Transcript Contraceptionx

Contraception
Birth Control
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Interfering with the reproductive process at
any step from gametogenesis to nidation
(implantation of a fertilized ovum)
Safety
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Difficult to assess
A large quantity of our data was gathered
when birth control was used in higher doses
than are used today
Effectiveness vs. safety
Selecting a Birth Control Method
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Consider:
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Effectiveness
Safety
Personal preference
Oral Contraceptives
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Mechanism: inhibit ovulation
Classification (two main categories)
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Combination oral contraceptives (OCs)
• Estrogen and progestin
Progestin-only OCs
Three major subgroups of combination OCs
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Monophasic
Biphasic
Triphasic
Combination Oral Contraceptives
(OCs): Adverse Effects
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Thromboembolic disorders
Hypertension
Cancer
Teratogenic effects
Abnormal uterine bleeding
Use in pregnancy and lactation
Benign hepatic adenoma
Glucose intolerance
Other adverse effects
Noncontraceptive Benefits of OCs
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Decrease risks of ovarian cancer,
endometrial cancer, ovarian cysts, pelvic
inflammatory disease, benign breast disease,
iron deficiency, anemia, and acne
Favorable effect on menstrual cycles
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Reduced cramps; lighter, shorter, more
predictable flow
Combination Oral
Contraceptives—Drug Interactions
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Drugs and herbs that reduce the effects of
OCs
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Rifampin
Ritonavir
Antiepileptic drugs
St. John’s wort
Combination Oral
Contraceptives: Drug Interactions
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Drugs whose effects are reduced by OCs
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Drugs whose effects are increased by OCs
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Warfarin
Insulin
Oral hypoglycemics
Several agents, including theophylline, tricyclic
antidepressants, diazepam, and chlordiazepoxide
Drugs that elevate potassium should be
avoided by patients on yasmin (Yaz)
Combination Contraceptives with
Novel Delivery Systems
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Transdermal contraceptive patch
Vaginal contraceptive ring
Long-Acting Contraceptives
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Subdermal etonorgestrel implants
Depot medroxyprogesterone acetate (MPA)
Intrauterine devices
Spermicides
Barrier devices
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Condoms: male and female
Diaphragm
Cervical cap
Drugs for Medical Abortion
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Mifepristone (RU 486) with misoprostol
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Blocks uterine progesterone receptors
Adverse effects
• Bleeding
• Cramping
• Nausea
• Vomiting
• Diarrhea
• Headache
Drugs for Medical Abortion
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Methotrexate with misoprostol
Prostaglandins: misoprostol, carboprost,
dinoprostone
Emergency Contraception
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Contraception implemented after intercourse
Following rape, failed contraception, or failure
to use contraception
Plan B
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2 high-dose tablets of levonorgestrel (progestin)
1 tablet within 72 hours and another 12 hours later
Alternatives to Plan B