Contraception Flashcards
What is the world’s most widely used contraceptive method?
Condoms
Fertility awareness involves being able to recognise the signs + symptoms of fertility during a menstrual cycle, so that you can avoid/plan a pregnancy (family planning).
What 5 things in particular can a woman monitor?
Basal body temperature Cervical mucous Cervical position "Standard" days in cycle Breastfeeding
When must basal body temperature be taken when assessing the menstrual cycle? What is the expected increase in body temperature?
Before rising in the morning
Increase greater than 0.2’C sustained for at least 3 days following 6 days of a lower temperature
Describe cervical mucous immediately after a period
Low secretion, dry vagina
Describe cervical mucous leading up to ovulation
Moist, sticky, cloudy 8 days before
Wet, clear, slippery, stretchy 4 days before
Describe cervical mucous post-ovulation and its significance/relation with fertility
Thick and sticky
Fertility usually ended after day 3 of thick sticky mucous
What is the cervical position during fertility compared to when less fertile
High in vagina, soft and open when fertile; low in vagina, firm and closed when less fertile
In a 28 day menstrual cycle, which days are women most fertile?
Days 8-18
Breastfeeding can be very effective for fertility. What are the 3 criteria?
Exclusively breast feeding
Less than 6 months post-natal
Amenorrhoeic
What is the UK medical eligibility criteria (UK MEC)?
Summarises various medical conditions and their suitability for different forms of contraception
What is category 1 of the UKMEC?
No restriction on use of contraception
What is category 2 of the UKMEC?
Advantage of using contraception outweighs theoretical/proven risk to health
What is category 3 of the UKMEC?
Risk of using contraception outweighs benefit, thus use is not recommended without expert clinical opinion
What is category 4 of the UKMEC?
Unacceptable risk if contraception is used
The Pearl Index estimates failure rates of contraception - what is the formula?
[No. of accidental pregnancies x 1200]/total no. of months of exposure
What does LARC stand for?
Long-acting reversible contraception
List the main LARC methods used
Injection: Depo Provera (IM) Sayana press (SC) Intrauterine device (IUD) Intrauterine system (IUS) Implant
How does Depo Provera work? How often is it given?
Inhibits ovulation, thickens cervical mucous and thins endometrium
Given every 13 weeks
Depo Provera contains a complex which is a synthetic form of which hormone?
Progesterone
What chronic conditions may have implication when Depo Provera is used?
AFFECTS BMD Hypothyroidism Coeliac disease Rheumatoid arthritis Hyperparathyroidism IBD
When is conception most likely to occur?
Unprotected sex on the day of ovulation or the preceding 24 hours
When should Depo Provera be started without the need for using other contraception?
Up to and on day 5 of a normal cycle
When can Depo Provera be started beyond day 5 of a normal cycle?
Can be started at any other time provided the woman is reasonably certain she is not pregnant and has been using condoms or abstinent for at least 7 days
When can a woman be “reasonably certain” she is not pregnant?
Not had sex since last period
Consistently using reliable contraception
Is within first 7 days of onset of period
Is within 4 weeks post-partum
Is fully breast feeding, amenorrhoeic, <6m post-partum
Negative pregnancy test after 3 weeks since unprotected sex
List the main side effects of Depo Provera
Weight gain (increased appetite)
Delay in return of fertility
Irregular bleeding
Osteoporosis
Describe the composition of the LARC IUD
Non-hormonal T-shaped device made of copper and plastic
What is the significance of an IUD being made of copper? (how does this relate to its mode of action?)
Toxic to sperm and ova, therefore prevents fertilisation and causes inflammatory response in the endometrium
When should an IUD be started?
Any time in cycle if no UPSI in last three weeks
Since LMP and ongoing pregnancy excluded
When can an IUD be used as emergency contraception?
Up to 5 days after unprotected sex or up to 5 days after predicted date of ovulation
Pregnancy doesn’t implant first 5 days after ovulation
Describe the composition of the LARC IUS
T-shaped device with elastomere core that secretes progesterone into uterus
How does IUS work?
Makes implantation harder by thickening mucous and thinning endometrium
N.B. does not prevent fertilisation
When should an IUS be started?
Any time in cycle if no UPSI in last three weeks
Since LMP and ongoing pregnancy excluded
What are the contraindications to using an IUD or IUS?
Current pelvic infection Abnormal uterine anatomy Pregnancy Sensitivity to composition Gestational trophoblastic disease (molar pregnancy) Endometrial cancer
List some side effects of using an IUD or IUS
Heavy periods (though IUS may have lighter periods) Pain, infection Perforation Expulsion Failure to work! Ectopic risk with IUS
Describe the composition of the LARC implant
Non-biodegradable subdermal rod inserted above elbow that releases progestogen
How does a LARC implant work?
