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4th Year Drugs > Contraception > Flashcards

Flashcards in Contraception Deck (74)
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1
Q

If it existed, what would be the characteristics of a perfect contraceptive?

A
  • 100% effective
  • Safe and reversible
  • Independent of intercourse
  • Cheap/free
  • Non-invasive
  • Acceptable to all religions/cultures
  • Prevent STIs
2
Q

How is the efficacy of contraception measured?

A
  • Pearl Index - risk of pregnancy per 100 woman years of using contraceptive method
  • Eg if PI = 2, of 100 woman using it for a year, two will get pregnant by the end
  • Users compliance - user dependent contraceptives eg pills/condoms - perfect use > typical use
3
Q

What is contraception?

A

Prevention of pregnancy

4
Q

When does pregnancy occur?

A

When implantation occurs

5
Q

What are the risks of pregnancy?

A
  • Sperm survival ( can survive up to 7 days)
  • Only 30% of females are fertile in fertile window
6
Q

What are the long acting forms of contraceptives? How long does each last?

A
  • Injectables (3 months)
  • Implants (3yrs)
  • Intrauterine system (IUS)/devices (IUD) (5 yrs)
7
Q

What are the two broad types of contraception?

A
  • Hormonal
  • Non-hormonal
8
Q

Name the non-hormonal methods of contraception

A
  • Intrauterine devices (IUD)
  • Sterilisation
  • Barrier methods
  • Natural methods
  • Withdrawal
9
Q

What are the hormonal methods of contraction?

A
  • Implants
  • Intrauterine system (IUS - Mirena)
  • Injectables
  • Pills
  • Patches
  • Vaginal Rings
  • Emergency contraception
10
Q

What are the UK MEC criteria for contraception?

A
  • 1: No restriction (A = always)
  • 2: Advantages outweigh risks (B = Benefits outweigh risk)
  • 3: Risks outweigh advantages (requires expert judgement or referral to specialist) (C = use with caution)
  • 4: Unacceptable health risk (D = Don’t even think about it!)
11
Q

What do patients want to know about contraceptives?

A
  • Side effects - bleeding, weight, pain
  • Risks? - future fertility How effective it it How does it work?
12
Q

What do health care professions want to know about patients who want contraceptives?

A
  • Whats the patient choice
  • Dangerous patients
  • Compliance - Method/user failure, understanding
13
Q

What do all combined contraceptive pills contain? What are the exceptions?

A
  • Synthetic Oestrogen (ethinyl oestradiol) -
  • Progestogen

EXCEPT

  • Qlaira and Zoely contain oestrodiol valerate (metabolised in body to naturally occurring oestrodiol)
  • Mestranol in Norinyl-1
14
Q

How do COC work?

A

ANOVULANT

  • Osterogen has negative feedback on FSH (follicles do not develop)
  • Progestogen has negative feedback on LH (no ovulation)
    • Also causes endometrial atrophy and thickens cervical mucus
15
Q

How often is the COC taken?

A

One active pill is taken daily for 21 days out of every 28 (3 weeks on, 1 week off)

16
Q

What happens once the patient has finished the pill packet by the end of week 3?

A
  • Withdrawal bleed - reduced progestogen stimulus on endometrium
  • The cycle is then restarted
17
Q

What do ‘everyday’ pills contain? What is their advantage?

A
  • Taken everyday without a break - but have 7 inactive pills
  • Aids compliance
18
Q

If not everyday preperations, what is week where there are no pills taken referred to as?

A

PFI (pill free interval)

19
Q

What preperations do most COC come in as? What does this mean? How do others come as?

A
  • Monophasic pills - delivers same dose of oestrogen and progesterone everyday.
    • 21 pills (3 weeks on, one week off)
  • Diphasic and monophasic - vary the dose throughout the pack, in two or three phases
20
Q

What is the dose that most COCs come as? (ethinyloestradiol)

A
  • Ethinyloestradiol - 20µg (low dose), 30µg or 35µg (standard dose)
    • e.g. microgynon 30
21
Q

How many generations of progestogens are there? WHat progestogens belong in each generation?

