Reducing the Chance of Unintended Pregnancy as much as 95%


More Frequently Asked Questions

Emergency Contraception (EC) consists of several different ways to safely prevent pregnancy following unprotected intercourse (UPI). Other terms for EC such as morning after pill, post-coital contraception, abortion pill, and the day after pill can be confusing. The most effective method of Emergency Contraception is the placement of an Intra Uterine Device (IUD) into the intrauterine cavity up to 7 days after UPI. Thus the preferable term should be Emergency Contraception. Although there are several methods of Emergency Contraception, only three methods are available in the U.S. at this time: 1) combined estrogen and progestin oral contraceptives, 2) the progestin-only pill such as Plan B which contains only levonorgestrel, or 3) the copper containing IUD.

An estimated 6.2 million pregnancies occurred in the United States in 2001. Approximately 50% of them were unplanned or unwanted. Of the 3.1 million unwanted pregnancies, nearly 1.2 million of those patients chose to have a termination of pregnancy. Today, there are legal and safe methods available that can reduce the incidence of unwanted or unintended pregnancy by 75 to 90% using progesterone-only or combined estrogen and progesterone medications. Of those 3.1 million unwanted pregnancies, 310,000 to 775,000 could have been avoided had EC been used within 72 hours of unprotected intercourse. If the medications are taken within 24 hours, there is close to a 95% reduction in the incidence of pregnancy which means the unplanned pregnancy rate would be even lower. Recent studies also indicate that anti-inflammatory medications (Indocin, Meloxicam) are able to inhibit or delay ovulation on their own. When combined with progestin-only medication, there is a two-fold increase in delay of ovulation compared to using progestin alone. This would reduce the risk of unwanted pregnancies greater even than 75 to 90%. If the Morning After Pill, or Emergency Contraception, or the Day After Pill was more readily available for women there would be a significant reduction in the number of unwanted pregnancies in the United States.

The anti-progestin RU486 which is also called Mifeprex, Abortion Pill, French Pill, or Mifepristone is used in the U.S. only for the purpose of inducing abortion. It has been found to prevent breast cancer, treat uterine fibroids, depression and schizophrenia. It is used in China as the primary means of Emergency Contraception; which if taken within 24 hours of unprotected intercourse, provides up to a 95% reduction in the incidence of pregnancy.

The Intrauterine Device has the potential to reduce the incidence of unwanted pregnancy by 99%. If the 3.1 million women with unwanted pregnancies would have had an IUD placed within 5 days of unprotected intercourse, that number could have been reduced to only 31,000.

If the morning after pill became available to all women who do not want to become pregnant, it would vastly reduce the incidence of maternal morbidity and mortality, along with the great number of unwanted pregnancies. Women should be able to control their own bodies. The financial savings for the individual patients, their families, and state and federal governments would total into the millions of dollars. Now, more than ever, is the time to educate as many women of reproductive age as possible about the benefits of Emergency Contraception.

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History of Emergency Contraception

The first major trial performed with modern contraceptive methods for emergency purposes was carried out at Yale University in 1963 using Diethylstilbestrol (DES) 25-50mg/day or ethinyl estradiol .5-2mg/day for 4-6 days following unprotected intercourse. No pregnancies occurred among the first 100 cycles reported. It was not until the mid-70’s when larger studies conducted in Holland with estrogens alone and in Canada with the estrogen-progestin combination lead the way for this method to become more readily available. Attempts to develop a progestin-only post-coital contraceptive method for regular use provided the basis for its application as emergency contraception today. In addition, the insertion of the Intrauterine Device (IUD) and the administration of the antiprogestin RU486, and the recently approved Ella (Ulipristal Acetate or Ellone) are all being used to prevent unwanted pregnancies in emergency situations.

