15) Sexual & Reproductive Health - Contraception Flashcards
Proportion of women using oral contraception in last year
1/3
Different generations of progestogens in CHC
First generation: Norethisterone
Second generation: LNG
Third generation: Desogestrel, gestodene, norgestimate
Other: Drospirenone, dienogest, nomegestrol
Main mechanism of action of combined hormonal contraceptives
Prevention of ovulation
When to start CHC?
(1) D1-D5 of natural menstrual cycle (or D1-D5 post early pregnancy loss) without additional precautions
(2) “Quick start” at any other time (with additional precautions for 7 days) provided reasonably certain not pregnant OR UPT is negative and follow up UPT done 21 days after UPSI.
When to start CHC after EC?
Immediately after Levonelle.
5 days after EllaOne.
How to switch to CHC from another method?
- From another CHC: Start on day after last active dose.
- Desogestrel POP: Start immediately with no additional precautions
- Traditional POP: Start immediately but need additional precautions 7d
- Mirena: Start any time but use additional contraception for 7d.
- Cu-IUD: Up to D5 of menstrual cycle without precaution or any time with 7d additional precautions
Effectiveness of COCP
- Perfect use: 0.3% failure
- Typical use: 9% failure
When is a COCP classed as missed?
If not taken in 24h after it should have been
Effect of enzyme inducing drugs on CHC
Reduced effectiveness for duration of treatment and up to 28 days after
Interaction of lamotrigine and CHC
Lamotrigine may be less effective
Advice re: D&V with CHC
Follow “missed pill” advice if vomiting occurs within 3 hours of COC or severe diarrhoea occurs for 24 hours.
“Missed pill” advice for COCP, vaginal ring and patch
(1) If late restarting HFI (any number of pills, ring, patch):
- Emergency contraception if UPSI during HFI
- Take most recent missed pill and then continue pills at usual time
- Additional precautions for 7 days
- Consider 3/52 PT
(2) If miss pills during week 1:
ONE PILL ONLY/RING removed <48h/PATCH <48h:
- No EC required
- Take most recent missed pill and then continue pills at usual time
- No additional precautions required
TWO OR MORE PILLS/RING removed >48h/PATCH >48h:
- Emergency contraception if UPSI during HFI/week 1
- Take most recent missed pill and then continue pills at usual time
- Additional precautions 7 days
- Consider 3/52 UPT
(3) If miss pills during week 2/3:
ONE PILL ONLY/RING removed <48h/PATCH <48h:
- No EC required
- Take most recent missed pill and then continue pills at usual time
- No additional precautions required
TWO OR MORE PILLS/RING removed >48h/PATCH >48h:
- No EC required
- Take most recent missed pill and then continue pills at usual time
- Additional precautions 7 days
- If during week 3 - omit HFI
Precautions for accidental continued use of the same combined hormonal vaginal ring beyond 3 weeks
3-4 WEEKS:
- EC not required if ring consistently in place D21-D28
- Start HFI or insert new ring
- No additional precautions required
4-5 WEEKS:
- EC not required if ring consistently in place D21-D28
- Omit HFI and insert new ring
- Additional precautions 7 days
> 5 WEEKS:
- EC if UPSI during week 5 or later
- Omit HFI and insert new ring
- Additional precautions 7 days
- Follow up UPT
What percentage of women experience breakthrough bleeding with CHC?
10-20% per cycle which is likely to improve over first 3-4 months.
Return to fertility with CHC
99% return to spontaneous menstruation (or become pregnant) within 90 days of stopping CHC. Majority ovulate within 1 month.
1st line COCP
<30 microgram ethinylestradiol with LNG/NET
Risk of VTE with CHC
- Risk is increased 3-5 fold
- Non-users 2 per 10,000/year. CHC 5-12 per 10,000/year.
- Lower than pregnancy!
- Highest in months immediately after insertion or when restarting after break > 1 month (risk reduces over first year of use and then remains stable)
Effect of progestogen type on VTE risk
No CHC: 2 per 10,000 per year
LNG/NET/norgestimate: 5-7 per 10,000
Etongestrel/norelgestromin: 6-12 per 10,000
Drospirenon/gestodene/desogrestrel/co-cypindiol: 9-12 per 10,000
Risk of arterial thromboembolic disease with CHC
- Increased risk of MI and ischaemic stroke
- Risk higher with increased oestrogen doses but does not vary according to progestogen type
Risk of breast cancer with CHC
- Current use carries small increased risk (RR 1.2) which reduces with time after stopping (normal by 5 years)
Risk of cervical cancer with CHC
- Current use for >5 years associated with increased risk which reduces after stopping and is normal at 10 years
Advice for CHC and altitude
Avoid if spending > 1 week at altitude > 4500m
Advice for CHC and major surgery
Switch method at least 4 weeks prior to planned major surgery or expected period of limited mobility
Efficacy of male and female condoms
Male condoms: Perfect use 2% failure, typical use 18% failure
Female condoms: Perfect use 5% failure, typical use 21%
Risk of HIV transmission following exposure to known HIV positive individual for different sexual behaviours
Receptive anal intercourse 1%
Receptive vaginal intercourse 0.1%
How to use diaphragm/cap?
