Contraceptives Flashcards
Goals of Contraception
- Most common goal = prevention of pregnancy
- Other goals:
- Menstrual cycle regulation
- Reduction of premenstrual symptoms
- Treatment of acne
which oral contraceptives have less side effects
Progesting-only oral contraceptives
- Norethindrone, Norgestrel
Combined oral contraceptives
- Contain a combination of an estrogen and a progestin
- The estrogen is either ethinyl estradiol or mestranol
- Mestranol is a prodrug that is converted to ethinyl estradiol
• Progestins include:
- Norethindrone
- Norgestrel
- Levonorgestrel
- Desogestrel
- Norgestimate
- Drospirenone
• Progestins vary in their androgenic activity (highest to lowest):
• Levonorgestrel and norgestrel: highest • Norethindrone: lower • Third-generation progestins, such as desogestrel and norgestimate: even lower • Drospirenone: antiandrogenic
Combination contraceptives MOA
• Combination oral contraceptives work primarily before
fertilization to prevent conception
• They act by preventing ovulation
• They suppress LH and FSH release and ovulation does
not occur
• Additionally, the progestin thickens cervical mucus thus
preventing sperm penetration, and induces changes in the
endometrium that impair implantation
Benefits of combined oral contraceptives
• Reduction on the risk of endometrial cancer
• Reduction in the risk of ovarian cancer
• Improved regulation of menstruation
• Relief of benign breast disease
• Prevention of ovarian cysts
• Reduction in the risk of symptomatic pelvic inflammatory
disease
• Improvement in acne control
combined oral contraceptives AE
• Concerns about cardiovascular toxicity initially limited the long-term use of these drugs
• The decrease in estrogen and progestin content has led
to a reduction in adverse effects
• Concerns about cardiovascular toxicity initially limited the long-term use of these drugs
Insulin Resistance
• Progestins may cause insulin resistance by competing
with insulin for its receptor
- Hirsutism (androgenic progestins)
- Melasma (melanocyte stimulation by estrogen)
Cardiovascular Disorders
• Estrogens increase production of factor VII, factor X and
fibrinogen, therefore increasing the risk of thromboembolic events
• The risk is increase by obesity, smoking, hypertension and diabetes
combined oral contraceptives
DI:
Liver Enzyme Induction
• Rifampin induces hepatic P450 enzymes and increases
metabolism of estrogen
• Use of a backup nonhormonal contraceptive method
during the course of rifampin therapy is recommended
Types of combined oral contraceptives:
• Continuous combination regimens
- how do they work
provide hormone containing pills for 21 days, then very-low-dose estrogen and progestin for an additional 4-7 days
Types of combined oral contraceptives:
• Extended-cycle formulations
- how do they work
• Extended-cycle formulations increase the number of
hormone-containing pills to 84 days, followed by a 7-day
placebo phase
• This results in four menstrual cycles per year
- good for painful mensturatioon
Types of combined oral contraceptives:
• Most of the formulations available have 21 hormonally
active pills
21 hormonally
active pills followed by 7 placebo pills to allow withdrawal
from bleeding
• This facilitates consistent daily pill intake
•Most common adverse effect of oral contraceptives?
Cause?
Breakthrough Bleeding
• It is more of a problem with lower doses of estrogen
because estrogen stabilizes the endometrium
AE Oral contraceptives: Cardiovascular Disorders - how often does this happen? - what other AE accompany this? - common in which age group?
• Although rare, the most serious adverse effect of oral
contraceptives is cardiovascular disease
• This includes thromboembolism, thrombophlebitis,
hypertension, MI, cerebral and coronary thrombosis
• These adverse effects are most common among women
who smoke and who are older than 35 years
Oral contraceptives decrease or increase carcinogenicity (ENDOMETRIAL OR OVARIAN CANCER)?
DECREASE!
• Carbamazepine, oxcarbazepine, phenytoin,
phenobarbital, primidone, topiramate, vigabatrin and
St John’s Wort are:
P450 inducers and should not be given together with OCs
How can antibacterials interrupt Ethinyl estradiol estrogenic effects?
• Ethinyl estradiol is conjugated in the liver, excreted in the
bile, hydrolyzed by intestinal bacteria, and reabsorbed as
active drug
• Certain broad-spectrum antibiotics, by reducing the
population of intestinal bacteria, may interrupt the
enterohepatic circulation of estrogen
• This may decrease estrogen levels
CI: ABSOLUTE
- Pregnancy
- Thrombophlebitis or thromboembolic disorders
- Stroke or coronary artery disease
- Cancer of the breast
- Undiagnosed abnormal vaginal bleeding
- Estrogen-dependent cancer
- Benign or malignant tumor of the liver
- Uncontrolled hypertension
- Diabetes mellitus with vascular disease
- Age over 35 and smoking >15 cigarettes daily
- Thrombophilia
- Migraine with aura
- Active hepatitis
- Surgery or orthopedic injury with prolonged immobilization
CI: RELATIVE
- Migraine without aura
- Hypertension
- Heart of kidney disease
- Diabetes mellitus
- Gallbladder disease
- Cholestasis during pregnancy
- Sickle cell disease (S/S or S/C type)
- Lactation
Progestin-Only Pills
have no risk of?
Other benefits?
- Not widely used in the US
- Contain norethindrone or norgestrel
• Slightly less effective than combined oral contraceptives
• No risk of thromboembolic events-dont stimulate clotting factors
• Other benefits: decreased dysmenorrhea, decreased
menstrual blood loss and decreased premenstrual
syndrome symptoms
• Unscheduled bleeding and spotting are common
Non-Oral hormonal Contraceptives
• The Patch: Transdermal patch that contains both ethinyl estradiol
and a progestin
• The Ring: Transvaginal delivery system that delivers ethinyl
estradiol and a progestin
• The Progestin Injection:
• The Progestin Implant
• The Intrauterine Systems
Progestin Injection:
has BB warning against risk of potentialy irreversible BMD loss associated w/ long term use.
Depo-Provera®
• Progestin-only injectable contraceptive
• Contains depot medroxyprogesterone acetate (DMPA)
• Given IM every 3 months
• Extremely effective
- inhibits ovulation through negative feedback
Progestin Implants
• Single 4 cm long implant, containing a progestin
• Placed under the skin of the upper arm using a preloaded
inserter
• Effective for 3 years
•Major adverse effect: irregular menstrual bleeding
Intrauterine Systems
- Levonorgestrel-releasing intrauterine system
- It has a polyethylene body with a levonorgestrel reservoir
- Effective for 5 years
Emergency Postcoital Contraception:
Plan B and Next Choice!
Plan B® and Next Choice®
• Both Plan B® and Next Choiceo a a d e C o ce® contain two tablets of
levonorgestrel
• The first tablet is taken within 72 hours of unprotected
intercourse and the second 12 hours later
• Adverse effects include nausea and vomiting
• Available without a prescription for consumers ≥17
Plan B One-Step®
• Plan B One-Step® contains one a O e S ep co a s o e tablet of levonorgestrel
to be taken within 72 hours after unprotected intercourse
• Available without a prescription for consumers ≥17
Ella®
• Ella® contains ulipristal acetate
• Ulipristel acetate is a selective progesterone receptor
modulator (SPRM)
• It acts as a progesterone antagonist to inhibit or delay
ovulation
• A single tablet is taken within 5 days after intercourse
• Adverse effects are similar to those of levonorgestrel
• Available only by prescription
within how many days should copper IUD be inserted after intercourse?
5 days
