Definition • Contraception (birth control) prevents pregnancy by interfering with the normal process of ovulation, fertilization, and implantation. There are different kinds of birth control that act at different points in the process. Purpose • Every month, a woman's body begins the process that can potentially lead to pregnancy. An egg (ovum) matures, the mucus that is secreted by the cervix (a cylindrical-shaped organ at the lower end of the uterus) changes to be more inviting to sperm, and the lining of the uterus grows in preparation for receiving a fertilized egg. Any woman who wants to prevent pregnancy must use a reliable form of birth control. • Birth control (contraception) is designed to interfere with the normal process and prevent the pregnancy that could result. There are different kinds of birth control that act at different points in the process, from ovulation, through fertilization, to implantation. Each method has its own side effects and risks. Some methods are more reliable than others. History of birth control techniques • Ancient Egypt and Rome • about 1850 BC. It describes various contraceptive pessaries, including acacia gum, which recent research has confirmed to have spermatocidal qualities and is still used in contraceptive jellies. Other birth control methods mentioned in the papyrus include the application of gummy substances to cover the "mouth of the womb", a mixture of honey and sodium carbonate applied to the inside of the vagina History of birth control techniques • Ancient China • In the same century Sun Ssu-mo documented the "thousand of gold contraceptive prescription" for women who no longer want to bear children. Made of oil and quicksilver heated together for one day and taken orally the prescription induced sterility History of birth control techniques • Early Islam • In the late ninth to early tenth century the Persian physician Muhammad ibn Zakariya al-Razi documents coitus interruptus, preventing ejaculation and the use of suppositories to block the cervix as birth control methods. He describes a number of suppositories, including elephant dung, cabbages and pitch, used alone or in combination. During the same period Ali ibn Abbas al-Majusi documents the use of suppositories made of rock salt for women for whom pregnancy may be dangerous. In the early tenth century Abu Ali al-Hussain ibn Abdallah ibn Sina, known in Europe as Avicenna, included a chapter on birth control in his medical encyclopaedia The Canon of Medicine, documenting 20 different methods . Methods • There are more different types of birth control available today than ever. They can be divided into a few groups based on how they work. These groups include: • 1- Physical methods • 2-Behavioral methods Methods • Physical methods • Hormonal methods – Barrier methods – Ormeloxifene (Centchroman) – Emergency contraception – Intrauterine methods – Sterilization Physical methods Hormonal methods • Female hormonal contraception • There are various delivery methods for hormonal contraception. Forms of synthetic oestrogens and progestins (synthetic progestogens) combinations commonly used include the combined oral contraceptive pill ("The Pill"), the Patch, and the contraceptive vaginal ring ("NuvaRing"). A monthly injectable form. Physical methods Hormonal methods • Other methods contain only a progestin (a synthetic progestogen). These include the progesterone-only pill (the POP or 'minipill'), the injectables Depo Provera (a depot formulation of medroxyprogesterone acetate given as an intramuscular injection every three months) and Noristerat (Norethindrone acetate given as an intramuscular injection every 8 weeks), and contraceptive implants. The progestin-only pill must be taken at more precisely remembered times each day than combined pills. How Hormonal Methods Work • Hormonal contraceptives prevent ovulation. No egg is released so sperm cannot fertilize it. It is widely agreed that this is a major mechanism of hormonal birth control. • A woman may ovulate anyway. Hormonal contraceptives may also prevent fertilization by changing the consistency of natural secretions in the vagina, making it harder for the sperm to reach the egg. It is not clear how effective this mechanism is in preventing fertilization How Hormonal Methods Work A woman may ovulate anyway, and sperm may • still reach the egg, resulting in fertilization. When this occurs, hormonal contraceptives make it in the uterus by implant difficult for the embryo to keeping the edometrium (lining of the uterus) thinned. This results in the death and expulsion of the embryo. Most scientists agree this occurs, Some doctors do .but it is not clear how often because not prescribe hormonal contraceptives .they find this mechanism objectionable Physical methods Hormonal methods Mechanism of Action and Efficacy • 1-PILLS: • Progestin-only pills contain one of the synthetic • progestins (levonorgestrel, norethindrone, norgestrel, lynestrenol, desogestrel, or ethynodiol diacetate) in small amounts to prevent conception through a combination of mechanisms: ovulation suppression in some cycles, thickening of cervical mucus to prevent sperm penetration, atrophy of the endometrium (shrinking of the lining of the uterus), and altered tubal function. The amount of progestin in progestin-only pills is about 25% of that in combined (estrogen and progestin) oral contraceptive pills. Physical methods Hormonal methods Progestin-only pills must be taken at the same • time each day to be effective. The