Contraception Flashcards
1
Q
2 classes of hormonal contraception
A
Combined hormonal contraception
Progestogen only contraception
2
Q
How do CHCs work?
A
oestrogen and progesterone act on the hypothalmo-pituitary ovarian axis to suppress LH and FSH prodution
this inhibits ovulation (no surge in LH and FSH)
3
Q
What does a surge in LH and FSH cause?
A
Ovulation
4
Q
What changes do CHCs do to the cervical mucus?
A
Increase cervical mucus which acts as a mechanical barrier to sperm
5
Q
What do CHCs do to the endometrium?
A
Cause thinning of the endometrium which reduces the chances of implantation
6
Q
How does the endometrium become thin?
A
Oestrogen causes the endometrium to proliferate and grow which is opposed by progestogen which prevents hyperplasia (excessive growth) of the endometrium
The endometrium becomes thin, fragile and prone to bleeding
7
Q
What does the 7 day pill free interval do?
A
Causes oestrogen and progestogen concentrations to fall
Causes the endometrium to shed, mimicking menstruation
Known as a withdrawal bleed
8
Q
What do combined oral contraceptives contain?
A
Oestrogen and progesterone
9
Q
What is in the oestrogen component?
A
Synthetic oestrogen - ethinlyestradiol
Some contain mestranol
10
Q
What does the progestogen component contain?
A
levonorgestrel
norethisterone
desogestrel
gestodene
drospirenone
11
Q
First generation of progestogen?
A
norethisterone
12
Q
2nd generation of progestogen
A
levonorgestrel (LNG)
13
Q
3rd generation of progestogen
A
desogestrel
gestodene
norgestimate
14
Q
How do COC preparations differ?
A
In how the doses vary over the menstrual cycle
15
Q
2 types of COC preparations
A
Monophasic COCs
Phasic COCs
16
Q
Monophasic COCs
A
First line
Amount of oestrogen/progestogen in each tablet is constant throughout the cycle
Most commonly prescribed
17
Q
Phasic COCs and 3 types
A
Amount of oestrogen/progestogen varies over the 21 days
Biphasic: contain 2 different sets of active tablet
Triphasic: contain 3 different sets of active tablet
Quadraphasic: contain 4 different sets of active tablet
18
Q
Example of biphasic and triphasic COCs
A
Biphasic- Binovum
Triphasic - Trinordiol
19
Q
When are phasic COCs used?
A
In women who don’t have withdrawal bleeding or who have breakthrough bleeding with monophasic preparations
20
Q
Example of a low strength COC
A
20mcg ethinylestradiol
21
Q
Adv/disadv of low strength ethinylestradiol
A
- useful if risk factors for circulatory disease
- can cause disrupted bleeding patterns
22
Q
Standard strength COC
A
- 30-35 mcg ethinylestradiol in monophasic COCs
* 30–40 mcg ethinylestradiol in phased preparations
23
Q
Equivalent dose of Mestranol to 35mcg ethinylestradiol
A
50 mcg
24
Q
2 COC preparations (standard and ED)
A
- standard preparation - calendar strip of 21 active tabs, 1 taken daily for 21 days and then no tablet taken for 7 days (HFI)
- ED preparations - useful when compliance is a concern, taken continuously, no HFI, 21 active tablets and 7 inert/placebo tabs taken days 22-28 to allow withdrawal bleed
25
What is Qlaira?
* Quadriphasic pill used in treatment of heavy menstrual bleeding
* Start on day 1 of the cycle
* 28 tabs taken continuously
* Missed pill rules differ
26
What is Dianette?
* Co-cyprindiol- Cyproterone acetate and ethinylestradiol 2000/35
* not indicated for just a contraceptive
* Used in women who require oral contraception and suffer from acne or hirsutism (hair growth)
* Carries an Increased risk of venous thromboembolism (VTE)
27
Initiation of monophasic COC days 1-5
* day 1-5: no additional contraception is needed.
| * Ideally start on day 1 of the cycle
28
Initiation of monophasic COC day 6+
Day 6 of menstrual cycle onwards:
Additional precautions are required for 7 days after starting
(9 days for Qlaira)
29
Initiation of monophasic COC postpartum
Postpartum:
up to and including day 21 postpartum – no additional contraception required
(if not breast feeding and no VTE risk)
30
Initiation of monophasic COC and miscarriage/termination
If started immediately after or up to day 5, no additional contraception required
31
What is the standard regimen for COCs?
21 days (21 active pills) and 7 days pill free period
or
28 days (21 active pills and 7 inactive pills) and no pill free period
32
Tailored use - shortened hormone free interval
21 days (21 active pills) and 4 pill free days
33
Tailored use - extended use (tri cycling)
Taken for 9 weeks (3 x 21 active pills)
| 4 or 7 days of pill free interval
34
Tailored use - flexible or extended use
Continuous use (> 21 days) of active pill until breakthrough bleeding occurs for 3-4 days
4 days of hormone free period
35
Tailored use - continuous use
Continuous use of active pills
| No hormone free interval
36
Is there a benefit for hormone free interval?
