Contraception

1. Contraception �against� conception methods: prevent sperm from fertilizing ovum prevent implantation most effective> sterilization, the combination pill, IUD, norplant, injectable progestagens next most effective > barrier methods, progesterone-only pill least effective > creams, jellies, natural family planning

2. Female Sterilization: Tubal Ligation performed by laparoscopy under anesthesia oviduct is cut and tied risks: ectopic pregnancies

3. Male Sterilization:Vasectomy performed on an outpatient basis Local anesthesia is administered Vas deferentia are severed and tied off Does not interfere with testosterone production

4. Birth control pills: history most popular reversible form of contraception (approved by FDA in 1960) idea for the pill was first conceived in Europe in late 1890s! doses of E and P in pill have been lowered considerably

5. Combination pill over 30 brands available (all contain synthetic E and P) failure rate is less than 1% hormones mimic luteal phase (preventing ovulation) if pill fails to prevent ovulation, cervical mucus is hostile to sperm transport if fert. occurs, endometrium is unreceptive to embryo

6. Use of the pill available in cycle packages (1 pkg / 28 days) first 21 pills contain E and P last 7 pills are inert > uterine lining shed pregnancy doesn�t occur during last week since it�s not enough time for follicular growth and ovulation

7. Minipill P only; taken daily major effects are: to make cervical mucus hostile to sperm prevent implantation if fert. occurs failure rate is higher than combination pill (0.5 - 10%) usually used when a woman should not take E adverse effects: breakthrough bleeding; risk of ectopic pregnancy

8. Does the pill cause cancer? recent study by U.S. Centers for Disease Control showed no risk of cancer associated with use of pill evidence does suggest that long-term use of comb. pill (8 yrs or more) increases risk (by 2.4 times) of cervical cancer may slightly increase risk of liver cancer

9. Effects of pill on cardiovascular system estrogen increases incidence of blood clotting within blood vessels risk is greatest for those over 35, those with other risk factors (hypertension) or smokers

10. Benefits of combination pill decreased incidence of ovarian and endometrial cancer convenient (but remember: doesn�t prevent STDs) failure rate, cost

11. Norplant approved for use in U.S. in 1991 intradermal implantation of P capsules lasts 5 yrs. mechanism of action is similar to the minipill advantages: convenient, may lower blood cholesterol, low failure rate side effects: uterine bleeding, weight gain, headaches, increased risk of ectopic pregnancy, painful removal

12. Injectable progestogens used in other countries since late 1950s recently approved for use in U.S. injected every 90 days; blocks LH surge failure rate is similar to that of the combination pill side effects are similar to those of Norplant

13. Intrauterine devices small piece of molded plastic inserted into the uterus by physician mechanism of action?? probably prevents implantation: IUD recognized as foreign body in uterus causes inflammation

14. IUDs nylon thread extends into vagina side effects: pain, bleeding risks: perforation of uterus, increased risk of pelvic inflammatory disease failure rate is similar to that of combination pill Dalkon Shield incident has made manufacturers reluctant to market IUDs

15. Natural family planning known as the rhythm method involves restricting intercourse to �safe period� of menstrual cycle only contraceptive method condoned by the Catholic Church without special permission methods for predicting fertile period: calendar method (restricted period based on estimated day of ovulation + sperm and egg survival time); failure rate is 14-47% body temperature method (coitus limited to 3 days after temperature rise thru day 1 of next cycle); failure rate is 1-20% cervical mucus method (coitus is avoided during from start of �wet� days until 4 days later); failure rate is 3-86%

16. �Morning-after� pills an �emergency� form of contraception that reduces risk of pregnancy involves intense dose of birth control pills taken with 72 hrs. of intercourse, followed by a 2nd dose 24 hrs. later mechanism of action: prevents LH surge if it hasn�t already occurred prevents implantation must be prescribed by physician

17. MAP, cont�d. short term side effects: nausea and vomiting breast pain delay in next menstrual period not recommended for women with history or cardiovascular disease during fertile phase of cycle, reduces risk of pregnancy from 30% to 8% not considered a form of abortion

18. Future contraceptive methods many drug companies aren�t interested in supporting development efforts since: they feel market is well-served worries about product liability money and studies required for approval

19. Possibilities currently under investigation anti-zona pellucida antibody injection in females: blocks zona pellucida protein that binds to sperm animal testing ongoing anti-FSH antibody injection in males: halts spermatogenesis without disrupting testosterone production clinical trials ongoing in U.S.; used in India

20. Possibilities, cont�d. GnRH antagonist plus testosterone treatment in males (daily pill): blocks spermatogenesis but maintains androgen levels clinical trials ongoing androgen treatments in males (weekly injections, implants, pills, patch): blocks spermatogenesis while maintaining androgen levels acts to enhance negative feedback of testosterone on pituitary, brain drugs currently under study are less harmful than the anabolic steroids clinical trials are ongoing