog only contraception?
what does insertion & removal require?, risk of systemic side effects?, reversible?. reason for discontinuation?
How do IUDs work?
main action, 3 ways they prevent implantation?
- Cu IUD inserted into uterus, may be left in situ long term
- Cu ions destroy sperm
- Main action is delaying fertilization
- Secondary action is preventing implantation - done thru Inflammatory reaction, prostaglandin secretion + as well as a mechanical effect.
Benefits vs risk of IUDs?
4 IUD contraindications?
- Current pelvic inflammatory disease
- Suspected or known pregnancy
- Unexplained vaginal bleeding
- Abnormalities of uterine cavity
Describe the Intrauterine System/Mirena
what can it be used to treat, what can it offer, what is its action - despite this what can happen, what is a Kyleena?
Good contraceptive
- Treatment of HMB
- Offers pg when using oestrogen patches for HRT in menopause to prevent endometrial hyperplasia
- Pg mainly local action very little systemic absorption - however can be some irregular bleeding in first 3-6 months
- Kyleena= small device for younger women/smaller cavities
compare 2 methods which can be used as emergency contraception
when can they be used, failiure rate, what they do in 1st vs 2nd part of cycle,
Postcoital pills:
- 72-120 hrs after UPSI
- Failure 1-1.7% and increases w time
- Postpones ovulation in 1st part of the cycle- so beware!
- May prevent implantation in 2nd part of the cycle?
- Can be used twice in same cycle but not switched between 2 types
Copper IUDs:
- Up to 120 hrs after presumed ovulation or 120 hours after UPSI at any time of the cycle
- Failure extremely rare
- Copper kills sperm + prevents implantation in 2nd part of the cycle. This is the method of choice
differences between Levonelle & ellaOne?
components, dosage & efficacy, effectiveness, contraindications, when can they be taken?
Also- both of them contraindicated in pregnancy
Side effects such as nausea, vomiting, headaches