No
37
Benefits of not taking the hormone free interval
* avoids monthly bleeds
* reduced withdrawal symptoms such as headache and mood changes
* reduced the risk of escape ovulation and pregnancy
38
What can happen when no pill free period is taken?
Unscheduled bleeding is common
39
Are tailored regimes licenced?
No
40
Risk of failure if COC used perfectly
Low <1%
41
Risk of failure if COC used typically
9% failure
42
Questions for missed pill
* when the contraception was missed (time since last pill taken)?
* how many pills were missed?
* where are they in the cycle?
* which pill is the patient taking?
43
What to do if one pill has been missed or < 48hrs since last pill? (COC)
* take the late/missed pill
* continue taking the remaining pills at usual times (even if more than one in a day)
* no additional contraception needed
44
If 2+ pills missed and > 48hrs since last pill (COC)
* take the most recent pill asap (other missed pills discarded)
* continue taking the remaining pills at usual time (even is more than 1 in day)
* use additional contraception (condoms) or avoid sexual intercourse until pills have been taken for 7 consecutive days
45
What to do if pills were missed in the last week of pills (days 15-21)?
Omit the hormone free period and finish the pills in the current pack and start a new pack the next day
46
What to do if it has been 9+ days since last pill taken?
* consider EC if UPSI
* missed pill taken asap
* abstain/barrier method until 7 consecutive pills have been taken
47
Advantages of COCs
* more effective than barrier methods
* menstrual bleeding is usually regular, lighter and less painful
* reduced severity of acne in some women
* reduced incidence of pre-menstrual tension (PMT)
* reduces risk of ovarian, endometrial and colorectal cancer
* normal fertility returns immediately after stopping the COC
48
Disadvantages of COCs
* temporarily ADR - headache, nausea, breast tenderness, mood changes (don’t stop in few months, change type of COC)
* BP may increase
* no protection against STDs (use condom)
* less effective than long active reversible methods of contraception
49
COC interaction with enzyme inducing antibiotics
Enzyme inducers reduce the effectiveness of COCs which can lead to contraception failure
50
Examples of enzyme inducing antibiotics
Rifampicin
Rifabutin
51
Short term treatment (< 2 mths) with enzyme inducing antibiotics and COCs
• change to an alternative method of contraception
OR
• continue and use barrier while taking and for 28 days after
52
What does breakthrough bleeding mean during short term enzyme inducing antibiotics and COC?
A complication that indicates low serum level oestrogen concentrations
53
What to do when taking COC and long term (> 2 mths) enzyme inducing antibiotic?
Change to an alternative method of contraception
54
What are non-enzyme inducing antibiotics?
Most broad spectrum antibiotics
55
Precautions for non-enzyme inducing antibiotics and COCs
* no precautions required
| * additional precautions if vomiting or diarrhoea occur
56
Examples of other enzyme inducing drugs
Anti-epileptics:
- Carbamazepines
- Phenobarbital
- Phenytoin
- Topiramate
57
COCs and lamotrigine
COC can increase clearance of lamotrigine leading to poor seizure control
58
Is lamotrigine an enzyme inducer?
No
59
Other enzyme inducing drugs COCs can interact with
Antiepileptics
Herbal - St. John’s Wort (OTC)
60
Short term treatment of enzyme inducing drugs and COCs (antiepileptics, lamotrigine, herbal)
Change contraception method or use COC with extended regimen and use barrier/abstain
Abstain/barrier while using and for 28 days after
61
Long term treatment of other enzyme inducing drugs and COCs
Additional contraception method required
62
What to do if vomiting within 3hrs of taking COC?
Take another one asap
63
If vomiting/severe diarrhoea > 24hrs COC
Follow instructions for missed pill
Each day of vomiting/diarrhoea is a missed day
Abstain/barrier during and 7 days after
If illness occurs while taking last 7 days omit any HFI and start next cycle
64
Risk of MI/stroke with COCs
Vey small increased risk
Increase in those with multiple risk factors for these conditions - smokers, hypertension, migraines with aura, Fx Hx of CVD
65
Hypertension limits to avoid COCs because of risk of MI/stroke?
