Emeregency Contraception Flashcards
What is emergency contraception?
This is the intervention aimed in preventing unintended pregnancy after unprotected sexual intercourse or potential contraceptive failure.
When is emergency contraception used and why?
1.when the patient has a natural cycle and no contraception has been used:
-in this case we need to determine how at risk the patient is at potential pregnancy and what method would be most appropriate.
-if in doubt we always supply
- When there is incorrect use or potential failure in the hormonal contraception that is used:
-this contraception failure and it needs consideration of the type of contraception that is used and inform of the incorrect use of that method of contraception e.g. the missed pill rules - From 21 days after childbirth unless all LAM criteria is met
- From day 5 after miscarriage,abortion or ectopic pregnancy
What is the menstrual cycle length?
-the first day of menstruation (period ) is day one of the cycle
-the menstrual cycle is the time front he first day of menstruation up to the day before the next menstruation, the averaged cycle is around 28 days, but can vary from 21-40 days.
-THIS IS IMPORTANT TO HELP DETERMINE THE EXPECTED TIME FOR OVULATION.
How does oral emergency contraception work?
Works by delaying and slowing down ovulation.
If emergency contraception is taken after it is ineffective.
When does ovulation occur?
Occurs 14 days before menstruation (period) starts
How do we calculate the estimated ovulation time?
We woke of the patients predicated ovulation by determine the length of their cycle subtracting 14 off that .
-if the patient has an irregular cycle then calculate the likely ovulation date using the shortest cycle in the past 12 months.
What is the fertile period?
This is the most likely time for a likely to be at her most fertile state to get pregnant.
-this however, only occurs for a short amount of time
-it occurs near to ovulation
-a women is said to be most fertile the 5 days leading up to and including th estimated ovulation day ( 6 days)
When is the follicle stimulating hormone the highest?
This is around day 14 ovulation
How long are sperm viable after UPSI?
5 days
What happens if sperm is still present and ovulation occurs?
If ovulation occurs within the 5 days which sperm are present for then there is a potential risk of pregnancy
-once released an unfertilised egg can survive for 12-24 hours
What methods are available for emergency contraception?
Ulipristal (ellaOne)
Levonorgestrel (levonlle)
Copper IUD
What is the most effective method of emergency contraception?
COPPER IUD (more than 99% effective)
-it is effective during and after ovulation when oral emergency contraception will not work.
What is the mechanism of action of Copper IUD?
It has pre and post fertilisation mechanisms of action:
-it is spermicidal and toxic to the ovum and thus prevents fertilisation
-if fertilisation does occur, the copper IUD causes a local endometrial inflammatory reaction which prevents implantation
When can the copper IUD be inserted?
-up to 5 days (120 hours) after the first UPSI
Or
-up to 5 days after the earliest estimated day of ovulation (before the process of implantation has begun)
What are the contraindications of Copper IUD contraception?
-ovarian
-acute pelvic infection
-gynaecological cancers e.g. cervical
-undiagnosed vaginal bleeding
-pregnancy
-can’t be used until 4 weeks postpartum
How does levonorgestrel work?
The mechanism of action of levonorgestrel is that it delays the follicular development when administrated before the level of LH increases.
Up to how many hours can levonorgestrel be taken before?
72 hours after UPSI (3 days)
When does the levonorgestrel become ineffective and what would we give in replacement and why?
When the level of leutonising hormone begins to rise this is because this hormone tells the ovaries to release an egg making the female more likely to get pregnant.
We would give ullipristal
What are the indications of levonogestrel ?
Had UPSI with compromised contraception within the previous 72 hours
Or
Have had levonorgestrel but vomited within three hours of administration and are still within 72 hours of UPSI
How does ullipristal work?
It is a selective progesterone receptor modulator
-it inhibits follicular rupture even after the level of luteinizing hormone starts to increase.
-so essentially it inhibits the release of an egg despite the increase in LH.
How long does ullipristal have until it begins to be ineffective?
5 days (120 hours)
-this is the first choice if the UPSI occurred during the fertile period
-delays the follicular rupture for up to 5 days
What key information should the patient be aware of if after taking ullipristal?
-cannot start or redstart contraception until five days after taking ullipristal
-it may be less effective on those patients that have had the progesterone in the pre feeding 7 days
What is the only contraceptive that works after the ovulation stage and how does it do so ?
Copper IUD
-if an egg is already fertilised, the copper IUD can still stop pregnancy by preventing implantation.
Which contraceptive can you use for under 16s?
Ullipristal