Contraception Flashcards
What is perfect use failure rate of the pill?
0.3%
What is perfect use and typical failure rate of condoms?
2% and 15%
What are the UK MEC classifications?
- No restriction
- Advantages outweigh risks
- Risk outweighs advantages (requires expert judgement or referral to specialist)
- Unacceptable health risk
What to include when counselling on contraception?
- Method Use
- “Missed rules”
- Reasons for method failure, drug interactions
- Side effects
- Serious symptoms to report
What are the three combined methods?
Pill
Patch
Ring
What is mode of action of combined methods?
Main - Oestrogen and progestogen prevent pituitary release of FSH and LH – no ovulation
Added - Endometrial effects prevent implantation and cervical mucous changes exclude sperm
How to take combined pill?
Take pill for 21 days, then 7-day break (or ED, 28 days)
How to use combined patch?
Patch stuck onto skin (1 per week for 3 weeks, 1 week off) Alternate site each week.
How to use combined ring?
Flexible ring worn for 21 days then discarded, new ring inserted 1 week later. Flexible and easy to insert/remove.
Common side effects of combined contraception?
Nausea, mastalgia, headache, initial irregular bleeding
Benefits of combined methods?
Decrease in PID, ovarian cysts, ovarian and uterine cancer.
Control of bleeding
Reduction in benign breast disease
Risks of combined methods?
Increased risk of VTE, Stroke and MI (in smokers) Ca breast (small) Ca cervix (x2 at 10 years)
Contraindications of combined methods?
Smoking >35 yrs >15 day BP >160/95 or >160/90 Migraine with aura Vascular disease (inc. CVA) History of VTE Congenital heart disease Breast Cancer Liver disease
Interactions of combined methods?
P450 inducers
Phenytoin, phenoarbitone and carbamazepine
Rifampicin
Some antiretrovirals (HIV)
St John’s Wort
Ways combined pill may be ineffective?
Not taking pills accurately
Vomiting within 3 hours of taking
Diarrhoea
What counts as a missed dose for the COCP? What should you do?
Missed = >24 hours late
Two or more pills missed –> use condoms or abstain for 7 days
If missed in first week –> EC
Mistakes in last week –> run packs together
What is a missed dose of the combined patch?
Sufficient hormone for 9 days
Assume lost cover is same patch on for >9 days.
Assume cover lost if patch has fallen off and not been replaced in 24 hours
What is a missed dose of the combined ring?
If ring is out for more than 3 hours or more than once a cycle, contraceptive efficacy is lost
Extended ring free week = lost efficacy
Starting combined method? (normal circumstances)
- Anytime if no pregnancy -condoms for 7days
* Day 1-5 – effective immediately - unless very short cycle (<23 days condoms 7 days)
Starting combined method? (post-partum)
Day 21 no condoms
Day 22 – 28 use condom for 7 days.
After day 28, must exclude pregnancy
Starting combined method? (post-TOP or miscarriage)
<24 weeks- straight away, no condoms or any time if no further risk of pregnancy.
> 24 weeks- day 21, no condoms or after day 21, condoms for 7days
General mode of action of progesterone only methods?
- Prevent ovulation, thicken cervical mucus and reduce endometrial receptivity
- Importance of each varies with each method
- Uses synthetic progestogens (hormone is progesterone)
Difference in MoA between traditional POP and desogestrel?
Deso prevents ovulation, POP may prevent ovulation
Main method of action of implant?
Prevent ovulation
Main method of action of mirena coil?
Thicken cervical mucus
Reduce endometrial receptivity
Local effect of foreign body on uterus
Main method of action of depo?
Prevent ovulation
How to take POP?
Taken continuously, 1 pill a day each day
How implant is administered
Single subdermal implant
What is mirena coil?
IUS - levongestrel
How is depot administered?
IM injection to buttock/thigh/arm
Side effects of progesterone only methods?
Bleeding irregularities (unpredictable)
Progestogen side effects = headaches, mood changes, weight gain, acne
Side effects of POP?
Irregular bleeding
Side effects of implant?
Irregular (80%)
No bleed (20%)
Can use COCP
Side effects of mirena coil?
Irregular bleeding and eventual amenorrhoea in some cases, overall much lighter periods.
Side effects of Depo?
No bleed (70% by 1 year) 3kg weight gain by 2 years (only one proven to cause this) Delay in return of fertility (6-12 months)
Contraindications to POP?
Breast cancer in last 5 years
CVA, cirrhosis, hepatoma, current p450 inducer use
Contraindications to implant?
Breast cancer in last 5 years
CVA, cirrhosis, hepatoma, current p450 inducer use
Contraindications to mirena coil?
Pregnancy, undiagnosed bleeding, PID in last 3 months, current clam, GC or cervicitis, cervical/ uterine cancer pre-treatment. Uterine abnormality, long QT syndrome, Gestational trophoblastic disease
Contraindications to depo?
Multiple risk factors for CVD, CVA, Diabetes with vascular complications, Cirrhosis, hepatoma, breast cancer.
Interactions of POP?
Enzyme inducers
Interactions of implant?
Enzyme inducers
Who is depo good for?
