Unit 9 CONTRACEPTION LEARNING OBJECTIVES

Transcription

1 Unit 9 CONTRACEPTION LEARNING OBJECTIVES 1. Become aware of the magnitude of teen age sexual activity and pregnancy and some of the social and economic effects. 2. Learn about the various means of contraception, their efficiency, and dangers. 3. Learn how the various means of contraception prevent the production of children. 4. Learn some of the reasons that the most rapidly growing (developing) nations do not use contraceptives to the extent they are used in developed countries. Introduction Most animals are limited in the number of offspring they reproduce that in turn live to reproductive age. Various factors including predators, food availability, and disease limit their reproductive capacity. For most of human history, human reproduction was also limited or controlled by these same factors. Now, at least in developed nations, these factors have been largely eliminated. Also the need for large families to assure a work force and guarantee care of the elderly has changed as the majority of people moved from farm to city and various social systems have been established for the care of the elderly. Now many individuals wish to restrict their family size. In the past sexually activity often resulted in offspring. The fact that there is still a problem in unwanted pregnancies is illustrated in Figure 9-1 taken from The ZPG Reporter, Jan/Feb, It shows that the United States has a much higher rate of pregnancies and abortions in the year age group than many other industrial nations. These statistics are not unexpected when the increase in percent of teens having sex by age 18 is observed (Fig. 9-2). Adverse results of teen pregnancy include: 1) 70% of teen mothers drop out of high school; 2) teen mothers have more children; and 3) teen mothers depend more on public 108

2 Figure 9-1. Percent of unintended pregnancies (excluding miscarriages) to teens years which end in abortion and live births. assistance than teens who don t have children. More recently health professionals have become concerned with the prevalence of oral sex in teens. Figures 9-3, 9-4, 9-5, and 9-6 show the result of questioners give in 2002, and show the comparisons between males and females or different ages and virgins and sexually experienced. Just over half of teens aged 15-19, 54% girls and 55% boys, say they have had oral sex (fig. 9-3). Figure 9-4 shows that experience with oral sex increases with age; less than 45% of the year teens reported having oral sex as compared to over 70% of the aged Figures 9-5 and 9-6 show that sexually experienced males and females are more likely the have participated in oral sex than non-experienced. Figured 9-7 and 9-8 indicate the reasons for having had oral sex given by virgin boys and virgin girls respectively. A little more that 35% indicated it is a method of avoiding STDs. A study by the Kaiser Family Foundation found that 26% of sexually active year olds believed that one can not get HIV from oral sex and another 15% didn t know if HIV could be contacted by oral sex. Scientist have documented that Herpes, Syphilis, Gonorrhea, Chlamydia, Genital warts, and HIV can be transmitted through oral sex, even though the incidence is lower than with vaginal sex. American society has been historically averse to dealing with issues about reproductive health and sexuality as compared to other countries. In recent years, methods have been developed, which permit frequent sexually activity without the risk of offspring. In this unit we will discuss some of the methods, their efficiency, and risks. 109

3 Figure 9-2. Percent of teens having sex by age 18. Taken from ZPG Reporter, Jan/Feb Figure 9-3. Percent of teens (aged 15-19) who report having received or performed oral sex. From Science Says: Teens and Oral Sex Number 17, Sept. 2005, 110

4 Figure 9-4. Difference by age in the percent of teens who report having given or received oral sex. From Science Says: Teens and Oral Sex Number 17, Sept. 2005, Figure 9-5. Percent of virgin and sexually experienced teens who have received or performed oral sex, by gender. From Science Says: Teens and Oral Sex Number 17, Sept. 2005, 111

5 Figure 9-6. Percent of virgin and sexually experienced teens who have had oral sex (given or received), by age. From Science Says: Teens and Oral Sex Number 17, Sept. 2005, Figure 9-7. Proportion of virgin boys who have had oral sex, by main reason for postponing sexual intercourse. From Science Says: Teens and Oral Sex Number 17, Sept. 2005, 112