A
  1. 1st generation - Norethisterone
  2. 2nd generation - norgestrel, levonorgestrel
  3. 3rd Generation - Gestodene, Desogestrel, Norgestimate
  4. 4th Generation - Drospirenone, Dienogest
22
Q

What type of progestogen is used in the most common COC brand (Microgynon 30 )?

A
  • levonorgestrel
23
Q

How do newer generations of progestogens compare to older protestogens?

A
  • Have less androgenic side effects
  • Newer the progestogen, the more expensive the pill tends to be
  • Slight increase in risk of VTE - not clinically important!
24
Q

Which characteristic of the COC pill determine bleeding patterns the most? Progestogen type, oestrogen dose or type of phasic regime?

A
  • Progestogen type
25
Q

What is the efficacy of COC preperations (PI)? How is COC efficacy affected?

A
  • Perfect: PI = 0.1 per 100 woman years
  • Typical Use = 5%
  • žFailure rate of 1% = 30,000 unplanned pregnancies
  • Low dose (20 mcg) and standard dose (30, 35 mcg) = similar efficacy
    • However small margin for error
    • I.e. doses only sufficient to prevent ovulation in some women
26
Q

What are the indications for COC use?

A
  • Contraception - ‘from menarche (+ condoms) to menopause’ (40 yrs old without CV RFs)
  • Menstrual cycle control
  • Menorrhagia
  • Premenstrual syndrome
  • Dysmenorrhoea
  • Acne/hirsutism
  • Prevention of recurrent cyts
27
Q

What patients are given COC becauser the beenfits outweight the risk?

A
  • >40+
  • Smoking - <35yrs
  • Obesity - BMI >30
  • Hx of ↑BP in pregnancy
  • Major surgery without immbolisation
  • Superficial thrombophlebitis
  • Uncomplicated valvular disease
  • Non-focal migraine and <35 yrs
  • Asymptomatic gallbladder disease
  • Uncomplicated DM
  • Hyperlipidaemia
  • VTE in 1st degree (<45yrs, check thrombophilia screen)
  • Undiagnosed Breast, CIN or Cervical Cancer
  • Sickle cell disease
28
Q

What patients should the COC pill be cautioned in (Category 3: risks outweigh benefits)?

A
  • Age >40yrs
  • Postpartum <21 days
  • Smokers: <15 cigs and >35 yrs
  • Hypertension: ( 140/90 - 159/99)
  • Non-focal migraine and >35yrs
  • Hx of breast cancer
  • Gallbladder disease (symptomatic or on medical Tx)
  • Cirrhosis (mild compensated)
  • Taking enzyme inducers
  • Breastfeeding (<6 months post-partum) - suppresses lactation
29
Q

What patients are COC completely CI in? (category 4 - absolulte contraindication)

A
  • Current or Hx of VTE
  • Smokers: >15 cigs and >35 yrs (↑ VTE risk)
  • Breastfeeding <6 weeks postpartum
  • BMI > 40
  • Focal migraine (with aura)
  • Hx of CVA, IHD, Valvular heart disease
  • žMultiple risk factors for Arterial CV
  • Severe hypertension (>160/100)
  • Pregnancy (↑ VTE risk)
  • Major surgery with immoblisation (stop at least 4 weeks before)
  • Active breast/endometrial Cancer - oestrogen dep
  • Inherited thrombophilia
  • DM with vascular complications
  • Active/chronic liver disease
30
Q

What are the main estrogenic side effects?

A

Estrogenic - usually not a problem with modern low dose pills

  • Nausea
  • Headaches
  • ↑ vaginal discharge (mucus; non-infective)
  • Fluid retention (bloating) and weight gain (↑ appetite)
  • Breast enlargement/tenderness
  • Chloasma - tan or dark skin discoloration
  • Photosensitivity
31
Q

What are the progestogenic side effects of COC?

A

Progestogenic SEs - If problematic, select 3rd Generation pill (much less likely with newer pills)

  • Acne
  • Greasy hair
  • Hirstuism
  • Depression/Pre-menstrual tension-like Sx
  • ↓ labido
  • Weight gain (↑ appetite)
  • Vag dryness
32
Q

What are the minor side effects of COC?

A

Oestrogenic and progestogenic SEs may occur. Most common:

  • Nausea
  • Headache
  • Breast tenderness
  • Breakthrough bleeding - common in first few months. Usually settles >3 months
    • If not, consider chaning pill (diff progestogen/ ↑ ethinyloestradiol dose)
33
Q

What are the major complciations of taking the COC?