> 160/100 mmHg
66
Risk of VTE on COC
Low risk
Risk depends on progestogen type and oestrogen dose
Assess VTE risk
DVT/PE signs stop immediately
67
Breast cancer and cervical cancer risk with COCs
Very small increased risk
returns to no risk 10yrs after stopping
Small increased risk weighed against protective effects of cancer of ovaries/endometrium
68
Age risk with COCs
Over 35 years and smoker
Avoid over 50 years
Can be used up to 50 if no other risk factors present
69
Criteria to assess cautions/contraindications when prescribing COCs
UK Medical Eligibility Criteria
UKMEC
70
4 categories of UKMEC
1. No restrictions to use
2. Advantages of use outweigh risks
3. Risks generally outweigh advantages of use
4. Use would result in unacceptable risk or health (contraindicated)
71
Examples of contraindications in UKMEC 4 for COC
Severe/multiple risk factors for arterial disease
VTE
migraine with aura
Smoker > 15 per day and > 35 years
72
Risk factors for UKMEC 3 COC
1st degree relative < 45 years history of VTE
BMI > 35
Smoker <15 per day or stoped in last year and > 35
Symptomatic gall bladder disease
Controlled hypertension
Diabetes with nephropathy/retinopathy/neuropathy
Breastfeeding between 6 weeks and 6 months postpartum
73
temporary side effects of COC
breast tenderness
headaches
nausea
74
When can breakthrough bleeding (BTB) occur with a COC
in the first 3-6 months
75
What causes should be considered for breakthrough bleeding?
STIs
pregnancy
malabsorption
76
What to do if the side effects don't settle over the first 3 months?
try an alternative COC or an alternative form of contraception
77
What is migraine a risk factor for and what risks are increased?
cardiovascular disease
| - venous or arterial thromboembolism
78
Who have the greatest risk of ischaemic stroke with migraine?
women who have migraine with aura
79
migraine with aura and COCs UKMEC
contraindicated (UKMEC 4)
80
migraines without aura at initiation and COCs
UKMEC 2 (not contraindicated)
81
What is new onset of migraine without aura after intitation?
UKMEC 3
| benefits outweigh the risks
82
What should be considered in women who have migraine while taking COCs?
alternative contraception should be considered
| progestogen only contraceptive is more appropriate
83
reasons to stop COC immediately (8)
- sudden severe chest pain
- sudden breathlessness (or cough, blood sputum)
- severe pain in calf
- severe stomach pain
- severe neurological effects including severe headache, vision loss or sudden hearing disturbance
- hepatitis, jaundice, liver enlargement
- BP systolic > 160 mmHg, diastolic > 95mmHg
- detection of a risk factor
84
name of the combined contraceptive patch
Evra
85
What does Evra contain?
ethinylestradiol and norelgestromin
86
How should Evra patch be applied?
applied to clean, dry, lotion-free, healthy, hairless skin
87
Where not to apply Evra patch?
breasts, red/broken/inflammed skin
88
detached patch < 48hrs
re-apply the patch
| no additional precautions needed
89
detached patch > 48hrs or not sure when detached
- start new cycle of patch (new 1 week cycle and new day for starting)
- abstain/barrer for next 7 days
90
How often is Evra patch applied?
1 patch applied weekly for 3 weeks then 7 day patch free interval
91
MOA of traditional POPs
- alter cervical mucus making it more viscous and inpenetrable to sperm
- suppression of ovulation occurs in some women
92
% of ovultion suppression with traditional and desogestrel POP
traditional 60%
desogestrel 97%
93
MA of desogestrel only pill
- inhibits ovulation in 97% of cycles
| - can alter cervical mucus
94
2 types of POPs available in UK
traditional pills
| desogestrel pills
95
How is the traditional POP taken?
- 1 taken continuously without a break
| - 3hr window for missed pill
96
2 examples of traditional POP
Norethisterone 350mcg - Micronor and Noriday
| Levonorgestrel 30mcg - Norgeston
97
How is the desogestrel POP taken?
1 taken daily continuously without a break
| 12 hr window for missed pill
98
examples of desogestrel only pill
Desogestrel 75mcg - Cerazette, Aizea, Cerelle, Nacrez
99
When is desogestrel given 1st line?
- patients < 35yrs
| - compliance issues likely with tradidional POPs
100
When are POPs contraception of choice?
```
older women (up to 55yrs)
VTE (or Hx)
smokers
hypertension
valvular heart disease
diabetics
migraine sufferers
breast feeding
```
101
POP inititation on day 1-5
no additonal contraception required
102
POP initiation on day 6
additional precautions required - barrier/absitinence for 2 days
103
POP initiation postpartum
up to and including 21 days after - no additional contrapceiton required
104
POP initiation after termination/miscarriage
start immediatrly or up to 5 days after - no additional contraception required
105
POP missed pill < 3hrs (12hrs for desogestrel)
take missed pill asap
continue taking as usual even if 2 in one day
no additional contraception required
106
POP missed pill > 3 hrs (>12hrs for desogestrel)
take most recent pill (discard any others)
continue taking at usual time
use additional contraception/abstain for 2 days
EHC if SI within 2 days
107
disadvantages of POPs
- higher failure than COC
- doesn't control cycle as effectively as COC
- menstrual irregularities/bleeding common, settles with time
- small inc risk of breat cancer
- inc risk of ovarian cysts (reversible, no op)
108
if bleeding pattern unacceptable with POP
alternative contraception considered
| - COC if appropriate
109
UKMEC 4 contraindication for POPs
breast cancer
110
risk factors for UKMEC 3 for POP
```
PMH of breast cancer
severe cirrhosis
liver tumours
stroke/CHD
systemic lupus erythematosus with positive antiphospholipid antibodies
specific meds
```
111
What antibiotics are POPs not affected by?