hormone is eliminated within 24 hours, at which time the cervical mucus regains its normal permeability to sperm. As a result, progestin-only pills typically have higher failure rates than combined oral contraceptives. With perfect use, the first-year probability of pregnancy is 0.5%. With typical use, the failure rate is 8%, varying according to age How take??? Most combination pills come in either a 21-day • pack or a 28-day pack. One hormone pill is taken each day at about the same time for 21 days. Depending on your pack, you will either stop taking birth control pills for 7 days (as in the 21-day pack) or you will take a pill that contains no hormones for 7 days (the 28-day pack). A woman has her period when she stops taking the pills that contain hormones. Some women prefer the 28-day pack because it helps them .stay in the habit of taking a pill every day Physical methods Hormonal methods Physical methods Hormonal methods 2- Depot • Depot medroxyprogesterone acetate is given as • a 1 milliliter (150 mg of microcrystals), deep intramuscular injection every 12 weeks. Because DMPA is not a sustained-release system, its action relies on obtaining high levels of progestin which decline over three months, but can remain above a contraceptive concentration for n the first year of use in the United States is 0.3% with Physical methods Hormonal methods perfect use and three percent in the first • year with typical use because some women do not return for their injections from a nurse or physician every three months as required for maximum efficacy many additional weeks. Physical methods Hormonal methods 3- A contraceptive implant • Physical methods Hormonal methods containing 68 mg of the progestin etonogestrel • in a single rod made of ethylene vinyl acetate (EVA) was approved for use in the United States in July, 2006, is initially absorbed by the body at a rate of 60 micrograms (mcg) per day which slowly declines to 30 mcg per day after two years of use. The ENG implant can be removed at any time at the woman’s discretion, but will remain effective for at least three years compared to the seven years efficacy of Norplant Physical methods Hormonal methods Progestin-containing implants have two primary • mechanisms of action: inhibition of ovulation and restriction of sperm penetration through cervical mucus implant (Implanon) suppresses ovulation by controlling hormones in the pituitary and hypothalamus glands which is required to support the production, growth, and maturation of eggs in the ovary. Progestins affect the cervical mucus, making it viscous and scanty so that sperm cannot enter the uterus and reach the egg to fertilize it . No signs of embryonic development have been found • among implant users. How is the contraceptive implant put under the skin • .It is put in the inner side of the upper arm • It is usually first inserted within five days of a • period starting. (This ensures that you are not .pregnant.) It is effective from then on An injection of local anaesthetic is used to numb • the skin. A small cut is made and the implant placed under the skin. The wound is dressed .and will soon heal just like any other small cut The area around the implant may be bruised • .and sore for a few days, but this soon goes Physical methods Hormonal methods Physical methods Hormonal methods • Combined Contraceptive Vaginal Ring • vaginal ring is a flexible, transparent ring 54 mm in diameter, made of ethylene vinyl acetate (EVA) copolymer plastic. The user places and removes the ring herself; there is no “wrong” way to insert it as long as it touches the vaginal lining. Each ring is designed for one cycle of use, Physical methods Hormonal methods , which is three weeks of continuous ring • use followed by one week without the ring to provoke a scheduled withdrawal bleed. The ring releases 120 mcg of etonogestrel (the active metabolite of desogestrel) and 15 mcg of ethinyl estradiol per day. Physical methods Hormonal methods Physical methods Hormonal methods • Transdermal Contraceptive System (THE PATCH Physical methods Hormonal methods The transdermal contraceptive system is a 4.5- • cm square patch that provides continuous circulatory levels of norelgestromin (the active metabolite of norgestimate) and ethinyl estradiol equivalent to 150 mcg of norelgestromin and 20 mcg of ethinyl estradiol per day. It is usually placed on the hip or abdomen and should not be applied to the breasts. The total amount (measured by AUC) of the hormonal concentrations achieved by the patch is greater than with typical OCs Physical methods Hormonal methods . One patch is applied weekly for three • consecutive weeks, followed by one week without its use to allow for a scheduled withdrawal bleed The first-year pregnancy rate for perfect • use is 0.3% Patches maintain adhesiveness for a week • regardless of heat, moisture, activity levels Physical methods Hormonal methods Benefits • The non-contraceptive benefits of progestin- • only methods include decreases in menstrual blood loss, anemia, menstrual cramping, ovulatory pain, and pain with endometriosis (abnormal growth of the tissue that lines the uterus), as well as decreased risks of endometrial and ovarian cancer. Progestin-only methods may be safely used while breastfeeding. Physical methods Hormonal methods Disadvantages and Side Effects • Hormonal methods do not protect against • sexually transmitted diseases (STDs) and human immunodeficiency virus (HIV), although they may provide some protection