6 Figure 9-8. Portion of virgin girls who have had oral sex, by main reason for postponing sexual intercourse. From Science Says: Teens and Oral Sex Number 17, Sept. 2005, Contraception means against taking in this case the taking of a child. Prevention of pregnancy can be placed in three categories: 1) prevention of egg and sperm meeting in the female reproductive tract (fertilization is prevented); 2) prevention of implantation of the zygote, actually the embryo; and 3) preventing the release of mature eggs or sperm from the gonad. Table 9-1 lists the various methods, their effectiveness, and their risks. Table 9-1. Common birth-control methods. Name Effectiveness Method Risk Prevention of sperm and egg meeting Abstinence 100% Refrain from sex None Rhythm method 70% Abstinence 5-8 days None around time of ovulation Coitus interruptus 75% Withdraw penis prior to ejaculation None if ignore emotional stress Male condom 85% Fits over penis; traps None sperm; prevents STDs Female condom 85% Inserted with applicator; None outer rings holds condom in place; blocks sperm; prevents STDs Diaphragm (with 90% Inserted in vagina, covers None jelly) cervix; must be fitted Cervical cap 85% Latex cup held by suction over cervix; disposable; delivers spermicide Cervical cancer? 113

7 Jelly, creams, and foams 75% Inserted before intercourse; kills sperm Vaginal sponge 75% Small piece of foam is impregnated with spermicide jelly; place over cervix; effective immediately & for up to 24 hours Douch 70% Clean vagina after intercourse Prevention of implantation IUD, Intrauterine 90+% Plastic coil inserted into Device uterus by MD; some have progesterone in stem RU486 95% Requires taking two pills about 3 days apart; prescription Morning after pill 85% Take synthetic progesterone 72 hrs and 84 hrs after unprotected sex None None None Can cause PID Can cause excess bleeding Prevention of release of egg or sperm from gonad or from reproductive system Birth control pill Almost 100% Synthetic estrogen and progesterone stops FSH and LH Blood clots in smokers Norplant 90+% Insert progesterone releasing device under the skin; good for up to 5 years Depo-Provera 99% 4 injections of synthetic progesterone per year Gossypol?? Pill for men; disables testicular cells; not available in the U.S.???? none Breast cancer? Sterility in some Vasectomy 100% Cut and tie vas deferens Difficult to reverse Tubal ligation 100% Cut and tie oviducts Difficult to reverse Some new methods or modifications of older methods include: 1) Lea s Contraceptive is a modified diaphragm-like device in one size. It is available as an over-the-counter product in Germany, and was approved by the U.S. FDA in March It should remain in place at least 8 hours after intercourse, but be worn no longer than 48 hours before removing to wash. Pregnancy rates were 15% as compared with percent for standard diaphragm with spermicide. 2) Fem Cap is a modified cervical cap with a strap to aid in removal. It is available in some European countries and was approved for use in the U.S. in March, Found to be somewhat less effective than the standard cap, about 23% pregnancy. 3) Jadelle is a system of two Silastic rods that release levonorgestrel; it is undergoing registration in Europe. Duration of action is 5 years. 4) Implanon is a single implant system that releases etonogestrel; it is 114

8 registered is some foreign countries. Duration of action is 3 years. 5) Contraceptive Patch is a small patch containing estrogen and progesterone similar to the Pill but contains enough of the hormones so that the blood level of users contains 60 % more of the hormones. A new patch is put on every week for three weeks and then no patch for the fourth week. It has not been in use long enough to know all the risks, but there are certain risks and one should only use the patch with a doctor s advise. Usually upon seeing a doctor, you are given 3 months supply to see how It suits you and then you should check with your doctor. 6) Copper-T intrauterine device (IUD) which can be used up to 5 days after unprotected intercourse to prevent pregnancy. More effective than Emergency Contraceptive Pills; it reduces the rate of pregnancy by 90%. Can be left in place for 3-10 years depending upon the type and countryspecific licensing. 7) Pill for men is in clinical trials. The pill uses synthetic hormones to lower the sperm count. The effect is temporary. 8) Reversible inhibition of sperm under guidance, RISUG, works by an Injection into the vas deference. The injection coats the walls of the vas deferens with a clear gel made of 60 mg of the copolymere styrene/ dnhydride with 120 ul of the solvent dimethyl sulfoxide. Within an hour, the drugs produce an electrical charge that nullifies the electrical charge of the sperm preventing them from penetrating the egg. The effect can be reversed by washing the vas deferens. Some see the use of RISUG as having the disadvantage of no longer necessitating the use of the male condom, which offers protection against some STDs. 9) Vaccinations for males are in the investigation stage. This immunocontraceptive works by preventing or slowing sperm production by an immune system response to the hormone FSH, which is vital to the maturation of sperm. Men regain their fertility as the effect wears off. However, in clinical trials the vaccine was shown to work on only 1/3 of the men. Figure 9-9 illustrates some of the contraceptive methods. With all these methods available, what types are used by the people in the United States? Table 9-2 shows the types being used and the percent use of each. The 1995 Family Growth Survey reports that female sterilization is still the most widely used method in U.S. at 27.37%. The pill runs a close second at 26.9%. These methods, with the exception of Gossypol, are all available to prevent pregnancy in U.S. women. Developing countries, where most population increase is occurring, do not have these methods available. In some cases religious and cultural beliefs prohibit the use of contraceptives, but it is the unavailability and ignorance of their use that prevents many women in these countries from using them. Family planning is being introduced in some of these nations, but to facilitate the desire to reduce family size, safer, more convenient methods are being developed. Research is being done on nasal spray contraceptives, transdermal patches (technique similar to smokers patch), biodegradable implants which work for 18 months and do not have to be removed. The Food and Drug Association has approved the morning-after pill for over the counter sales, but the female must show proof of being 18 years or older Taken within three days of sexual intercourse, the prescription pill prevents ovulation or, if that already has occurred, blocks implantation of a fertilized egg in the uterus. AMA suggests that 115

