Contraception Flashcards
Methods of contraception available in UK
Combined hormonal contraception – COCP, combined transdermal patch & combined vaginal ring
Progestogen only contraception – POP, progestogen only implant and progestogen only injectable
Intrauterine contraception – copper intrauterine device (IUD) and levonorgestrel intrauterine system (IUS)
Barrier methods – male condom, female condom, diaphragm or cap
Sterilization methods – vasectomy and tubal occlusion
Natural family planning methods
Barrier methods
Male condoms, female condoms, diaphragms and caps
- Condoms: provide a barrier to the ejaculate, pre-ejaculate secretions and cervicovaginal secretions (reduces the risk of STIs)
- Diaphragms and caps: fit into the vagina to cover the cervix, must be used in conjunction with a spermicide
Combined hormonal contraceptives
Oral contraceptives, transdermal patch, vaginal ring
Act to inhibit ovulation – reduce the production of LH and FSH
Oestrogen – causes the endometrium to proliferate and grow
Progestogen – prevent hyperplasia of the endometrium by opposing the proliferative effects of oestrogen
COCP mechanism of action
Preventing ovulation
Progesterone thickens the cervical mucus
Progesterone inhibits the proliferation of the endometrium
Two types of COCP
Monophasic – same amount of hormone in each pill
Multiphasic – varying amounts of hormone to match the normal cyclical hormonal changes more closely
First line COCP
Recommend using a pill with levonorgestrel or norethisterone first line
Lower risk of VTE
Premenstrual syndrome first line
COCPs containing drospirenone (Yasmin) – first-line for premenstrual syndrome
Anti-mineralocorticoid and anti-androgen activity & may help with symptoms of bloating, water retention and mood changes
Continuous use may be more effective for premenstrual syndrome
Acne and hirsutism contraceptive treatment
COCPs containing cyproterone acetate (dianette) – can be considered
Has anti-androgen effects, however greater risk of VTE
Therefore, usually stopped three months after acne is controlled
COCP regimes
Equally safe and effective
21 days and 7 days off
63 days on and 7 days off
Continuous use without a pill-free period
COCP side effects and risks
Unscheduled bleeding is common in first three months
Breast pain and tenderness
Mood changes and depression
Headaches
HTN
VTE
Small increased risk of breast and cervical cancer
Small increased risk of MI and stroke
COCP benefits
Rapid return of fertility after stopping
Improvement in premenstrual symptoms, menorrhagia and dysmenorrhoea
Reduced risk of endometrial, ovarian and colon cancer
Reduced risk of benign ovarian cysts
COCP contraindications
Uncontrolled HTN
Migraine with aura
History of VTE
Aged > 35 and smoking > 15 cigarettes per day
Major surgery with prolonged immobility
Vascular disease/stroke
Ischaemic heart disease, cardiomyopathy or AF
Liver cirrhosis and liver tumours
SLE and antiphospholipid syndrome
(BMI>35 risks outweigh the benefits)
COCP starting the pill
Start on first day of cycle
Starting after day 5 of menstrual cycle requires extra contraception for the first 7 days
When switching from POP, can switch at any time but 7 days of extra contraception
COCP missed pill rules
Missing one pill (<72 hours since last pill was taken):
- Take missed pill as soon as possible
- No extra protection is required provided other pills before and after are taken correctly
Missing more than one pill (> 72 hours since last pill):
- Take the most recent missed pill ASAP
- Additional contraception needed until taken the pill regularly for 7 days straight)
- If day 1-7 of packet = need emergency contraception
- If day 8-14 of packet = no emergency contraception
- If day 15-21 of packet = no emergency contraception, skip pill-free period
COCP other considerations
Vomiting, diarrhoea and certain medications (eg. rifampicin) can all reduce effectiveness
Day of D/V – classified as a missed pill day
Stop COCP 4 weeks before a major operation – reduce the risk of thrombosis
POP
Only contains progesterone
Taken continuously, unlike the cyclical combined pills
Contraindicated in active breast cancer
POP types
1) Traditional progestogen-only pill – cannot be delayed by more than 3 hours
2) Desogestrel-only pill – can be taken up to 12 hours late
POP mechanism of action
Traditional – thickening the cervical mucus, altering the endometrium & making it less accepting of implantation, reducing ciliary action in the fallopian tubes
Desogestrel – inhibiting ovulation, thickening the cervical mucus, altering the endometrium, reducing ciliary action in the fallopian tubes
Starting the POP
Starting the POP on day 1-5 of menstrual cycle = women is protected immediately
Can be started at other times (pregnancy excluded) = additional contraception for 48 hours
POP side effects and risks
Unscheduled bleeding – amenorrhoea or irregular/prolonged/troublesome bleeding
Breast tenderness
Headaches
Acne
Increased risk of – ovarian cysts, small risk of ectopic pregnancy, minimal increased risk of breast cancer
POP missed pills rules
Take a pill as soon as possible, continue with the next pill at the usual time and use extra contraception for the next 48 hours of regular use
Emergency contraception is required if they have had sex since missing the pill
Episodes of D/V – managed as missed pills & extra contraception is required until 48 hours after the D&V settle
Progestogen-only injection
Given at 12 to 13 week intervals as an IM or subcut injection of medroxyprogesterone acetate
Can take 12 months for fertility to return after stopping injections
Progestogen-only injection contraindications
Active breast cancer
Ischaemic heart disease and stroke
Unexplained vaginal bleeding
Severe liver cirrhosis
Liver cancer
Can cause osteoporosis
Progestogen-only injection mechanism of action
Inhibit ovulation – inhibits FSH secretion by the pituitary gland, preventing the development of follicles in the ovaries
Thickening the cervical mucus
Altering the endometrium and making it less accepting of implantation