- Use spermicide
- Reapply spermicide before sex repeated of if it has been in situ >3h before sex
- Leave in situ 6 h following sex (max duration latex diaphragms 30h, silicone cervical cap up to 48h)
Efficacy of diaphragm/cap
Perfect use: 6% failure
Typical use: 12% failure
Recommendations re: spermicide
Use with diaphragm/cap
Condoms lubricated with N-9 not recommended (repeated and high dose use associated with increased risk of genital lesions from epithelial disruption)
Recommendations re: lubricants
Water/silicone based preparation recommended
Use of lubricant recommended for anal sex to reduce risk of condom breaking
UK-MEC 3 conditions for diaphragms/caps
- High risk of HIV
- Known HIV/AIDS
- History of TSS
- Sensitivity to latex
- Not suitable < 6 weeks postnatal
- Avoid during menstruation
Effect of BMI on combined contraception
No association between BMI and oral effectiveness although it may be reduced by bariatric surgery.
Patch may be less effective if weight >90kg.
Main mode of action of progestogen only pills
Increased volume and viscosity of cervical mucus
What percentage of people does the POP inhibit ovulation in?
60% traditional
97% desogestrel
Failure rate of POP
Typical use: 9%
Perfect use: 0.3%
(Same as COCP!)
Percentage of ectopic pregnancies if pregnancy on POP
10%
When is a traditional POP classed as a missed pill?
> 3h late (>27h since last pill)
When is the desogestrel POP classed as a missed pill?
> 12h late (>36h since last pill)
Enzyme inducing drugs and POP
Reduce efficacy
What to do if pill missed on POP?
Take missed pill + next pill. Use additional precautions 2 days. EC if UPSI since missed pill and within 48h of restarting.
How long to use additional precautions for with POP during any uncertain transitions/starting points etc?
2 days
What is the bleeding pattern reported after 12m DSG POP?
50% Amenorrhoea
40% 3-5 bleeding/spotting episodes
10% >6 bleeding/spotting episodes
When do you need additional precautions when switching from implant?
None if within 3 years since insertion
When do you need additional precautions when switching from depo?
None if within 14 weeks of last injection
UK-MEC criteria for POP
4: Current breast cancer
3: New IHD, new stroke/TIA, severe cirrhosis, hepatocellular carcinoma, past breast cancer.
Licensed duration for progestogen only implants
3 years
Primary mode of action of progestogen implants
Prevent ovulation
Failure rate of progestogen implants
0.05%
Bleeding pattern with implant
<1/4 will have regular bleeds.
1/3 infrequent bleeds
1/4 prolonged/frequent bleeding
1/5 no bleeding
When to switch arm for implant?
After 2 consecutive implants due to theoretical risk of skin atrophy.
Enzyme inducing drugs and implant?
Reduce efficacy
UK MEC for implant
4: Current breast cancer
3: New IHD, new stroke/TIA, severe cirrhosis, hepatocellular carcinoma, past breast cancer.
(They are all the same as for POP) + Unexplained vaginal bleeding.
Additional precautions during times of uncertainty with implant
7 days
What to do if impalpable implant?
Use additional precautions.
USS - if not visualised on USS then manufacturer can send ENG blood sample to lab. If ENG detected then need MRI, if not detected <3y from insertion then it’s not in the body!
Effect of bent/broken implants
Doesn’t affect efficacy
Management of problematic bleeding on implant
Could add in COCP
Routes of progestogen injections
Depo-Provera: IM
Sayana-Press: SC
Main mechanism of action of progestogen injections
Inhibition of ovulation
Failure rate of progestogen injections
Typical use 6%
Perfect use 0.2%
UK-MEC for progestogen injections
4: Current breast cancer
3: Past breast cancer, liver stuff, stroke, IHD, unexplained vaginal bleeding, multiple risk factors for CVD, vascular disease
Changes to bleeding pattern with progestogen injection
Trend towards less bleeding and amenorrhoea with increased duration of use
Effect of progestogen injection on weight
Associated with weight gain, especially in girls <18y with BMI >35.
