Contraceptives

Question 1

What is the first year failure rate for oral contraceptives based on typical use?

Answer 1

6-9%

Question 2

What is the mechanism of action of combined estrogen-progestin OC?

Answer 2

• Negative feedback suppression of gonadotropin secretion
• Decreased production of FSH so follicles are not stimulated and not matured
• No LH surge at mid-cycle

Question 3

What are the other contraceptive mechanisms of progestin?

Answer 3

• Makes cervical mucus thicker and more viscous, impairing sperm penetration
• Atrophy of endometrium leading to impaired implantation
• Uncoordinated contractions impairing sperm and ovum transport

Question 4

Name the 5 common progestins in OCs.

Answer 4

Norethindrone, Levonorgestrel, Desogestrel, Drospirenone, Norgestimate

Question 5

Which progestin has anti-mineralcorticoid activity?

Answer 5

Drospirenone

Question 6

Which 2 progestin have the highest potency?

Answer 6

Levonorgestrel, Desogestrel

Question 7

Which progestin has the most androgenic activity?

Answer 7

Levonorgestrel

Question 8

Which progestin does not have any androgenic activity?

Answer 8

Dropirenone

Question 9

Explain continuous use and give an example of OC that is used this way.

Answer 9

Fixed ratio of estrogen plus progestin for 84 days then low dose estrogen for 7 days. Seasonique

Question 10

How is Seasonique different from Seasonale?

Answer 10

Instead of low dose estrogen for 7 days, you take inactive tablets for 7 days.

Question 11

What are the 3 most serious adverse effects of OC use?

Answer 11

Venous thromboembolism, MI and stroke

Question 12

Which progestin has a higher risk of VTE?

Answer 12

Dropirenone - 10/10,000 person

compared to 6/10,000 in all other OCs

Question 13

T or F. The risk of VTE in pregnancy is higher than in OC users.

Answer 13

True. Risk of VTE in pregnancy = 29/10,000

Question 14

Risk of MI and ischemic stroke is increased by __ fold in healthy, non-smoking women.

Answer 14

Two

Question 15

What are 2 other CV actions of combined estrogen-progestin oral contraceptives?

Answer 15

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

Question 16

What is the mechanism of OC induced BP increase?

Answer 16

Ethinyl estradiol activates Renin-angiotensin system. The effect is offset by decrease in renin production so BP elevation is small.

Question 17

Why does drospirenone not increase BP?

Answer 17

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.

Question 18

What is another effect of drospirenone’s anti-mineralcorticoid activity?

Answer 18

Potential to cause hyperkalemia in high risk patients (i.e. renal or adrenal insufficiency)

Question 19

Effects of OC on blood lipids vary with ____ and _______ of the progestin.

Answer 19

Dose and androgenicity

Question 20

T or F. There is a difference in rates of CHD between androgenic and non-androgenic preparations.

Answer 20

False, incidence of CVD is so low in women that we cannot tell if there is a difference between progestins.

Question 21

Estrogens tend to increase (HDL/LDL) and decrease (HDL/LDL) cholesterol.

Answer 21

Increase HDL and decrease LDL

Question 22

OC can increase the risk of which cancers?

Answer 22

Breast, cervical, and liver

Question 23

OC can decrease the risk of which cancers?

Answer 23

Endometrial and ovarian

Question 24

What are the contraindications to the use of combined OCs?

Answer 24

• 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)

Question 25

What is a major drug interaction of OC?

Answer 25

Drugs that induce hepatic CYP3A4 can increase the breakdown of estrogen. E.g. rifampin, ritonovir, SJW

Question 26

When would a progestin-only pill be used?

Answer 26

Lactation, when estrogen is contraindicated

Question 27

What are some SE of progestin-only pill (Micronor)?

Answer 27

Unpredictable bleeding and spotting, decreased menstrual flow, amenorrhea

Question 28

What does Micronor contain?

Answer 28

0.35mg of norethindrone

Question 29

How does levonorgestrel taken as emergency contraception work?

Answer 29

It interferes with follicular maturation and ovulation by delaying or inhibiting the LH peak.

Question 30

Levonorgestrel is not effective when…

Answer 30

LH surge has begun

Question 31

How is ulipristal different from levonorgestrel as EC?

Answer 31

Ulipristal blocks ovulation even after the LH surge has started by blocking the actions of progesterone.

Question 32

What is the regimen for depot provera?

Answer 32

Inject every 90 days IM

Question 33

Which contraceptive method can cause a longer delay in return to fertility after discontinuation?

Answer 33

Depot provera (medroxyprogesterone acetate suspension)

Question 34

Transdermal patch (Evra) contains which progestin?

Answer 34

Norelgestromin

Question 35

Which contraceptive method causes more breast tenderness and dysmennorhea?

Answer 35

Evra Patch

Question 36

T or F. Nuvaring releases only progestin (etonorgestrel).

Answer 36

False, it also releases ethinyl estradiol.