against pelvic inflammatory disease (PID) by thickening cervical mucus, which is also an important factor in their contraceptive action Physical methods Hormonal methods Menstrual disturbances are the main reason • why women discontinue progestin-only contraception, but women may also experience systemic side effects, such as breast tenderness, acne, and mood changes, including depression. Some of the less common systemic side effects of implants and injections, such as acne and unwanted hair growth or loss, are associated with the decrease in levels of sex hormone-binding globulin caused by decreased ovarian production of estradiol Physical methods Hormonal methods Weight gain is a common reason for • discontinuing hormonal contraceptives, but only the injectable DMPA (DepoProvera) has been clearly associated with increasing weight, and then only in young women who were already overweight when they initiated use. Physical methods Hormonal methods current breast cancer. Use of a progestin-only • method is generally NOT recommended for women who have had breast cancer treated without recurrence for less than five years, active hepatitis, severe cirrhosis, benign or malignant liver tumors, current deep vein thrombosis (blood clots), or pulmonary embolism (blood clot in the lung). Discontinuing progestin-only methods should be considered by who anyone who develops migraines with focal neurologic symptoms, ischemic heart disease, or stroke . S.E hair growth acne Male hormonal cotraceptive Commonly known as the “male pill” • contained Testosterone , a hormonal contraceptive for men will probably not be delivered as a pill. Researchers are coming closer to a marketable male hormonal contraceptive (MHC) delivered by injection or implant, but there is nothing commercially .available right now Male hormonal cotraceptive ?How would it work • Male hormonal contraceptives attempt to block • or severely reduce the production of sperm. They accomplish this by stopping the secretion of a man's reproductive hormones in the brain and testes. When levels of testosterone in the testes are low, sperm production slows or halts. Typical MHC formulations provide replacement testosterone to the man’s bloodstream to maintain male characteristics like muscle mass and facial hair. Male hormonal cotraceptive ?How long would it take • The fastest possible onset of efficacy that • a man taking an MHC could hope for would be 1½ - 2½ months. Once spermatogenesis is halted, it takes an average of 2½ months for the last spermatids produced to travel through and exit the epididymis. Male hormonal cotraceptive ?What side effects would be expected • weight gain, increased acne and changes in mood. • .These side effects are. A more serious side effect of altering a man's androgen • metabolism is a depressed level of high-density lipoprotein cholesterol (HDL-C) in the blood. HDL-C is a healthy type of cholesterol which has been correlated with reduced risk of atherosclerosis (hardening of the arteries). Volunteers in clinical trials of certain types of synthetic androgen experience a 15% drop in HDL-C levels. If this side effect can not be mitigated, men with a risk of heart disease should be advised to avoid MHCs Researchers were originally concerned that high levels • of androgen might over-stimulate the prostate gland Physical methods Intrauterine methods Physical methods Intrauterine methods An intrauterine device. • These are contraceptive devices that are • placed inside the uterus. They are usually shaped like a "T" — the arms of the T help hold the device in place. There are also frameless IUDs, which are less likely to cause complications; an example would be GyneFix. This brand is hard to find in North America. There are two main types of intrauterine contraceptives: Physical methods Intrauterine methods 1-those that contain copper (which has a spermicidal • effect), The copper device is approved for 10 years of use • but has been shown to be effective for at least 12 years. After prolonged continuous use, the cumulative pregnancy rate is 1.6 percent at seven years, and 2.2 percent at 8 and 12 years. Overall, the failure rate is substantially less than one per 100 women per year, except in women under age 25 who experience a slightly higher failure rate, most likely because they are more fertile than older women Physical methods Intrauterine methods Mechanism of Action and Efficacy • he copper IUD releases free copper and • copper salts that have both a biochemical and morphologic impact on the uterine lining (endometrium) and produce alterations in cervical mucus and secretions which also have spermicidal effects. Physical methods Intrauterine methods Advantages and Noncontraceptive Benefits • Women who cannot use hormonal methods can • use copper IUCs. There is rapid return to fertility and no increased risk of infertility after IUC removalThe copper device is associated with a decreased risk of endometrial cancer, and no increased risk, and possibly a decreased risk, of cervical cancer Physical methods Intrauterine methods Disadvantages and Side Effects • The copper IUC may increase menstrual • blood loss, cramping, intermenstrual spotting, and vaginal discharge. Heavy menses and dysmenorrhea Physical methods Intrauterine methods 2- and those that release a progestin (a synthetic • progestogen). The levonorgestrel system is approved for up to five • years of use in the United States but has been shown to be effective up to seven years Mechanism of Action and