Contraception Flashcards Preview

4th Year Drugs > Contraception > Flashcards

Flashcards in Contraception Deck (74):
1

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

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

2

How is the efficacy of contraception measured?

  • 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

What is contraception?

Prevention of pregnancy

4

When does pregnancy occur?

When implantation occurs

5

What are the risks of pregnancy?

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

6

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

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

7

What are the two broad types of contraception?

  • Hormonal
  • Non-hormonal

8

Name the non-hormonal methods of contraception

  • Intrauterine devices (IUD)
  • Sterilisation
  • Barrier methods
  • Natural methods
  • Withdrawal

9

What are the hormonal methods of contraction?

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

10

What are the UK MEC criteria for contraception?

  • 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

What do patients want to know about contraceptives?

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

12

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

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

13

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

  • Synthetic Oestrogen (ethinyl oestradiol) -
  • Progestogen

EXCEPT

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

14

How do COC work?

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

How often is the COC taken?

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

16

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

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

17

What do 'everyday' pills contain? What is their advantage?

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

18

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

 PFI (pill free interval) 

19

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

  • 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

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

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

21

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

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

22

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

  • levonorgestrel 

23

How do newer generations of progestogens compare to older protestogens?

  • 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

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

  • Progestogen type 

25

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

  • 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

What are the indications for COC use?

  • 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

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

  • >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

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

  • 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

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

  • 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

What are the main estrogenic side effects?

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

What are the progestogenic side effects of COC?

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

What are the minor side effects of COC?

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

What are the major complciations of taking the COC?

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

What are the benefits of COC?

  •  ↓ 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

Wwen should the COC be started? 

  • 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

When and how should the COCP be taken each day?

  • 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

What constitutes a 'missed pill'? What are the risks?

  • >48 hours after the last pill (ie more than 24 hours late) 

  • Risk of preg  - when and how many pills = missed

38

What are the Missed pill rules?

  • 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

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

  • 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

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

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

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

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

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

  • 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

What are the missed patch rules?

  • 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

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

  • 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

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

  • 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

What do progestogen only pills contain?

  • 'Mini pill' - contains low dose progestogen hormone
    • Older POPs: LEVONORGESTREL or NORETHISTERONE
    • Newer POPS: 'Cerazette' (DESOGESTREL)

47

How should the progestogen only pill be taken?

  • 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

WHat is the efficacy of the progestogen pill?

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

49

What are the indications for POP?

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

51

What are the SEs of the progestogen only pill?

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

52

WHat are the benefits of the progestogen only pill?

  • 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

What are the CIs for the progestogen only pill?

  • 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

What are the missed pill rules for POP?

  • 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

What medications interact with the POP?

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

56

Whats the follow up for women starting on the COCP?

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

57

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

  • Depo-provera, noristerat
  • Nexplanon

 

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

58

59

WHat are the characteristics of Dep-provera?

  • 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

What are the characteristics of noristerat and sayana press?

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

What are the characteristics of the nexplanon?

  • 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

63

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

  • Copper (IUD)
  • Progesterone bearing (IUS)

64

What are the characteristics of the copper IUD?

  • What is it?
  • Mech
  • Duration?
  • Efficacy
  • Indication
  • CIs

 

  • 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

What are the characteristics of the IUS?

  • What is it?
  • Mech
  • Duration?
  • Efficacy
  • Indication
  • CIs

  • 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

What are the SEs of IUDs/IUSs?

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

Can the IUS/IUD be used for emergency contraception?

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

68

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

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

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

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

70

What are the characteristics of levonorgestrel (levonelle)?

  • What?
  • Mech
  • Efficacy
  • Indications
  • SEs
  • Interactions
  • Specific advice
  • CI

  • 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

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

  • What?
  • Mech
  • Efficacy
  • Indications
  • SEs
  • Interactions
  • Specific advice
  • CI

  • 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

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

  • 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

What are the characteristics of female sterilisation?

How?

Mechs?

Indications

Effectiveness

SEs/Comps

 

  • 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

What are the characteristics of male sterilisation?

  • How
  • Mech
  • Efficacy
  • Comps
  • Reversal? 

  • 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