Contraception Flashcards
What is the most common form of medical contraception?
- Sterilised 28%
- Combined hormonal contraception (CHC) 25%
- Intrauterine methods (coil) 6%
- Progesterone only pill and progestogen only implants or injectable both 5%
Describe the characteristics of the ‘ideal’ contraception?
- Reversible
- All but sterilisation
- Effective
- None but vasectomy most then implant
- Free from side effects
- None
- Protective against STIs
- Condom is best
- Low maintenance
What is the Pearl index?
Number of contraceptive failures per 100 woman years of exposure
What can failure of contraception occur due to?
- Method failure
- Pregnancy despite correct use of method by user
- User failure
- Pregnancy because method not used correctly by user
What does LARC stand for?
Long acting reversible contraception
Why does LARC reduce failure rates?
Minimises user input
Which form of contraception has the lowest Pearl index?
IUS (intra-uterine system)
When is the highest chance of pregnancy curing the ovulation cycle?
When sex can cause pregnancy (if 26-32 day cycle and not on hormonal treatment):
- Likely ovulate day 12-18 (2 weeks before period)
- Egg survives 24 hours
- Most sperm survive less than 4 days (5% may survive 7 days)
- So highest chance of pregnancy occurs on day 8-19
How long can most sperm survive for inside the vagina?
- Most sperm survive less than 4 days (5% may survive 7 days)
What does CHC stand for?
Combined hormonal contraception
What are different forms of CHC?
- Pill
- Taken every day anytime in 24 hours
- Patch
- Changed weekly
- Vaginal ring
- Changed every 3 weeks
- Can be taken out for 3 hours out of every 24
How often is the CHC patch changed?
Weekly
How often is the CHC vaginal ring changed?
- Changed every 3 weeks
- Can be taken out for 3 hours out of every 24
What hormones are in CHC?
Is a combination of 2 hormones:
- Ethinyl estradiol (EE) and synthetic progesterone (progestogen)
- Stops ovulation, also affects cervical mucus and endometrium
What is the effect of CHC?
- Stops ovulation, also affects cervical mucus and endometrium
What is the standard regime of CHC?
Standard regime is 21 days with a hormone free week
What are some non-contraceptive benefits of CHC?
- Regulate/reduce bleeding
- Stop ovulation
- May help with premenstrual syndrome
- 50% reduced risk in ovarian and endometrial cancer
- Improve acne
What are some possible side effects of CHC?
- Breast tenderness
- Nausea
- Headache
- Irregular bleeding first 3 months
- Serious risks
- Increased risk venous thrombosis – DVT, PE (3x risk)
- Avoid if BMI>34, previous VTE, family history
- Increased risk arterial thrombosis – MI/stroke
- Avoid in smokers >35, history thrombosis, age > 50
- Increased risk venous thrombosis – DVT, PE (3x risk)
What does POP stand for?
Progestogen only pill
What is the administration of POP?
- Same time every day without a pill-free interval
What are the different types of POP?
- Desogestrel pill
- 12 hour window period
- Nearly all cycles anovulant (without ovulation), most bleed free
- Traditional LNG NET pill
- 3 hour window period
- 1/3 bleed free, 1/3 irregular, 1/3 regular
What are some contraindications for POP?
- History of breast cancer
- History of liver tumour
- NO increased venous or arterial thrombosis
What are some possible side effects of POP?
- Appetite increase
- Hair loss/gain
- Mood change
- Bloating or fluid retention
- Headache
- Acne
What is injectable progesterone?
Aqueous solution of the progestogen depomedroxyprogesterone acetate Depoprovera
What is injectable progesterone known as?
The jag
What is the adminion of injectable progesterone?
- 150mg 1ml deep IM injection into upper outer quadrant of the buttock every 13 weeks
What are the effects of injectable progesterone?
- Prevents ovulation
- Alters cervical mucus making it hostile to sperm
- Makes endometrium unsuitable for implantation
Are there any contraindications for injectable progesterone?
- Oestrogen free so few
What are some side effects/problems with injectable progesterone?
- Delay to fertility
- About 9 months
- Reversible reduction in bone density
- Problematic bleeding
- Weight gain
What is the only contraception with a causal effect on weight gain, delayed return of fertility and bone density?
Injectable progesterone
What is subdermal progestogen implant Nexplanon known as?
The rod
What is subdermal progestogen implant Nexplanon made from?
- Core
- 68mg etonogestrel (ENG)
- Membrane
- Ethinyl vinyl acetate (EVA)
What are the effects of subdermal progestogen implant Nexplanon?
- Inhibition of ovulation
- Effect on cervical mucus
What are advantages of subdermal progestogen implant Nexplanon?
- Can last 3 years and be removed at any time
- No user input needed
- No causal effect on weight
What are disadvantages of subdermal progestogen implant Nexplanon?
- 30% have prolonged bleeding
- May cause mood change more often than other progestogen only methods
What is intrauterine contraception known as?
The coil
What is intrauterine contraception a form of?
LARC
What are advantages of intrauterine contraception?
- Little user input
- Can be fitted for any age
- Effects/side effects immediately reversible when removed
What are possible side effects of intrauterine contraception?
- Small risk of infection in first 3 weeks <1:1000
- Perforation 1:1000
- Expulsion 5:100
- If conceives may be ectopic
What are contraindications for intrauterine contraception?
- Untreated pelvic infection
- Distorted endometrial cavity
What is the difference between IUD and IUS?
