Contraception Flashcards
What are the types of intrauterine devices?
- Intrauterine device copper bearing
- Intrauterine system progestogen releasing
What is the mode of action of the IUD?
Primary effect through copper ions- Direct toxic effect on sperm & ova, dec sperm motility, dec sperm survival
Secondary effect on endometrium: Impedes sperm transfer, sperm phagocytosis, impedes implantation
What are the disadvantages of an IUD?
Heavier periods but regular bleeding
Intermenstrual spotting initially
What is the mode of action of an IUS?
Thickening of cervical mucus inhibiting the passage of sperm
Prevention of endometrial proliferation
Local effect of foreign body on uterus
Prevention of ovulation in some women’s cycles
What are the disadvantages of an IUS?
Irregular bleeding & eventually amenorrhoea in some women
Much lighter in most women
Other than as contraception when else can an IUS be used?
Use in HRT & menorrhagia (Mirena 5years)
What substance is released by an IUS?
Levonorgestrel
In an emergency which intrauterine device is fitted?
Copper IUD
Must be done before implantation to ensure it is not causing abortion-5day rule. Works by inhibiting fertilisation
When must an emergency IUD be fitted?
Within 5days of risk OR ovulation
When can an emergency IUD not be fitted?
Not after day 19 in a 28day cycle.
Must avoid possible implanted pregnancy
How does the emergency pill Ulipristal work?
Selective progesterone receptor modulator. Delays/inhibits ovulation. Given immediately before ovulation it suppresses growth of lead follicles delaying follicular rupture until up to 5days later.
How long is Ulipristal licensed for?
Licensed for up to 120hours
As effective as Levonorgestrel <72hours
When is Ulipristal not recommended?
Enzyme inducers & progestogens may reduce efficacy
Not recommended in women w/ s.asthma
BF- discard milk for 7days
What are the brand names of Ulipristal?
EllaOne
Ulipristal Acetate
How does progestogen only emergency contraceptive work?
Levonorgestrel:
Delays ovulation- appears to prevent follicular rupture or cause luteal dysfunction.
What are the brand names of the progestogen only emergency contraceptive?
Levonelle 1500
Levonelle One Step
When should the progestogen only emergency contraceptive be taken?
Ideally within 72hours of intercourse
What are the issues with the progestogen only emergency contraceptive?
May displace Warfarin from binding sites & increase INR
Reduced efficacy of enzyme inducers
When is persona most reliable?
If sexual intercourse is restricted to after ovulation
Name a natural type of contraception
Lactational amenorrhoea method
How does male & female sterilisation work?
M:Vasectomy performed under LA through single incision.
Reversal possible but even if patent vas, development of anti-sperm antibodies may prevent fertility.
F: Laparoscopically using clips/rings/diathermy
Reversal may be attempted but success depends on the original method used
After male sterilisation what must happen before the method can be relied upon?
Wait approx 2months post procedure & have 2 negative specimens
Where are caps & diaphragms placed?
C: Cover the cervix
D: Covers the anterior wall of the vagina & cervix
Normally used with spermicide, made of latex/silicone
When is a diaphragm or cap unsuitable?
<6weeks postpartum
What is a condition required when using caps?
Spermicide reapplied for reused caps or in-situ caps for >3hours
How does the combined oral contraceptive pill work?
Monophasic 21pills with pill free interval
Synthetic oestrogen & progestogen prevent pituitary release of FSH &LH-prevent ovulation.
Cervical mucus changes to exclude sperm
Endometrial effects prevent implantation
What are the SE of the combined oral contraceptive pill?
Nausea, headache, irregular bleeding initially, mastalgia X3-5 VTE risk X2 ischaemic stroke risk Inc breast Ca X2 Cervix Ca at 10years
How long does the hormone given by the Evra combined Patch last for?
7 days
Changed weekly for 3weeks
4th week = withdrawal bleed
If same patch is used for >9 days assume cover is lost
How do progestogen only pills work?
Monophasic 28 pills No pill free interval Thickens cervical mucus Reduce endometrial receptivity May suppress ovulation
When should POP be taken?
Continuously
Within 3hours every day
How long do extra precautions need to be taken if a POP is missed?
48hours
Who is an injectable contraception (Depo Provera) ideal for?
