Contraception Flashcards
What are monophasic pills?
Same hormone concentration throughout all pills
Types of monophasic pills? (COC)
21 day cycle 1 OD for 21 days, 7 day break
ED pills: 21 hormonal pills then 7 placebo
Zoely 24+4
What is in COC?
Ethinylestradiol (EE) and progestogen
What are phasic COCs?
Varying hormone concentrations throughout cycle
biphasic - 2 concs
triphasic - 3 concs
Examples of phasic COCs?
21 day phasic cycle
28 day phasic cycle - Qlaira 26+2, logynon
What is POP?
Progestrone only Pill
Characteristic of POP cycles?
no pill free period - taken for 28 days
Examples of POP?
traditional - norethisterone 350mcg (higher doses are therapeutic)
newer - desogestrel
What is CHC?
Combined hormonal contraception - non oral
What is POC?
Progestrogen only contraception - non oral
Examples of CHC?
contraceptive patch, vaginal ring
How contraceptive patch is used?
1 patch per week for 21 days, then 7 days patch free
How vaginal ring is used?
1 ring for three weeks, then 7 days free
Examples of POC?
Depo injection, contraceptive implant, IUS
Frequency of contraceptive injection?
150mg IM every 8-12 weeks
104mg subcut every 13 weeks (more common)
What hormone is in the injection?
Medroxyprogesterone
What hormone is in the contraceptive implant?
etonogestrel
What hormone is in the IUS?
levonorgestrel
How do CHCs prevent pregnancy?
synthetic oestrogens inhibit FSH by negative feedback no follicular development
inhibit ovulation
thickened cervical mucus and altered endometrium
How to POCs prevent pregnancy?
Suppression of ovulation, thickened cervical mucus, delayed ovum transport, hostility of endometrium,
Efficacy of CHC and POC?
99.7% with perfect use, 92% with typical use
Efficacy of contraceptive pills?
99% perfect use, 91% typical use
Efficacy of vaginal ring, patch etc?
99% perfectuse, 91% typical use
Efficacy or LARC?
All 99% - expect typical use of injection 94%
less user dependent
Efficacy of non-hormonal methods?
male condom - up to 98% (82% typical)
female condom - up to 95% (79% typical)
Natural family planning - up to 98%
Diaphragm: 92-96% perfect (71-88% typical)
Sterilisation: male - 1/2000, female - 1/2-500
What is lactational amenorrhoea?
breastfeeding can be used as contraception, up to 98% effective
Criteria for LAM to be effective?
- fully breastfeeding (or nearly)
- baby is under 6 months
- amenohrrhoeic
risk of pregnancy increases once any of these changes, regardless of other factors
What determines contraceptive choice?
UKMEC categories for contraindications/DDIs, other than that patient choice
Things for patients to consider when choosing contraception?
efficacy, risks, pros and cons, advice on missed doses (user dependence and adherence)
What is quick starting contraception?
Started on any day, not the first day of the cycle. Additional precautions required
Advantages of COC?
- Periods lighter, more regular, less painful
- reduced acne, functional ovarian cysts, benign ovarian tumours
- decreased risk of uterine, ovarian and colon cancer
Disadvantages of CHC?
- minor ADRs (nausea, breast tenderness, loss of libido, breakthrough bleeding)
- EE increases angiotensin (BP)
- EE increases HDL and decreases LDL - progesterone does opposite
- EE decreases antithrombin but increases some other clotting factors (VTE, MI, stroke)
- breast and cervical cancer risk
Advantages of POC?
- high efficacy
- suitable when CHC isn’t
- reduced risk of endometrial cancer, benign breast disease, uterine fibroids, anaemia
Definition of a missed pill for COC?
> 24 hours late
Zoely/Qlaira - >12 hours
critical at start and end of cycle as extends pill free period
When is EHC indicated for COC users?
2 or more pills missed within 7 days and UPSI
Zoely and Qlaira: 1 pill missed
Definition of a missed pill for POP?
> 3 hours late for norethisterone, 12 hours for desogestrel
When is EHC indicated for POP users?
1 missed pill and UPSI occurring before 2 pills taken correctly
Counselling for POP users regarding missed pills
If one pill missed, use precautions for 2 days
UKMEC category 1 definition?
No restriction of use on the method
UKMEC category 2 definition?
Advantages of using the method generally outweight the risks
UKMEC category 3 definition?
Theoretical or proven risks usually outweight the benefits. Requires expert/specialist judgement. not recommended unless no suitable alternative
UKMEC category 4 definition?
Unacceptable health risk if the method is used
UKMEC category conditions
- breastfeeding women <6 weeks pp
- > 35y + 15 cigs a day
- multiple CVS risks
- consistently elevated BP
- vascular disease & history of VTE, IHD, stroke
- migraine with aura
- current breast cancer
- Diabetes with nephropathy, retinopathy or neuropathy
- Benign hepatocellular adenoma and malignant hepatoma
- Systemic lupus erythematosus
Who has increased risk of MI with contraception?
current COC users who smoke
Stroke risk and contraception?
normotensive, non-smoking COC users:
- no increased risk of hemorrhagic stroke
- 1.5x higher risk of ischaemic stroke
VTE risk and contraception?
non pregnant women - 2 cases per 10,000 / year
pregnant women - 6 cases per 10,000 pregnancies / year
When should CHC be stopped immediately?
- sudden severe chest pain (even if not radiating to left arm)
- sudden breathlessness (or cough with blood-stained sputum)
- unexplained swelling or severe pain in calf of one leg
- severe stomach pain
- serious neurological effects including unusual severe, prolonged headache especially if first time or getting progressively worse or sudden partial or complete loss of vision or sudden disturbance of hearing or other perceptual disorders or dysphasia or bad fainting attack or collapse or first unexplained epileptic seizure or weakness, motor disturbances, very marked numbness suddenly affecting one side or one part of body
- hepatitis, jaundice, liver enlargement;
- blood pressure above systolic 160 mmHg or diastolic 95 mmHg; (in adolescents stop if blood pressure very high)
- prolonged immobility after surgery or leg injury
When can COC be started and what precautions are necessary?
Day 1 of cycle is ideal
Day 1-5 no precautions needed
Day 6 onwards (quick starting), precautions for 7 days