Women who gain >5% baseline body weight in first 6m likely to continue gaining weight.
Other S/E of progestogen injections
Injection site reactions
Hair loss
Headaches
Reduced BMD
Progestogen injection in sickle cell
May reduce severity of sickle crisis pain
How long for fertility to return after depo?
Up to 1 year
Dosing interval for depo
13 weeks. *but no additional precautions needed up to 14w
How long additional precautions for with depo during uncertain times?
7 days
Mirena “dose”
52mg. Releases 20 micrograms per day.
Jaydess “dose”
13.5mg. Releases 14 micrograms per day.
Implant “dose”
60mg. Releases 60 micrograms per day.
Primary mechanism of action of copper IUCD
Inhibits fertilisation
Primary mechanism of action of mirena
progestognenic effect on endometrium
What percentage of women with mirena still ovulate?
75%
What is the most effective type of copper coil?
T shape containing 380mm2 of copper with additional copper bands on transverse arms.
Criteria to be “reasonably sure” someone isn’t pregnant
Not had intercourse since last period. UPT negative >3w since last UPSI. Reliably using contraception. Within 7 days of cycle. (<4 w PP if not BF, <6m PP if fully BF and amenorrhoea, 7d postabortion/miscarriage)
Failure rate of copper IUD
Perfect use 0.6
Typical use 0.8
Failure rate of mirena
0.1
When is additional contraception required during uncertain times for mirena/copper coil?
Mirena - 7 days
Copper coil - Not needed
When to put coil in following emergency contraception?
Cu-IUD if still in time window otherwise neither should be inserted until pregnancy excluded (-ve UPT >3w after UPSI)
Risk of PID after IUC insertion
0.5%
Persistent irregular bleeding at 1 year after mirena
20%
Risk of ectopic pregnancy with coil
1 in 1000 at 5 years
if pregnancy occurs up to 50% risk ectopic
Risk of expulsion
1 in 20
Risk of perforation
2 per 1000
Discontinuation of IUC due to pelvic pain/cramping
30%
Risks of pregnancy with coil in situ
Abortion, PTL, sepsis
When to remove coil?
Prior to 12w once pregnancy location confirmed
When should you consider removing coil in PID if no improvement seen after?
72 hours
Failure rate female sterilisation
0.5%
Failure rate male sterilisation
0.05%
When is male sterilisation classed as failure?
Do first sample 12w because if azoospermia then all good :)
If motile sperm in sample 7 months post-op then procedure has failed.
Prevalence of female sterilisation worldwide
19%
Prevalence of male sterilisation worldwide
2.5%
Regret rates in women
Up to 25%
Reversal rates in men
2%
Failure rate of fertility awareness methods
Typical use 24%
Perfect use 0.4%
What should women who want to swap from hormonal contraception to fertility awareness methods do?
Wait until regular cycle returns and have at least 3 normal cycles before relying on new method.
Lifespam of ovum and sperm
24h and 7d
How does basal body temperature method work?
Following ovulation progesterone increases BBT until menstruation.
Post-ovulatory infertile phase of the cycle starts once temperature on 3 consecutive days are minimum of 0.2 degrees higher than all of the previous 6 days.
Then safe until next menses!
How can cervical secretions be used as contraception?
Avoid intercourse on any days with cervical secretions present or when they were present the day before.
How is the calendar used to control fertility?
Record cycle length for 12 months and fertile days are from shortest cycle length-20 to longest cycle length-10 e.g. 8-19.
What does the symptothermal method involve?
Combines cervical secretions, BBT and calendar.
Failure rate of withdrawal method
4% perfect use
22% typical use
What is required for lactational amenorrhoea to be effective as contraception?
Fully or nearly fully BF day and night.
No long intervals between feeds (>4h day, >6h night)
Amenorrhoea
Less than 6m postpartum
Efficacy of LAM as contraception
2%
What percentage of women have resumed sexual activity by 6 weeks postpartum?
50%
What proportion of term pregnancies are unplanned at the time of conception?
1/3
What proportion of women presenting for abortion had conceived within 1 year of childbirth?
1/13
What proportion of women are exclusively breastfeeding at 6-8 weeks?
29%
Non-attendance rate if patient has to return postpartum for coil fitting
50%
Expulsion rate with PPIUC insertion
17%
Risk of perforation in breastfeeding women compared to non-breastfeeding
6 x increased risk up to 36 weeks postpartum
What proportion of women won’t have visible coil threads after CS insertion?
50%
What should breastfeeding women do if they have ellaone EC?
Temporarily discontinue BF and express milk 1/52