A

Very rare. Usually, risks of pregnancy outweight risks of COC. Minimised by careful selection/follow up.

  • VTE (older 30mcg COCs: 15 per 100,000). Risk ↑ with:
    • Smoking (60 per 100,000; CI: >15 cigs day & >35 yrs)
    • ↑ age and obesity (CI: BMI >40)
    • Pregnancy (60 per 100,000)
    • 3rd generation pills containing gestodene or desgestrel (30 per 100,000)
  • ↑ CVA risk (but ONLY with CV RFs)
    • 1st degree FHx (<45yrs), DM, HTN, smoking, age >35yrs, obesity
  • Focal migraine
  • ↑BP
  • Jaundice
  • ↑ Risk of Liver, cervical and breast carcinoma
34
Q

What are the benefits of COC?

A
  • ↓ menstrual disorders
    • Functional ovarian cysts x 92%
    • Menorrhagia, irregular bleeding x 50%
    • Dysmenorrhoea x 40%
    • PMS
  • ↓ Iron def anaemia
  • PID
  • ↓ ectopic preg (x90)
  • Fibroids
  • ↓ Hirtuism/acne
  • ↓ Endometrial, ovarian and bowel cancer
35
Q

Wwen should the COC be started?

A
  • On 1st day of menstrual bleeding (but can be between 1-5 days without condoms, UNLESS very short cycle e.g. <23 days)
  • If started any other time, use condoms for 7 days
  • žPost partum to day 21 - no condoms
  • Immediately after emergency contraception - but use condoms for 7 days
36
Q

When and how should the COCP be taken each day?

A
  • Take at approximately the same time of day (easier to remember - habitual!), for 21 consecutive days
  • Followed by 7 days pill-free days (or 7 days of neutral tablets in 28 pack) to allow endometrial shedding and withdrawal bleed (↓ progesterone)
    • Contraception still provided during 7 day interval
37
Q

What constitutes a ‘missed pill’? What are the risks?

A
  • >48 hours after the last pill (ie more than 24 hours late)
  • Risk of preg - when and how many pills = missed
38
Q

What are the Missed pill rules?

A
  • If 1 missed - no extra contraception and continue as normal
  • Always: if 2 or more missed- extra contraception for next 7 days. take current day and missed day pill (even if 2 in one day). leave earlier missed pills.
  • Pills missed at beginning/end of the pack confer the most risk of pregnancy.
    • If week 1 - consider emergency contraception if unprotected sex in pill free interval/week 1
    • If week 2 (Days 8-14): after seven consecutive days of taking the COC there is no need for emergency contraception*
    • If week 3 (Days 15-21): finish pills in her current pack and start a new pack the next day; thus omitting the pill free interval
39
Q

What advice should be given if the women has diarrhoea and vomiting?

A
  • žIf vomit/diarrhoea within 2hrs of taking pill, take another ASAP
  • Vomiting or severe diarrhoea for more than 24 hours - keep taking pill but follow same advice as if they had missed pills (i.e missed pill rules)
40
Q

What are the drugs interactions that impact the efficacy of the COCP?

A

žCOCP = metabolised by PY450!

  • Antibiotics - Rifampicin, Rifabutin
  • žAntidepressants - St. John’s Wort
  • žAntiepileptics - Carbemazepine, Oxcarbazepine, Phenytoin, Primidone, Topiramate, Phenobarbitol
  • žAntifungals - Griseofulvin, Imidazoles & Triazoles
  • žAnti-retrovirals - (HIV Rx)
  • žOther - Bosentan, Modafinil, Tracolimus

Only mirena coil and depot injection can be used with enzyme inducers – all others cannot be used at same time

41
Q

What are the rules if patient is using enxyme PY450 inducers short term and long term drugs and COCP?

A

žLong term Inducers - if, having considered other methods, still choose COCP should be offered a regime containing 50mcg EE or mestranol (?+ condoms).

ž- Short term Inducers - condoms + COCP for 4wks afterwards.

42
Q

What are the characteristics of the combined transdermal (EVRA) patch?