Intrauterine device - releases copper which is toxic to sperm
Intrauterine system - releases progesterone
What are the effects of copper IUD?
- Toxic to sperm
- Stop sperm reaching egg
- May prevent implantation of fertilised egg
What are possible side effects of copper IUD?
- May make periods heavier and crampier
What are advantages of copper IUD?
- Can last 5-10 years depending on type
- Hormone free
- Not a contraindication to MRI
What are the effects of levonorgestrel IUS?
- Affect cervical mucus and endometrium, most woman still ovulate
- Stop fertilisation of egg
What are advantages of levonorgestrel IUS?
- Low circulating progestogen levels compared with pill/implant/injection
- Reduce menstrual bleeding after up to 4 months initial irregular bleeding
What are different types of levonorgestrel IUS?
- Mirena
- 5 years contraception
- More hormone than other 2
- Kyleena
- 5 years contraception
- Jaydess
- 3 years contraception
Which type of levonorgestrel IUS contains the most hormone levels?
Mirena
What are different kinds of emergency contraception?
-
Copper IUD
- Most effect option
- Needs to be fitted before implantation, so within 120 hours of sex
- 1/100 failure rate
-
Levonorgestrel pill “Levonelle”
- Take within 72 hours
- 2-3/100 failure rate
-
Ulipristal pill “Ellaone”
- Take within 120 hours
- 1-2/100 failure rate
- More contraindications, such as breast feeding, enzyme inducing drugs, acid reducing drugs
How long after sex must copper IUD, levonorgestrel pill, and ulipristal pill be taken?
Copper IUD - 120 hours
Levonorgestrel pill “Levonelle” - 72 hours
Ulipristal pill “Ellaone” - 120 hours
Once contraception has been started, during what phases of the ovulation cycle does it work in the beginning?
- Start first 5 days of cycle
- Immediate cover
- Other times
- Need condoms/abstain for next 7 days
When can you get pregnant after delivery, miscarriage and abortion?
Delivery - 21 days
Miscarriage - 5 days
Abortion - 5 days
For how long is breast feeding a contraceptive?
Breast feeding is contraceptive for first 6 months:
- Breast feeding woman can use any kind of contraception
What are examples of common drug interactions with contraception?
- Enzyme inducing drugs
- Such as carbamazepine, topiramate, rifampicin
- Increases the metabolism of progestogen and oestrogen, reducing effectiveness of combined pill, patch, ring, POP and implant
- Injectable progestogens and copper or levonorgestrel IUD are not affected
What are some barrier methods of contraception?
- Diaphragm
- Cervical cap
- Male condom
- Female condom
What is the most common method of female sterilisation?
Laparoscopic sterilisation = filshie clips applied across tube to block the lumen
What are risks of female sterilisation?
- Irreversible so risks regret
- Failure rate 1/200
What are advantages of female sterilisation?
- No effect on periods/hormones
- Reduces ovarian cancer risk
What happens in a vasectomy?
Vas deferens divided and ends cauterised small incision midline scrotum:
- Under local anaesthetic so most done in primary care
What are advantages of vasectomy?
- No effect on testosterone or sexual function
- No increased risk testicular or prostate cancer
What are disadvantages of vasectomy?
- Takes 4-5 months to be effect
- Failure rate 1/2000
- Irreversibility
- 1:100 testicular pain
What percentage of UK woman have an abortion?
1/3 UK woman will have an abortion:
- Most common age group is 20-24
- Numbers falling
- 90% are under 12 weeks
What are the clinicians rights and responsibilities in regards to abortion?
- Right to refuse
- Ensure woman can access abortion care if they refuse
What ligislation directs abortions?
Abortion Act 1967
What cirriculum must be achieved for an abortion to be allowed under the Abortion Act 1967?
- 2 doctors sign to support woman’s request
- Continuing pregnancy has grave risk to life of woman, more than if is terminated
- Necessary to prevent grave injury to physical or mental health of woman
- Substantial risk that if child was born it would suffer physical or mental abnormalities as to be seriously handicapped
What occurs in a clinic consultation about abortion?
- Scan for gestation and viability
- Medical history
- Risk VTE, bleeding, contraceptive eligibility
- Circumstances
- Reason for considering abortion, check coercion or gender based violence
- Discuss methods and what to expect
- Contraception for afterwards
- Investigations
- FBC/Rhesus group
- Vaginal swab for chlamydia and gonorrhoea
- STI bloods offered
What are the different forms of terminating a pregnancy?
-
Surgically
- Can be done from weeks 5-12
- Complications
- Perforation 4:1000
- Infection
-
Medically
- Can be done weeks 5-24
- Mifepristone oral antiprogestogen tablet
- 36-48 hours later misoprostol initiates uterine contraction which opens cervix and expels pregnancy
- Complications
- Failure 1:100<8 weeks and 8:100 > 12 weeks, needs surgery to complete
- Infection
- Can be done at home
During what weeks is a surgical abortion possible?
Weeks 5-12
What are possible complications of a surgical abortion?
- Perforation 4:1000
- Infection
During what weeks can a medical abortion be done?
- Can be done weeks 5-24
What medication is given for a medical abortion?
- Mifepristone oral antiprogestogen tablet
- 36-48 hours later misoprostol initiates uterine contraction which opens cervix and expels pregnancy
What are possible complications of medical abortions?
- Failure 1:100<8 weeks and 8:100 > 12 weeks, needs surgery to complete
- Infection
What are some long term effects of abortion?
- No effect on future fertility
- No effect on cancer risks
- Emotional effects
