Contraception & pregnancy Flashcards
MOA of progestins in CHC
- Reduce LH
- Prevent ovulation
- Thickens cervical mucus
- Reduce endometrial receptivity and sperm survival
MOA of oestrogen in CHC
- Reduce FSH
- Prevent follicular development
- Reduce irregular bleed
When is higher doses of ethinylestradiol recommended?
- 30-35 mcg/pill
- For those >70.5 kg
- Breakthrough bleeding esp in 1st half of cycle
Favourable progestins without significant androgenic effects
- Drospirenone (but with hyperkalemia)
- Cyproterone (not for contraception alone; VTE)
Androgenic side effects of CHC
Acne
Oily skin
Hirsutism
Depression
Increased appetite
Estrogenic side effects of CHC
N/V, bloating
Decreased libido
Weight gain
breast tenderness
Irritability
Increased TG levels
Progestogenic side effects of CHC
Headache
Breast tenderness
HTN
Depression
Decreased libido
Increased appetite
Increased LDL & TC
CHC contraindications
- Breastfeeding and <6 weeks postpartum
- > 35 y.o. and smokes >15 sticks a day
- SBP >160 or DBP >100 with end organ vascular disease of smoking
- Uncontrolled dyslopidemia with additional CV risk factors
- Diabetes with end organ vascular disease
- Current or h/o DVT
- Current or h/o IHD
- Current or h/o stroke
- Migrane with aura
- Migraine without aura + >35 y.o.
- Current breast cancer
Concerns for CHC
- VTE
- Breast and cervical cancer
- Stroke
- MI
DDIs with CHC
- Antiretrovirals (NNRTIs, PIs)
- ASMs (phenytoin, CPZ, barbiturates, topiramate, lamotrigine)
- Rifampicin
- Lamotrigine (increased risk of seizures when used as ASM monotherapy; less concerns if combined with VPA)
- Abx (backup for treatment duration and 7 days after)
Managing missed doses for CHC
<12 hours late: not affected
> 12 hours late:
- 1st week: back up for 7 days
- 2nd week: back up generally not needed
- 3rd week: start hormone free period immediately or skip the hormone free period and start new pack after this pack is finished
If >1 dose missed:
- Generally same strategy but consider emergency contraception if sexual intercourse in the past 5 days
Managing missed doses for POP
Norgestrel (Opill): >3 hours, backup for 2 days
Desogestrel (Cerazette): >12 hours, backup for 7 days
Drospirenone (Slinda): >24 hours, backup for 7 days
Emergency contraception
- Levonorgestrel (72 hours)
- Ullipristal (120 hours)
- Copper IUD (120 hours)
When to start CHC after emergency contraception?
- Levonorgestrel (right away; 7 days backup)
- Ullipristal (5 days later; 14 days backup or until next menstrual cycle)
When to inject Depo-Provera?
- By day 5 of menses initiation
- Immediately post-abortion
- Immediately postpartum (if no plans for breastfeeding)
- 6 weeks postpartum (if breastfeeding)