Wk 11: Contraception in practice: Combined hormonal contraceptives Flashcards
What is the mechanism of action of the CHC’s?
- suppress LH + FSH production, inhibiting ovulation
- Inc cervical mucus
- Thins endothelium reducing implantation
How does CHC’s effect the endometrium?
- Oestrogen causes endometrium to proliferate + grow
- Progestogen prevents hyperplasia
- Resulting endometrium: thin, fragile + prone to bleeding
Give an example of a biphasic COC
Binovum
Give an example of a triphasic COC
Trinordiol
Qlaira
- Quadriphasic pill for heavy menstrual bleeding
- Start day 1 - 28 tabs
- Missed pill rule differ
Dianette
- Co-cyprindiol- cyproterone acetate + ethinylestradiol 2000/35
- Used for oral contraception + suffering from acne/hirsutism
- Inc risk venous thromboembolism
Monophasic COC initiation: Day 1 upto + including day 5 menstrual cycle
- No additional contraception
- Start day 1
Monophasic COC initiation: Day 6 of menstrual cycle onwards
- Additional precautions for 7 days after starting
- 9 qlaira
Monophasic COC initiation: Postpartum
- Upto + including day 21 postpartum
- If not breast feeding + no VTE risk
Monophasic COC initiation: termination/miscarriage
Immediately after or upto day 5
What is the action to take when one pill is late <24 hrs but <48hrs?
- Take late/missed pill asap
- Continue taking remaining pill at usual time
- No additional protection needed
What is the action to take when 2/more consecutive pills have been missed >48hrs?
- Take recent missed pill ASAP, any other missed = discarded
- Continue taking remaining pill at usual time
- Use additional contraception/avoid for 7 consecutive days: start continuously if runs btw HFI
What are the actions to take when on short term (<2 months) treatment for enzyme inducing antibiotics?
- Use alt barrier method whilst taking + 28 days after stopping
- Break through bleeding can occur
What are the actions to take when on long term (>2 months) treatment for enzyme inducing antibiotics?
Change alt method of contraception
Interactions
- Antiepileptics
- Lamotrigine
- Johns wort
What happens if vomiting occurs w/in 3 hrs of taking the pill?
Take another asap
What is the advise if vomiting/severe diarrhoea occurs for >24 hrs?
- Follow instruction for missed pill, each day of V/D = missed pill
- Avoid intercourse/barrier during illness + 7 days after
- If illness occurs last 7 tabs, omit pill free period + start next cycle
Outline the risks of age when taking COC
- Over 35 AND smoker
- Avoid >50 unless no risk factors
What are the contraindications of COC?
UKMEC category 4:
- VTE
- Migraine w/ aura
- Smoker ≥15 cigs per day + ≥35 years
What are some unwanted effects of COC?
- Tender breasts
- Headache
- Nausea
- Break through bleeding
- Weight gain
- Mood changes
Which UKMEC is migraine w/ aura?
4 - contraindicated
Which UKMEC is migraine w/o aura at initiation?
2
Which UKMEC is new onset of migraine w/o aura after initiation?
3
Outline the detached patch rules
Evra
- Partly detached <48hrs: re-apply patch
- Patch detached > 48hrs or not sure when detached: start new cycle (week 1 of day 1) + abstain/barrier for 7 days