Efficacy • the progestin released by hormonal IUCs shrinks the • glandula structures in the uterine lining and thickens cervical mucus so that sperm cannot penetrate it (1, 48). The levonorgestrel system also produces serum concentrations of progestin that lead to partial inhibition of ovarian egg development and ovulation. Physical methods Intrauterine methods Advantages and Noncontraceptive Benefits • more effective than oral progestins • In women who sometimes fail to ovulate and • in perimenopausal and postmenopausal women taking estrogen, the levonorgestrel IUC can be used to protect the uterine lining from the effects of estrogen by preventing the overgrowth that can lead to cancer of the uterus Physical methods Intrauterine methods Disadvantages and Side Effects • may cause irregular bleeding and spotting in • the first several months of use This side effect is experienced by 30% of women after two years of use Complaints of menstrual problems, including amenorrhea, missing periods, and spotting decline after one year and are less common among patients older than 30 Hormonal side effects (including headache and skin and hair changes) Physical methods Intrauterine methods Physical methods Ormeloxifene Ormeloxifene (Centchroman) • Ormeloxifene (Centchroman) is a selective • estrogen receptor modulator, or SERM. It causes ovulation to occur asynchronously with the formation of the uterine lining, preventing implantation of a zygote. It has been widely available as a birth control method in India since the early 1990s, marketed under the trade name Saheli. Centchroman is legally available only in India Physical methods Ormeloxifene Physical methods Emergency contraception Some combined pills and POPs may be • taken in high doses to prevent pregnancy after a birth control failure (such as a condom breaking) or after unprotected sex. Hormonal emergency contraception is also known as the "morning after pill," although it is licensed for use up to three days after intercourse. Physical methods Emergency contraception Copper intrauterine devices may also be • used as emergency contraception. For this use, they must be inserted within five days of the birth control failure or unprotected intercourse. Emergency contraception appears to work • by suppressing ovulation. However, because it might prevent a fertilized egg from implanting some people consider it a form of abortion. The details of the possible methods of action are still being studied. Physical methods Sterilization for male& femle Surgical sterilization is available in the form of • tubal ligation for women and vasectomy for men. Sterilization should be considered permanent. In women, the process may be referred to as "tying the tubes," but the Fallopian tubes may be tied, cut, clamped, or blocked. This serves to prevent sperm from joining the unfertilized egg. The non- surgical sterilization procedure, Essure, is an example of a procedure that blocks the tubes, wherein micro-inserts are placed into the fallopian tubes by a catheter passed from the vagina through the cervix and uterus. Physical methods Sterilization Although sterilization should be • considered a permanent procedure, it is possible to attempt a tubal ligation reversal to reconnect the Fallopian tubes in females, or a vasovasostomy by which vasectomies are reversed in males. The rate of success depends on the type of sterilization that was originally performed and damage done to the tubes as well as the patient's age Physical methods Barrier methods Condom (rolled-up). • Barrier methods place a physical • impediment to the movement of sperm into the female reproductive tract. The most popular barrier method is the • male condom, a latex or polyurethane sheath placed over the penis. The condom is also available in a female version, which is made of polyurethane. Physical methods Barrier methods The female condom has a flexible ring • at each end — one secures behind the pubic bone to hold the condom in place, while the other ring stays outside the vagina. Cervical barriers are devices that are • contained completely within the vagina. Physical methods Barrier methods The contraceptive sponge has a depression to hold • it in place over the cervix. The cervical cap is the smallest cervical barrier. Depending on the type of cap, it stays in place by suction to the cervix or to the vaginal walls. The diaphragm fits into place behind the woman's pubic bone and has a firm but flexible ring, which helps it press against the vaginal walls. Spermicide may be placed in the vagina before • intercourse and creates a chemical barrier. Spermicide may be used alone, or in combination with a physical barrie Physical methods Barrier methods Physical methods Barrier methods Behavioral methods Behavioral methods involve regulating • the timing or methods of intercourse to prevent the introduction of sperm into the female reproductive tract, either altogether or when an egg may be present. Behavioral methods Fertility awareness • Symptoms-based methods of fertility • awareness involve a woman's observation and charting of her body's fertility signs, to determine the fertile and infertile phases of her cycle. Behavioral methods Coitus interruptus • also known as the withdrawal or pull-out • method, is the practice of ending sexual intercourse ("pulling out") before ejaculation. Lactational • From ancient times women tried to extend • breastfeeding in order to avoid a new pregnancy.
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