9 under the present conditions, a woman might not be able to get the pill in time to prevent a pregnancy. The morning-after pill is essentially a high-dose birth control pill. It is different from the RU486 abortion pill which acts by causing contractions to expel an embryo from the uterus; RU486 can be given up to seven weeks after the start of the last menstrual period. Figure 9-9. Showing various contraceptive methods including vasectomy (A), tubal ligation (B), diaphragm (C), IUD (D), cervical cap (E),and female condom (F). 116

10 Table 9-2. Contraceptives by percent use in the United States 1 Type Percent Female sterilization 27.6% Pill 26.9% Male condom 20.4% Male sterilization 10.9% Withdrawal 3.1% Injectable 3.0% Periodic abstinence 2.3% Diaphragm 1.9% Implant 1.4% IUD 0.8% Female condom 0.0% Other methods 1.6% 1 As this survey was taken in 1995, a more recent survey would show some differences due to the availability of morning after pill and RU486. A more recent survey taken in 2002 shows the following: Type Percent Pill 30.6% Female sterilization 27.0% Male condom 18.0% Male sterilization 9.2% 3 Month injections 5.3% Other mechanisms 9.9% 117

11 Unit 9 OBJECTIVE QUESTIONS OVER CONTRACEPTION 1. Which of the following methods employs prevention of implantation as a method of contraception? (A) Birth control pill (B) Depo-Provera C) RU486 (D) Diaphragm. 2. Which of the following methods has the lowest percent success? (A) Vasectomy (B) Birth control pill (C) Male condom (D) Tubal ligation. 3. Which of the following methods is best for preventing transmission of STDs? (A) Vasectomy (B) Diaphragm (C) Douche (D) Male condom (E) IUD 4. Which of the following methods has no known risk factors? (A) IUD (B) Male condom (C) Birth control pill (D) Cervical cap 5. If one is employing the rhythm method of birth control, he/she should refrain from unprotected sex for a period of (A) 2-4 days (B) 5-8 days (C) 7-14 days (D) days around the time of ovulation. 6. Which of following methods has not been approved for use in the U.S.? (A) RU486 (B) Gossypol (C) IUD (D) Norplant 7. The commonest form of contraception in the U.S. is (A) tubal ligation (B) Birth control pill (C) vasectomy (D) male condom. 8. It is necessary to enter the abdominal cavity to perform (A) tubal ligation (B) vasectomy (C) both A and B (D) neither A or B. 9. A doctor s assistance is required or suggested in all but one of these methods. Which one is not? (A) vasectomy (B) tubal ligation (C) implants (D) diaphragm (E) female condom. 10. Which of the following has the lowest percent of success? (A) Jellies, creams, and foams (B) Contraceptive sponge (C) Douche (D) Cervical cap. DISCUSSION QUESTIONS OVER CONTRACEPTION 1. What are some of the difficulties of using the rhythm method or family planning? 118

12 2. Which methods of contraception are also good methods for STD prevention? 3. List the methods of contraception that have the best chances of being successful. 4. Which methods could be considered as abortion methods? Explain. 5. Most texts suggest that the birth-control pill is taken daily? Is that correct? Explain. 6. Some men after having a vasectomy relate that they are no longer able to have an ejaculation. Explain the reason for this. 7. What happens to the released sperm or eggs in the case of a man with a vasectomy or a woman with tubal ligation? 8. Suggest reasons that a woman doesn t want a tubal ligation or a man a vasectomy. 9. What are some of the problems involved in the use of contraceptive methods in third world countries? 119