A
  • EVRA patch - transdermal adhesive patch
    • Releases ethinyloestradiol (34ug) plus progestogen norelgestronim (immediately effective)
    • Apply to clean, hairless, non-irritated place on body and where clothing = loose
      • Abdomen, upper outer arm, upper torso (back or front, not tits), bum (apply to different place each week!)
    • New patch weekly for 3 consecutive weeks, and one patch free week (can get withdrawal bleed)
    • Similar SEs, efficacy and CIs to COCP
43
Q

What are the missed patch rules?

A
  • Sufficient hormone for 9 days - if same patch on >9 days, cover = lost
  • If patch fallen off and not replaced within 24hrs - cover lost
  • Replace patch which has fallen off with new one
44
Q

WHat are the characteristics of the combined vagonal ring? (Nuvaring)

A
  • Latex-free ring - releases 15ug ethinyloestradiol and 120ug progestogen (etonogestrel) to inhibit ovulation
  • Insert into vag (by patient) and worn for 3 weeks. Then remove to allow for 7-day ring free week (withdrawal bleed). Insert new ring
  • SEs: less oestrogenic SEs that COCP
  • Advice: recommended not to but may be removed for MAX 3 hrs during sex.
  • Efficacy: same efficacy as COCP if used properly.
45
Q

What is the mechanism by which the progesterone-only pill works?

A
  • Thickened cervical mucus- Hostile and prevents sperm reaching egg
  • Thin endometrium - preventing implantation
  • Inhibition of ovulation (older pop 50%; Cerazette i.e. desogestrel containing = 95%)
46
Q

What do progestogen only pills contain?

A
  • ‘Mini pill’ - contains low dose progestogen hormone
    • Older POPs: LEVONORGESTREL or NORETHISTERONE
    • Newer POPS: ‘Cerazette’ (DESOGESTREL)
47
Q

How should the progestogen only pill be taken?

A
  • EVERY DAY (inc during periods), at same time - within 3 hours. If desogestrel, within 12 hours. Packs of 28.
  • Immediately effective:
    • If started on day 1-5 of period - no extra contraception needed
    • If started > 5days - use condom for first two days (until POP = effective)
  • If just had baby - effective <21 days postpartum. If begin >Day 21 postpartum, use additional contraception for two days.
48
Q

WHat is the efficacy of the progestogen pill?

A

Pearl Index - 0.3-0.8% (worse than COCP); 99% effective

49
Q

What are the indications for POP?

A

Useful where COCP = contraindicated e.g.

  1. During lactation - has no effect on quality/quantitity of milk
  2. Sickle cell disease
  3. SLE/autoimmune
  4. Thrombophilias
50
Q
A
51
Q

What are the SEs of the progestogen only pill?

A
  • Bleeding irregularities - unable to predict! e.g. reg, irregular, amenorrhoea
  • General progestogen SEs:
    • Headaches
    • Mood changes
    • Weight gain
    • Mastalgia
    • acne
52
Q

WHat are the benefits of the progestogen only pill?

A
  • No increased risk of VTE. can therefore be used by some women who cannot take the COCP
    • e.g. > 35 and smoke,migraines, HTN, breastfeeding
53
Q

What are the CIs for the progestogen only pill?

A
  • Breast cancer in last 5 years [4]
  • Current enzyme inducers [3]
  • Continuing use following a CVA [3]
  • Severe cirrhosis, hepatoma [3]

[3] = requires expert judgement or specialist referral

[4] = unacceptable health risk

54
Q

What are the missed pill rules for POP?

A
  • If >3hrs late (12hrs for cerazette/desogestrel containing..) - take missed pill asap and use next pill at usual time. Use condoms for 48hrs
  • If vom within 2 hrs of taking - take pill asap and as usual thereafter. Use condom for 48hrs
55
Q

What medications interact with the POP?

A

Enzyme inducers (same as COCP) - increase metabolism and thereby reduce efficacy

56
Q

Whats the follow up for women starting on the COCP?

A

Ideally three months (if not before) - repeat BP and enquire about SEs/problems

57
Q

What are the long acting reversible contraceptives (LARCs) that are avaliable? How do they work?

A
  • Depo-provera, noristerat
  • Nexplanon

Progestogens are slowly released - bypass portal circulation. Mode of action similar to POP + causes anovulation

58
Q
A
59
Q

WHat are the characteristics of Dep-provera?