Inhibits ovulation
Thickens cervical mucous
Thins endometrium
When should a LARC implant be started? How long does contraception last?
Within first 5 days of menstrual cycle
3 years
List some side effects of LARC implant
Irregular bleeding
Weight gain
Acne
NV injury
List the LARC methods in order of lowest to highest Pearl index score
[highest = increased failure rate]
Implant, IUS, Depo Provera, IUD
What are the 3 main methods of non-LARC/short-acting contraception?
Combined hormonal contraceptive (CHC)
Progesterone-only pill (POP)
Emergency hormonal contraception (EHC)
List the non-contraceptive benefits of CHC
Reduce all of: Heavy menstrual bleeding Painful periods Acne Irregular periods Endometriosis Menstrual migraine
What are the 3 forms of CHC available?
Combined oral contraceptive pill (COC)
Combined transdermal patch (CTP)
Combined vaginal ring (CVR)
How does CHC work?
Inhibits ovulation via the HPO axis to reduce LH and FSH
Thickens cervical mucous
Thins endometrium
Describe a standard regime for taking COC
Take daily for 21 days then stop for 7 days, during which withdrawal bleed occurs
Use condom for 7 days after starting
Describe a standard regime for taking CTP
One patch worn for 1 week and reapplied weekly for further 2 weeks
Fourth week is patch-free to allow withdrawal bleed
Use condom for 7 days after starting
Describe a standard regime for taking CVR
Ring is placed and left in vagina for 21 days, then removed to allow withdrawal bleed
New ring inserted afterwards
Use condom for 7 days after starting
What factors may affect the effectiveness of CHC?
Impaired absorption (GI conditions )Increased metabolism (drug interactions) Forgetting
If a woman missed one pill of CHC, what should she do?
Take the last pill missed immediately
Continue taking the rest of the pack normally
If a woman missed 2 or more pills of CHC, what should she do?
Take the last pill missed immediately
Continue taking the rest of the pack normally
Use an additional contraceptive method for the next 7 days
What are the risks/side-effects of CHC?
Venous thrombosis
Arterial thrombosis
Alteration of clotting factors
Adverse effects on some cancers
CHC’s that contain which compounds have the lowest risk of venous thromboembolism?
Levonorgestrel
Norethisterone
Norgestimate[3rd generation COCs]
COC use can increase blood pressure. True/False?
True
Migraine with aura in COC users further increases the risk of what?
Stroke
Thus COC is contraindicated in these patients
CHC can aggravate breast cancer. If there is a personal history of breast cancer, what score on UKMEC is given?
4 - CHC contraindicated in these patients
CHC can aggravate breast cancer. If there is a family history of breast cancer, what score on UKMEC is given?
1 - CHC can be used
CHC can aggravate breast cancer. If there is a BRACA mutation, what score on UKMEC is given?
3 - CHC generally avoided
CHC offers protection against which cancers?
Ovarian and endometrial cancer
When should COC and POP be started?
COC started up to or on day 5 of cycle
Anytime after day 5 providing “reasonably certain” not pregnant and has been using condoms
What does the POP notably interact with?
Liver enzyme inducers
Which has the higher Pearl index - CHC or POP?
Neither! Both the same at 0.3%
How do barrier methods of contraception work?
Blocks sperm getting to female genital tract
How does female sterilisation work?
Blocks fallopian tubes
How does male sterilisation work?
Divides vas deferens (prevents passage of sperm)
List investigations to consider before prescribing contraception
BP
BMI
Cervical smear (check up-to-date)
PV to check uterine size if IUD being used
List the 3 main methods of emergency contraception
Intra-uterine copper IUD Oral LNGEC (Levonorgestrel) - progesterone only Oral UPAEC (Ulipristal acetate) - progesterone antagonist
When can oral LNGEC be used as emergency contraception?
Up to 72 hours post UPSI
Before ovulation
When can oral UPAEC be used as emergency contraception?
Up to 120 hours post UPSI
Before ovulation
What is it important to screen for before prescribing emergency contraception?
STI risk assessment
What is the significance of inhibiting ovulation with contraception?
No egg to be fertilised
State one advantage of taking POP over COC
Reduced side effect profile - no oestrogen
How long after emergency contraception can long-term contraception be started?
Intra-uterine copper IUD - immediately
Oral LNGEC - immediately
Oral UPAEC - wait 5 days
