Emergency Contraception Flashcards
When is emergency contraception used?
- used after episodes of UPSI
- this includes damaged condoms / missed pills
What is meant by “established pregnancy”?
How do EC methods interfere with this?
- established pregnancy is defined at implantation
- this occurs between day 6 and 12 post-fertilisation
- EC methods are NOT abortifacient as they work prior to implantation
What is the definition of post-coital contraception?
an intervention to stop pregnancy within 120 hours of fertilisation (5 days)
this is before implantation has occurred and pregnancy is “established”
What is the definition of post-coital contraception?
an intervention to stop pregnancy within 120 hours of fertilisation (5 days)
this is before implantation has occurred and pregnancy is “established”
How can the menstrual cycle be divided into 2 halves?
proliferative / follicular phase:
- this is the first half of the cycle that is oestrogen driven
- it can vary in length
luteal / secretory phase:
- this is the second half that is progesterone driven
- it is ALWAYS 14 days in length
How can the timing of ovulation be calculated?
How long does the ovum survive for?
- the timing of ovulation is cycle length minus 14 days
- the ovum survives for 12-24 hours
What is the survival of sperm like?
- the survival of sperm is 7 days
- traditional / conservative views stated 1-2 days
- it is more likely to be around 5 days
Why is a pregnancy test not always relevant when considering EC?
- a pregnancy test is not reliable until after 3 weeks
- patients may be advised to re-perform one in 3 weeks despite EC
What are the 3 most important areas to cover in an EC history?
LMP / cycle length:
- to calculate date of ovulation
(if someone has irregular cycles, minus 14 from the shortest cycle they have had)
timing of UPSI:
- the most recent and all UPSI in this cycle
potential contraceptive failure:
- e.g. missed pills / condom accident
- potential medication interactions
- antituberculosis
- antiretroviral
- antiepileptic
- St John’s Wort
What are the 4 indications for EC?
- UPSI on any day of a natural menstrual cycle
- UPSI from day 21 post childbirth
- UPSI from day 5 after abortion, miscarriage or ectopic pregnancy
- regular contraception has been compromised / used incorrectly
At what points in the cycle is someone most fertile?
- most fertile at / around the time of ovulation
- the pregnancy risk is negligible on day 1-3
- and the risk is very low 48 hours after ovulation due to demise of the ovary
What are the 3 options for emergency contraception?
levonorgestrel 1500mcg:
- must be taken within 72 hours of UPSI
- e.g. Levonelle / Upostelle
ulipristal acetate 30mg:
- must be taken within 120 hours of UPSI
- e.g. EllaOne
copper coil:
- can be inserted within 5 days of UPSI
When must levonorgestrel be taken to be effective?
within 72 hours of UPSI
When must ulipristal acetate be taken to be effective?
within 120 hours of UPSI
- this is more powerful / effective than levonorgestrel
What is the most effective method of EC?
copper IUD
- this is not affected by BMI, enzyme-inducing drugs or malabsorption
- it also provides ongoing contraception
At what points during the menstrual cycle is EC offered?
- it is offered at ANY time during the cycle
- it is unlikely to be effective if ovulation has already occurred
- the woman should be advised to take a pregnancy test in 3 weeks / if her period is delayed
What is levonorgestrel and how does it work?
- it is a progestogen
- it works by preventing / delaying ovulation by suppressing the LH surge for up to 5 days
(it is not effective if the LH surge has already occurred, but fertility is reduced after demise of the ovum anyway)
- it is not harmful in pregnancy if this does occur
When can contraception be started following levonorgestrel?
- COCP or POP can be started immediately
- condoms should be used for 7 days after starting COCP
- condoms should be used for 2 days after starting POP
What is the dose of levonorgestrel that is given?
- 1.5mg as a single dose
- 3mg as a single dose if BMI > 26** or **> 70kg
(double dose is also given with enzyme-inducing drugs but this is off licence)
What is done if vomiting occurs after levonorgestrel?
- the dose must be repeated if vomiting occurs within 3 hours
- nausea & vomiting are common side effects
What are the other side effects associated with levonorgestrel?
- spotting / changes to next menstrual period
- diarrhoea
- breast tenderness
- dizziness
- depressed mood
How does levonorgestrel affect breast feeding?
- it is NOT harmful in breastfeeding, so this can continue
- it is advised to avoid breast feeding for 8 hours after taking the dose
How does ulipristal work?
- it is a selective progesterone receptor modulator (SPRM)
- it suppresses the LH surge, but more powerfully than levonorgestrel
- it prevents / delays ovulation
What advice is given around starting contraception after ulipristal?
!! WAIT 5 DAYS !!
- when starting COCP, use condoms for initial 7 days
- when starting POP, use condoms for initial 2 days
What dose of ulipristal is given?
- a single dose of 30mg
- unlike levonorgestrel, this dose CANNOT be doubled
What are the limitations to the use of ulipristal?
- as the dose cannot be doubled, it cannot be used with enzyme-inducers
- it is not known whether UPA or LNG is more effective when BMI > 30** or **weight > 85kg
- breast-feeding must be avoided for 1 week after use
What are the contraindications to ulipristal?
severe asthma
What should happen if vomiting occurs after taking ulipristal?
if vomiting occurs within 3 hours, the dose must be repeated
What are the other side effects associated with ulipristal?
- breast tenderness
- N&V
- back pain
- mood changes
- spotting / changes to next menstrual period
- headache / dizziness
- abdominal / pelvic pain
What are the significant drug interactions associated with ulipristal?
UPA is less effective if:
- progestogens have been taken in the 7 days prior
- progestogens are taken in the 5 days following
- enzyme inducers
When is UPA used?
if patient presents 72-120 hours post-UPSI and does not want an IUD
When is the IUD used as emergency contraception?
- it can be fitted up to 5 days after UPSI
OR
- within 5 days of earliest calculated day of ovulation
- this is 14 days before the cycle ends
- e.g. day 12 for a 26 day cycle
- it is recommended when there have been multiple episodes of UPSI within the last few days
Why is the copper IUD the first line for EC?
- it is 99% effective
- it can be used for ongoing contraception
- it is toxic to the ovum + sperm and inhibits implantation
How long should the copper IUD be kept in for if it is not wanted for contraception?
- it needs to be kept in until at least the next period
- after this, it can be removed
What is the major side effect associated with the copper IUD?
- insertion can lead to pelvic inflammatory disease
- this is more likely in women who are high risk for STIs
What are the disadvantages to copper-IUD fitting?
- periods can become longer, heavier + painful
- there is a risk of perforation
- there is a risk of expulsion
- there is an increased risk of ectopic pregnancy
When is insertion of a Cu-IUD strongly encouraged?
- around the time of ovulation, the chance of pregnancy from a single act of UPSI is 30%
- after ovulation has occurred, levonorgestrel + ulipristal are less likely to be effective
- the IUD will still work to be toxic to the sperm / ovum
Why can the Cu-IUD only be inserted up to 5 days after UPSI?
- the earliest date of implantation is 6 days after ovulation
- the IUD must be inserted prior to implantation occurring