A
  • Contains medroxyprogesterone acetate. Injection every 3 months
  • Failure rate: PI <1.0
  • Causes irregular bleeding in first weeks, then amenorrhoea.
  • Indications: breastfeeding, ↓ compliance
  • CIs: multiple CV RFs, CVA, DM + vascular compromise, severe cirrhosis/hepatoma - [3], breast cancer [4] (CVs due to ↓ HDL with hogh progestogen levels)
  • SEs: ↓ bone density (cessation restores it), prolonged amenorrhea (18 months for fertility to return) , weight gain
    • Therefore, not preferable in teenages and women with osteoperosis risk
  • Interactions: NOT AFFECTED BY ENZYME INDUCERS
60
Q

What are the characteristics of noristerat and sayana press?

A

Noristerat

  • Contains norethisterone enantate - given IM every 8 weeks. Similar efficacy to depo-preovera.
  • NOT for long term use. Short term interim contraception e.g. waiting for vasectomy

Sayana press

  • SC preperation of medroxyprogesterone acetate (licenced for self administration) - provides 13 weeks cover.
61
Q

What are the characteristics of the nexplanon?

A
  • Rod containing progestogen, ETONOGESTREL - inserted into upper arm betweem bicep and tricepindent subdermally with LA
  • PI < 0.1 (as safe as sterilisation), 99% effective.
  • Lasts 3 years but can be removed whenever
  • SEs: progestogenic Sx, esp irregular bleeds in 1st yr (no drop in bone density)
  • CIs: same as POP (breast cancer, enzmye inducers, CVA, cirrhosis/hepatoma)
  • Interactions: enzyme inducers
62
Q
A
63
Q

What are the two types of intrauterine devices? (‘the coil’)

A
  • Copper (IUD)
  • Progesterone bearing (IUS)
64
Q

What are the characteristics of the copper IUD?

  • What is it?
  • Mech
  • Duration?
  • Efficacy
  • Indication
  • CIs
A
  • What?: T-shaped rod - 5% UK
  • Mech: Copper content - foreign body reaction (toxic reaction) that stops impantation and inhibits sperm motility
  • Duration: 5 - 10 years (can be taken out sooner)
  • Efficacy: PI 0.6-0.8, 99% effective. Effective straight away!
  • Indications: Hormonal contraception = CI (part older women), can be put in anytime (provided not pregnant), straight after pregnancy/TOP
  • CI: pregnant, 48hrs- 4 weeks post delivery, unexplained vag bleeds, vag/pelvic infection, abnormal womb, pelvic cancer
65
Q

What are the characteristics of the IUS?

  • What is it?
  • Mech
  • Duration?
  • Efficacy
  • Indication
  • CIs
A
  • What? T shaped rod that slowly releases progesterone (Levonorgestrel (LNG) - LNG-IUS
  • Mech: thins lining of uterus preventing implantation, thickens cervical mucus preventing sperm reaching egg, sometimes stops ovulation. Fertility returns as soon as removed, regular periods may take time.
  • Duration - 3 (jaydess and levosert) - 5 (mirena) years
  • Efficacy: PI 0.1 (99% effective). Effective immediately if <7 days of period starting. If >7days, condoms (for 7 days)
  • Indications: contraception, menorrhagia, dysmenorrhoea, endometriosis.
  • CIs: STIs/Untx infection, breast cancer, endometrial or cervical cancer, v large fibroids , HIV (medication interactions)
66
Q

What are the SEs of IUDs/IUSs?

A

1 E and 6Ps

  • Expulsion
  • Periods (heavier, more painful in IUD; ↓ with IUS (irregular/amenorrhoea))
  • Pregnancy (failure rate and ↑ ectopic: 1 in 20 only IF pregnant ∴ v v low!),
  • Perforation
  • PID (ascending - not suitable for STI prone) - check for infection 1st!
  • Procedure - crampy pains (up to 48hrs post) - take NSAIDS/paracetamol before and after procedure.
  • Progestogenic side effects if IUS (Nausea, headache, breast tender, bloating, ovarian cyst, irregular lightbleeding/amenorrhoea, acne, reduced labido) - less that POP as only locally acting
67
Q

Can the IUS/IUD be used for emergency contraception?

