Contraception Flashcards
Leading causative organisms for PID
- Chlamydia trachomatis
- Neisseria gonorrhoeae
- mycoplasmas and mixed anaerobes
Up to 70% of cases do not have an identifiable cause
How do COCs work to prevent pregnancy
prevent ovulation
thicken cervical mucus
alter the endometrial lining to make implantation less likely
When is the risk of COCP related VTE highest
highest in the first few months post initiation or following a break of >1 month
Risk reduces over time
Contraindications to COCP
VTE : clotting disorders, upcoming OT, >35yrs and >15 cigs
CVD Risk: prev CVD/IHD, diabetes, migraine w aura, HTN
Breast cancer - PMHx or or BRCA positive
Pospartum: >6/52 if breastfeeding, >3/52 if not
Age >50yrs
Cautioned in those with BMI >35
How to initiate a COCP
Start day 1-5 of cycle, no additional contraception required OR
Start at any point of the cycle, use condoms for the first 7 days
Usually start with 30-35mcg ethinylestradiol
*20 micrograms is associated with lower risks of VTE, stroke, and myocardial infarction BUT more risk of breakthrough bleeding.
7 days on, 7 days off, do a urine hcg 21 days post last unprotected
New advice re running pill packets
Lowers risk of pregnancy with no increased risk
If breakthrough bleeding persists for 3-4 days, stop pillsfor four days and then resume
If patients do not wish to omit the hormone-free interval completely, another option is to shortent the sugar pill period from 7 to 4 days instead
Link between cancers and COCP
Reduced risk of endometrial, ovarian and colorectal cancers
Increased risk of breast and cervical cancers
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Link between mood and weight with COCP use
Mood: variable, no clear evidence to support, use in cuation with significant depression/anxiety
Weight: no evidence to support this impacts weight
How to manage breakthrough bleeding when using a COCP
breakthrough bleeding is normal for the first 3 months of starting COCP
if ongoing after this consider increasing oestrogen to at leat 30-35mcg, or changing the progesterone
Women who smoke are at higher risk
How to POPs work to prevent pregnancy
- thicken cervical mucus (primary mechanism)
- Inhibit ovulation (50% of the time)
How to initiate a POP
Start day 1-5 of cycle, no additional contraception OR
Any day of cycle, use condoms for 48hrs
do a pregnancy test 3 weeks post last unprotected sexual event
2 funded POPs in NZ
Window of safety for taking
Microlut (Levonorgestrel 30mcg)
Noriday 28 Day (Norethisterone 350mcg)
Need to be taken within three hours of the regular dosing time each day
Contraindications to POPs
- Unexplained vaginal bleeding
- Severe liver disease
- Current breast cancer (low risk)
Use in caution in pts w prev IHD/stroke
Pros vs cons of POPS (vs COCPs)
Pros: minimal SEs, just as effective, can be taken immediately post partum
Cons:
- Small safety window (3 hours)
- Unpredictable bleeding patterns (due to the variable inhibition of ovulation), 50% normal cycles, 40% irregular cycles, 10% no menses. 70% breakthrough bleeding
Medications that can affect COCPs/POPS
CYP3A4 enzymes: rifampicin, rifabutin, carbamazepine, phenytoin, phenobarbital, ritonavir, St John’s wort, topiramate.
Laxatives if inappropriately used
What to do if a patient misses a COCP (up to 24hrs) or POP (>3hrs)
POP Cerazette/desogestrel (not funded) has a window of 12hrs
COCP:
- 1 pill: take as soon as it is remembered, and the next pill taken at the usual time, even if that means taking two pills at once.
- >2 pills: take as soon as it is remembered, use condoms for 7 days. If occuring in week 1/post sugar pills then give emergency contraception
POP:
- 1 pill: Take as soon as it is remembered. Do not take two together. Use condoms for 48hrs. Give emergency contraception if any unprotected sex
Vomiting and COCP
If vomiting occurs and less than two hours have passed since taking a COC or POP, another pill should be taken as soon as possible
What to know about contraception and the post partum period
IUD can be given <48hrs or >4 weeks post partum
POPs can be started whenever
COCPs: start >3/52 if not breastfeeding or >6/52 if breastfeeding
Women do not need contraception until 3 weeks PP
Lactational amenorrhoea method (LAM): 98% effective up to 6 months if FULLY breast-feeding (no supplementary feeds) and amenorrhoeic
Contraceptives - time until effective (if not first day period):
instant: copper IUD
2 days: POP
7 days: COC, depo, Jadelle, mirena
Emergency contraception options in NZ
Copper IUD: 5 days post UPS or 5 days post ovulation. Toxic to sperm, ibhibits fertilisation. Do not use if suspected STI.
Levonorgestrel : <72hrs, but take ASAP, ideally within 12 hours. Becomes less effective w time. Works to inhibit ovulation and thicken mucus, may not work if ovulation has already happened
- 1.5mg standard
- 3mg if BMI >26 or weight >70kgs
ellaOne (ulipristal acetate) is effective if taken within 120 hours of unprotected intercourse but not funded in NZ
Which contraception method is proven to be associated with weight gain?
Depo provera
Depo Provera contains?
How does it work?
Cons?
medroxyprogesterone acetate 150mg 12 weekly
Inhibits ovulation.
Secondary effects: cervical mucus thickening + endometrial thinning.
Cons
- delayed return to fertility (maybe up to 12 months)
- irregular bleeding (especially in 1st year, 50% become amennorheic after 12 mths)
- weight gain
- Reduced bone mineral density
Mode of action of these contraceptions
How does Jadelle (levonorgestrel) impact your pattern of nbleeding
Irregular bleeding for the first 6 months
After 6-12 months
- 30% have normal cycles
- 30% have irregular bleeding
- 20% have amennorhea
- 10% have heavy bleeding