HIV or epilepsy patients - not affected by enzyme inducers
Missed dose rules for progesterone pill?
Traditional POP = 3 hours
Desogestrel (cerazette) – 12 hours
If missed, additional precautions for 48 hours and consider EC
How long does implant last?
3 years
How long does mirena coil last?
5 years
How long until progesterone pill is effective?
Day 1-5 effective immediately
After day 5 abstain/ condoms for 2 days
How long until implant is effective?
Day 1-5 effective immediately
After day 5 abstain/condoms for 7 days
How long until mirena coil is effective?
Day 1-7 effective immediately
After day 7 abstain/condoms for 7 days
How long until depo is effective?
Day 1-5 effective immediately.
After day 5 abstain/condoms for 7 days.
Failure rate of copper IUD?
<2% over 5 years
How long does copper IUD last?
5-10 years`
if fitted over age of 40 can stay until no longer required - advised to stop IUD after 1 year of amenorrhoea if >50, 2 years if <50
When is copper IUD fitted?
Fitted normally in first half of menstrual cycle, or at any time if certain the patient cannot be pregnant
When is copper IUD effective
Immediately
Mode of action of copper coil?
Primary (through cooper ions)
Direct toxic effect on sperm and ova
Decreased sperm motility
Decreased sperm survival
Secondary (effect on endometrium)
Impedes sperm transfer
Sperm phagocytosis
Impedes plantation
Contraindications of copper IUD?
Same as mirena coil
Side effects of copper IUD?
o Heavier periods but regular bleeding – much lighter in IUS.
o Intermenstrual spotting initially
NB:- beware of change in bleeding pattern in established user – cancer can be missed if assume due to IUD.
Aide memoire for counselling on IUS/IUD?
E and 6 Ps
- Expulsion
- Pregnancy (failure rate and ectopic)
- Perforation
- Periods
- PID
- Procedure
- Progestogenic Side effects (for IUS)
Risk of expulsion of IUS/IUD? How to check for it?
1 in 20 - Most common in the first 3 months after fitting with heavy menstruation
Should check threads after every period, to check they can feel their threads but not the device protruding from the cervix
Risk of perforation with IUS/IUD?
1 in 1000
More common in early post-natal period when breastfeeding
Risk of ectopic pregnancy in IUD?
1 in 20 IUD conceptions will be ectopic (1% risk in the general population anyway so IUD still has less ectopics overall – absolute risk of pregnancy very small anyway)
Pregnancy in IUD?
If pregnancy is viable and uterine then may continue, remove device if threads can be seen to reduce the risk of miscarriage
If pregnancy is uterine, can continue but higher miscarriage rates – remove device if threads can be seen.
Risk of infection with IUD?
IUD does not cause pelvic infection
Risk higher only in the 3 weeks following insertion
Screen for chlamydia/STIs before insertion if history suggests risk.
May treat empirically if emergency insertion and the patient is high risk. (Azithromycin and metronidazole)
3 methods of emergency contraception?
IUD
Ullipristal (ellaOne)
Levonogestrel (Levonelle)
What is the principle upon which emergency IUD works?
Implantation happens 6-12 days post-fertilisation so IUD must be done before implantation (within 5 days of risk or ovulation)
How does emergency IUD work?
• Copper is toxic to the ovum and sperm so the copper IUD is effective immediately after insertion and works by inhibiting fertilisation.
When can emergency IUD not be used?
• Not after day 19 in 28-day cycle (or shortest cycle minus 9 days) unless only one risk within 5 days (i.e. must avoid possible implanted pregnancy)
What must you do if you need to refer the patient on for emergency IUD?
Give oral EC too
What is ullipristal acetate (ellaOne)?
Selective progesterone receptor modulator
Until when can you give ullipristal?
Up to 120 hours post-risk
What is mode of action of ullipristal?
Inhibition/delay of ovulation
Before LH surge - suppresses growth of lead follicles
After LH surge - prevent ovulation and delays follicular rupture up to 5 days later
At time of LH peak or after - ineffective at delaying follicular rupture
Contraindications of ullipristal?
Allergy/pregnancy
Not recommended in severe and uncontrolled asthma
Breastfeeding - should express and discard for 7 days
What may reduce efficacy of ullipristal?
Enzyme inducers
Other progestogens - leave 5 days after use to start hormonal contraception
What is Levonelle?
1 tablet containing 1500mcg of levonorgestrel
When do you need to take levonelle by?
72 hours of intercourse - pregnancy risk increases with delay of treatment
Mode of action of levonelle?
Delays ovulation - if taken prior to LH surge itresults in ovulatory dysfunction in subsequent 5 days
What may interfere with levonelle?
Enzyme inducing drugs - dose doubled
Side effects of emergency contraception?
Very few in practice
N+V - repeat dose if within 2 hours of levo and 3 hours of ullipristal
How is female sterilisation done? Failure rate? Reversal?
Laparoscopically
1 in 200 lifetime risk
Can be attempted but not guaranteed
How is male sterilisation done? How long before can rely upon it? Lifetime failure rate? Reversal?
Under LA - single incision
2 months and 2 negative samples
1 in 2000 lifetime
Reversal possible but development of anti-sperm antibodies may stop fertility returning