non-enzyme inducing antibiotics like amoxicillan and doxycycline
112
short term treatment (< 2mths) of enzyme inducing drugs and POPs
stop POP and change to alternative contraception
OR
continue POP but abstain/barrier while taking and for 28 days after
113
long term treatment of enzyme inducing drugs and POPs
change to alternative contraception (barrier or progestogen-only injectable)
114
vomiting within 2 hrs of taking POP
take another asap
115
vomiting/diarrhoea for >24hrs while taking POP
follow instructions for missed pill
each day on vom/diarrhoea
abstain/barrier during illness and 2 days afterwards
116
2 brands of POP OTC
Hana
| Lovima
117
licenced indication for Hana
licenced for women of childbearing age
118
Hana price
£9.95 for 1 month
| £21.95 for 3 months
119
Lovima licencing
licenced for women of childbearing age including adolecents
120
Lovima price
£14.99 for 1 month
| £29.99 for 3 months
121
Supply of Hana/Lovima advice
first supply up to 3 months
| repeat supply up to 12 months
122
max supply for U18 of Hana/Lovima
maximum of 3 months can be supplied
123
switching from COC to POP
idealy complete COC pack omiting HFI
start POP next day (day 22)
no additional contraception is required
124
switching from traditional POP to COC
start COC the next day after POP
| need to abstain/barrier for 1st 7 days (9 days for Qlaira)
125
switching from desogestrel POP to COC
start COC next day after desogestrel POP
| no additional contraception required
127
examples of long acting reversible contraceptives (LARCs) (4)
1. progestogen-only injectable contraception
2. progestogen-only implant
3. progestogen-only intrauterine system (IUS)
4. copper intrauterine device (Cu-IUD)
127
How does progestogen-only injectable contraception work?
preventing ovulation
128
drug in progestogen-only injectable contraception
medroxyprogesterone acetate
129
How often is progestogen-only injectable administered?
every 12 weeks
130
failure rate of progestogen-only injectable contraception
6%
131
s/e of progestogen-only injectable contraception
weight gain
| small loss of bone density (recovers after discontinuation)
132
Is efficacy of progestogen-only injectable contraception affected by antibiotics/liver inducing enzymes?
no
133
When does fertility return after discontinuing progestogen-only injectable contraception?
can be delayed up to 1 year
134
Most common reason for discontinuing progestogen-only injectable contraception?
altered bleeding pattern and persistent bleeding
135
drug in progestogen-only implant
Etonogestrel
136
brand of progestogen-only implant
Nexplanon implant
137
How long does progestogen-only implant protection last?
3 years
138
failure rate for progestogen-only implant
low
| < 1 in 1000 over 3 years
139
How is progestogen-only implant inserted?
sub dermally by appropriate practitoner
140
s/e of progestogen-only implant
irregular bleeding
amenorrhoea
infrequent/prolonged bleeding
141
heavier women and progestogen-only implant
effectiveness can be reduced especially in the 3rd year
| earlier replacement may be considered
142
dely in return of fertility after progestogen-only implant
no delay
143
drug in progestogen-only intrauterine system (IUS)
Levonogestrel
144
How does Levonogestrel intrauterine system (LNG-IUS) work?
preventing endometroal proliferation
thickening of cervical mucus
suppressing ovulation in some women
145
4 examples of progestogen-only intrauterine system (LNG-IUS)
Jaydess
Levosert
Mirena
Kyleena
146
What does LNG-US stand for?
Levonogestrel intrauterine system
147
How long does progestogen-only intrauterine system last?
up to 5 years
| Jaydess 3 years
148
failure rate of progestogen-only intrauterine system
< 1%
149
s/e of progestogen-only intrauterine system
irregular bleeding and spotting in 1st 6 months
150
How does the copper intrauterine device work?
inhibits fertilisation by Cu's toxic effect on sperm and ova
| inhibits implantation due to local endometrial inflammatory reaction
151
What is 1st line for EHC?
Cu-IUD
152
benefits of Cu-IUD
no hormonal adverse effects
153
s/e of Cu-IUD
heavier bleeding
dysmenorrhoea
pain
154
duration of action of Cu-IUD
5-10 years
155
failure rate of Cu-IUD
< 1%
