Fertility Control - Combined Oral Contraceptive Pill (COCP) Flashcards
Efficacy of COCP.
99% effective with perfect use but 91% effective with typical use.
UKMEC4 of COCP (9).
- Uncontrolled Hypertension (160 | 100).
- Migraine with Aura.
- History of VTE.
- Above 35 and Smoking 15+ Per Day.
- Major Surgery with Prolonged Immobility.
- Vascular Disease or Stroke.
- Ischaemic Heart Disease, Cardiomyopathy or AF.
- Liver Cirrhosis and Liver Tumours.
- SLE or Anti-Phospholipid Syndrome.
UKMEC 3 of COCP (6).
- BMI above 35.
- Immobility e.g. Wheelchair Use.
- Diabetes Mellitus.
- Family History of VTE Under 45.
- Gallbladder Disease.
- BRCA1/2 Genes.
Mechanism of Action of COCP (3).
- Preventing Ovulation (Primary Mechanism).
- Thickens Cervical Mucus (Progesterone).
- Inhibits Proliferation of Endometrium to Reduce Chance of Successful Implantation (Progesterone).
How does the COCP prevent ovulation?
Oestrogen and Progesterone cause negative feedback on HPG axis to suppress release of GnRH, LH and FSH so less LH and FSH will prevent ovulation.
Aetiology of Withdrawal Bleed (2).
- Lining of the endometrium is maintained in a stable state while taking the pill.
- If stopped, the lining breaks down (due to fall in hormone concentration).
What are monophasic pills and what are multiphasic pills?
Monophasic - same amount of each hormone in each pill.
Multiphasic - varying amounts to match the normal cyclical hormonal changes.
Examples of Monophasic COCPs (5).
- Microgynon - Ethinylestradiol + Levonorgestrel.
- Loestrin - Ethinylestradiol + Norethisterone.
- Cilest - Ethinylestradiol + Norgestimate.
- Yasmin - Ethinylestradiol + Drospirenone.
- Marvelon - Ethinylestradiol + Desogestrol.
Recommendations of COCPs (3).
- 1st Line (due to lower risk of VTE) : Microgynon or Loestrin.
- Premenstrual Syndrome : Drosperinone (Yasmin) - due to anti-mineralocorticoid/anti-androgen activity e.g. bloating, water retention and mood changes but continued use (not cyclical).
- Acne and Hirsutism : Cyproterone Acetate (Dianette) but 1.5-2x increased risk of VTE so usually stopped once acne is controlled 3 months later.
Common Regimes for COCPs (3).
- 21 days on and 7 days off.
- 63 days on (3 packs) and 7 days off (‘tricycling’).
- Continuous use without a pill-free period.
Starting COCP :
- Before Day 5.
- After Day 5.
- If before day 5 of menstrual cycle, it provides protection immediately so no additional contraception is required.
- If after day 5, requires extra contraception i.e. condoms for the first 7 days.
Switching COCPs :
- Between COCPs.
- From a Traditional POP to a COCP.
- From a Desogestrol POP to a COCP.
Between COCPs : Finish Pack 1 before immediately switching with no Pill-Free Period.
From a Traditional POP - Switch at any time but again 7 days of extra contraception is required.
From Desogestrol POP - Switch at any time and no additional contraception is required.
Missed COCPs :
- What is a Missed Pill?
- Missed on Day 1-7.
- Missed on Day 8-14.
- Missed on Day 15-21.
Missed Pill : Pill is more than 24 hours late.
Missed on Day 1-7 and UPSI : Emergency Contraception.
Missed on Day 8-14 and UPSI : NO Emergency Contraception.
Missed on Day 15-21 and UPSI : NO Emergency Contraception and Skip Pill-Free Period.
What do you do if you miss a COCP?
If less than 72 hours after last pill, take missed pill ASAP (even 2 a day) and no extra protection. If more than 72 hours after last pill, take most recently missed pill ASAP (even 2 a day) and extra protection for 7 days straight.
When would intercourse be safe during the Pill-Free Period?
If the next pack is started on time.