A
  • IUS - NO
  • IUD - yes, if within 5 days of ovulation (takes 5 days for egg to implant!) (failure rate <1%)
68
Q

What are the three types of emergency contraception? Whats the order of effectiveness?

A

In order of effectiveness….

  1. Copper Intrauterine device
  2. Selective progesterone receptor modulator (SPRM) - ulipristal acetate (UPA)
  3. Oral progestogen -only emergency contraceptive (POEC) - levonorgestrel (LNG)
69
Q

What does the UK law say with regards to the definition of pregnancy and emergency contraception?

A
  • Pregnancy beings at implantation 6-12 days (usually given as 9 days), not fertilisation
  • Therefore, emergency contraception is NOT abortion
70
Q

What are the characteristics of levonorgestrel (levonelle)?

  • What?
  • Mech
  • Efficacy
  • Indications
  • SEs
  • Interactions
  • Specific advice
  • CI
A
  • What? Single oral dose of 1.5mg levonorgestrel (LNG)
  • Mech: delays/inhibits ovulation by working on HPA axis. Therefore, NOT effective after ovulation has taken place.
  • Effectiveness: <24hrs = 95%; <72hrs - 85%, > 72hrs - 58% (use copper IUD)
  • SEs: DNV, Menstrual irregularities (delay/spotting), dizziness, Breast tenderness.
  • Interactions: enzyme inducers
  • Specific advice: If vom <2hrs of taking, repeat dose needed. Use condoms for 7days if on COCP or 3 days for POP
71
Q

What are the characteristics of selective progesterone receptorm modulators (SPRM) - uliprstal acetate (ellaOne)

  • What?
  • Mech
  • Efficacy
  • Indications
  • SEs
  • Interactions
  • Specific advice
  • CI
A
  • What? Contains ulipristal acetate (UPA) - 1x 30mg tablet
  • Mech? Inhibits or delays ovulation. Also blocks action of progesterone. After the LH peak = not effective.
  • Indications: Given <5 days of unprotected sex.
  • Efficacy: ~99% if taken <5 days
  • SEs: N&V, dizziness, menstrual irregularities (delayed/sooner), muscle and back pain, pelvic and abdo pain, headache, mood swings
  • Interactions: enzyme inducers, compete with progestogens in contraceptive pills for progestron receptors (↓ efficacy of contraceptives)
    • Use condoms for 14 days if on any contraception EXCEPT POP (9 days)
  • Specific advice: if vom <3hrs of taking, take another ASAP
  • CI: pregnancy/suspected pregnancy, breastfeeding (avoid for 1 week after), severe liver disease, uncontrolled asthma
72
Q

What are the characteristics of the copper IUD in emergency contraception? When should it be followed up?

A
  • Mech: inhibits fertilsiation by direct toxicity (affects implantation by inducing inflammatory reaction in endometrium) and reduces sperm motility
  • When? <5 days (<1% failure rate)
  • Follow up - 3-4 weeks to test for pregnany and discuss future contraception/remove IUD if wanted.
73
Q

What are the characteristics of female sterilisation?

How?

Mechs?

Indications

Effectiveness

SEs/Comps

A
  • How: Filshie clip applied to F tube laproscopically, occluding the lumen (under GA). Hysterectomy also.
  • Mech: interuption of fallopian tube so sperm cannot reach egg
  • Indications: both Dr and PT = staisfied there will be no regret (permanent). Older women whose family = complete/disease CI pregnancy.
  • Efficacy: PI: 0.5% (1 in 200 failure rate) (worse than male!)
  • Comps: permanent sterilisation (regret), ↑ risk of ectopic (if failure), infection, anaesthetic comps, bleeding, viseral damage (laproscopy), post op pain
74
Q

What are the characteristics of male sterilisation?

  • How
  • Mech
  • Efficacy
  • Comps
  • Reversal?
A
  • How/mech: Vasectomy - ligation and removal of small segment of vas deferens (preventing sperm release). Done under LA.
  • Efficacy: More effective than female (1 in 2000 failure rate after 2 negative semen analyses)
  • Comps (5%): Failure, post op haematoma, infection, chronic pain
  • Reversal: successful in 50% - preented by anti-sperm antibody formation