Not affected by enzyme inducers so patients with HIV or epilepsy
What are the side effects of the Depo contraceptive injection?
amenorrhoea
Weight gain
Fertility delay (6-12months)
Reduced bone mineral density
How often is the Depo contraceptive injection given?
Every 12weeks
How long does the Nexplanon implant last for?
3years
What are the side effects of the Nexplanon implant?
80% irregular bleeding
20% amenorrhoeic
Fitting/removal under LA
What are the contraindications to fitting an IUD/IUS?
Pregnancy [4]
Undiagnosed bleeding [4]
Cervical/uterine cancer pre-treatment [4]
Active PID (or in last 3months) [4]
Current chlamydia, GC, Cervicitis [4]
Uterine abnormality (fibroids, bicornuate uterus) [3]
Gestational trophoblastic disease [4]
Long QT syndrome (increased risk of collapse during fitting) [3]
What is the number system for UKMEC classification for a method of contraception?
1= No restriction 2= Advantages outweigh risks 3= Risks outweigh advantages 4= Unacceptable health risk
What are the potential SE of an IUD/IUS?
- Expulsion: Most common in first 3 months after fitting & with heavy period (check threads)
- Perforation: Very rare, more common in early postnatal period in lactating women
- Pregnancy: 1/20 ectopic, can continue pregnancy if uterine but high risk of miscarriage, remove device if threads seen
- Infection: Risk of pelvic infection higher in 3 weeks post-insertion, screen for STIs before insertion
What are the indications for emergency contraception?
Diaphragm/cap is dislodged/removed within 6hours of sex
Diaphragm has been left in >3hours before sex & no additional spermicide applied
Condom splitting/breaking/slippage
Failure to use condom as advised when starting/switching contraception
If enzyme-inducing drugs being used alongside hormonal contraception and condoms are not being used
What are the possible SE of emergency contraception?
Nausea & vomiting (20%)
Breast tenderness
Dizziness, tiredness, headache
Disturbance of menstruation- common
What happens if someone vomits after taking emergency contraception?
If patient vomits within 2hours of Ulipristal or Levonorgestrel the dose should be repeated or IUD considered
What do most combined oral contraceptives contain?
Ethinyl Oestradiol
What are the different generations of progestogens?
1st: Norethisterone
2nd: Norgestrel, Levonorgestrel (Microgynon 30)
3rd: Gestodene, Desogestrel, Norgestimate
4th: Drospirenone, Dienogest
Newer Progestogens tend to have less androgenic side effects but are more expensive. Later generations have an increased risk of VTE.
What are the contraindications to taking the COCP? (Include the UKMEC numbers)
Smoking >age35 >15/day [4] <15/day [3] BMI >35 [4] BP >160/95 [4] >160/90 [3] Migraine with aura [4] Vascular disese (inc CVA) [4] History of VTE [4] Complex congenital heart disease [4] Breast Cancer [4] Liver disease (abnormal LFTs/tumour) [4]
What are the drug interactions associated with the COCP?
Enzyme inducers (Cytochrome p450)
Rifampicin
St John’s Wort
Some anti-retrovirals used in HIV (ritonavir)
Some anti-epileptics (Phenytoin, Carbamezepine, Phenobarbitone)
How is the absorption of the COCP reduced?
- Taking the pill accurately (missed pill) >24hours late, if in first week/>2 pills use additional contraception, mistake in last week run packs together
- Vomiting within 3hours of taking the pill
- GE
- Other drugs causing diarrhoea (Orlistat)
What are the contraindications to the Depo Provera injection including UKMEC numbers?
CVA [3] Diabetes with vascular complications [3] Severe cirrhosis, hepatoma [3] Multiple RF for CVD [3] Breast cancer [4]
For how long is Levonelle effective for?
72hours
Efficacy starts decreasing after first 24hours
For how long is EllaOne effective for?
120hours
Efficacy the same from first to last hour
What are the restrictions for giving Levonelle
Cannot give if another form of hormone treatment has been given 3days before
Cannot start a hormonal form of contraception for 5days afterwards
Including the UKMEC numbers what are the contraindications to the POP & Nexplanon?
- Breast cancer in last 5 years [4]
- Current enzyme inducers [3]
- Continuing use following a CVA [3]
- Severe cirrhosis, hepatoma [3]