Contraceptives Flashcards
(36 cards)
What is the first year failure rate for oral contraceptives based on typical use?
6-9%
What is the mechanism of action of combined estrogen-progestin OC?
- Negative feedback suppression of gonadotropin secretion
- Decreased production of FSH so follicles are not stimulated and not matured
- No LH surge at mid-cycle
What are the other contraceptive mechanisms of progestin?
- Makes cervical mucus thicker and more viscous, impairing sperm penetration
- Atrophy of endometrium leading to impaired implantation
- Uncoordinated contractions impairing sperm and ovum transport
Name the 5 common progestins in OCs.
Norethindrone, Levonorgestrel, Desogestrel, Drospirenone, Norgestimate
Which progestin has anti-mineralcorticoid activity?
Drospirenone
Which 2 progestin have the highest potency?
Levonorgestrel, Desogestrel
Which progestin has the most androgenic activity?
Levonorgestrel
Which progestin does not have any androgenic activity?
Dropirenone
Explain continuous use and give an example of OC that is used this way.
Fixed ratio of estrogen plus progestin for 84 days then low dose estrogen for 7 days. Seasonique
How is Seasonique different from Seasonale?
Instead of low dose estrogen for 7 days, you take inactive tablets for 7 days.
What are the 3 most serious adverse effects of OC use?
Venous thromboembolism, MI and stroke
Which progestin has a higher risk of VTE?
Dropirenone - 10/10,000 person
compared to 6/10,000 in all other OCs
T or F. The risk of VTE in pregnancy is higher than in OC users.
True. Risk of VTE in pregnancy = 29/10,000
Risk of MI and ischemic stroke is increased by __ fold in healthy, non-smoking women.
Two
What are 2 other CV actions of combined estrogen-progestin oral contraceptives?
1) Blood Coagulation - increase risk of blood clotting due to net pro-thrombotic effect
2) Small increase in BP - may increase risk of developing overt hypertension
What is the mechanism of OC induced BP increase?
Ethinyl estradiol activates Renin-angiotensin system. The effect is offset by decrease in renin production so BP elevation is small.
Why does drospirenone not increase BP?
It has anti-mineralcorticoid activity which inhibits the action of aldosterone. Normally aldosterone decreases sodium so water is retained but when this action is blocked water and sodium are excreted and does not increase ECF.
What is another effect of drospirenone’s anti-mineralcorticoid activity?
Potential to cause hyperkalemia in high risk patients (i.e. renal or adrenal insufficiency)
Effects of OC on blood lipids vary with ____ and _______ of the progestin.
Dose and androgenicity
T or F. There is a difference in rates of CHD between androgenic and non-androgenic preparations.
False, incidence of CVD is so low in women that we cannot tell if there is a difference between progestins.
Estrogens tend to increase (HDL/LDL) and decrease (HDL/LDL) cholesterol.
Increase HDL and decrease LDL
OC can increase the risk of which cancers?
Breast, cervical, and liver
OC can decrease the risk of which cancers?
Endometrial and ovarian
What are the contraindications to the use of combined OCs?
- Hx or actual VTE or CAD
- uncontrolled hypertension
- liver disease
- breast cancer
- abnormal vaginal bleeding
- pregnancy
- smoking in women over 35
- lactation (until 6 wks post partum)