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About Emergency Contraception

Emergency Contraception (EC) requires one or a combination of several options: 1) taking a set of birth control pills, 2) taking the anti progestins RU486 (Mifeprex) and Ella (Ulipristal Acetate or Ellaone), 3) taking Plan B or levonorgestrel, 4) taking anti-inflammatory medications (specifically COX 2 inhibitors) or 5) the placement of an Intrauterine Device (IUD) inside the uterus after unprotected intercourse.

When using birth control pills, Mifeprex, or Plan B alone for EC, the greatest chance of reducing pregnancy by 75 to 90% occurs if taken within 72 hours after intercourse. Recent studies show EC with birth control pills may be effective up to 120 hours (5 days) after intercourse. As stated above, the use of anti-inflammatory medications have been found to stop or delay the release of an egg from the ovary for several days, and in doing so prevents pregnancy from occurring. The IUD has shown to be nearly 100% effective in preventing pregnancy if inserted 5 to 7 days or less after unprotected intercourse. RU486 has been studied for several years in Europe and China as an emergency contraceptive method and has been shown to be as effective as, or even more than birth control pills, or Plan B (levonorgestrel).

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Emergency Contraception Statistics

In 1999, the first progestin-only pill (Plan B, levonorgestrel) was approved for use as emergency contraception. Despite emergency contraception’s safety, effectiveness and unique ability to reduce unintended pregnancy, it continues to be vastly underused. One study conducted in 1997 found that only one in ten health professionals routinely discussed emergency contraception with their patients, and that 41% of Americans were completely unaware of its existence. The only way to reduce the 3.1 million unintended pregnancies is to reduce the incidence of unwanted or unintended pregnancies from occurring in the first place. Emergency Contraceptive methods should be widespread and routinely provided from Family Planning Clinics, Private Physician Offices and Pharmacies; and readily available on College and High School campuses at little or no cost so that any woman exposed to unprotected intercourse has total access to preventing pregnancy. There are a lot of misconceptions about pregnancy with young teenagers and older women. Many teens who have never had sex believe that they can’t get pregnant unless they have an orgasm, and numerous women over 40 believe that their risk of becoming pregnant is lower because of their age.

Concerted efforts are being implemented to reduce the incidence of unwanted and unintended pregnancies by increasing access to contraceptive information and services and by broadening the range of health care professionals and institutions that promote and provide contraceptive services. At our Women’s Centers, the dispensing of emergency contraception is not a trivial matter. Patients are screened for health risks, informed about Sexually Transmitted Diseases (STDs) and taught methods of prevention. They are also encouraged to start some form of long term birth control and maintain Emergency Contraception at home because Emergency Contraceptive Pills are most effective when taken immediately after the event. Emergency Contraception does not protect against STDs or HIV and therefore the use of barrier contraceptive methods (female or male condoms) are always emphasized to patients.

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Why is Emergency Contraception So Important? 

Emergency contraception is vitally important for the 4.6 million women at risk of unwanted pregnancy because they cannot afford birth control or are unable to obtain health insurance; or because of rape, forced intercourse by their husbands or significant others, and any other reason that prevents them from having access. Emergency contraceptives do not protect against sexually transmitted diseases, but they do offer reassurance to millions of women who rely on condoms for protection against pregnancy in case of condom slippage or breakage.

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When is Emergency Contraception Indicated?

EC may be required in many situations. Following rape or sexual assault; for use with the withdrawal method; after consensual sex when no contraception was used; from not taking oral contraception appropriately; after ejaculation occurs unexpectedly near or on the external genitalia; when a condom breaks, leaks, splits or is retained in the vagina or incorrectly used; when a cervical cap or diaphragm is incorrectly inserted, damaged, dislodged or not used with contraceptive gel or when removed within 6 hours of sexual intercourse.

There is no exact time in a woman’s menstrual cycle when there is no risk of pregnancy after unprotected sexual intercourse. This is particularly true for women who have irregular periods or those who are uncertain of their last period. Over 30% of women studied did not know exactly when the fertile period was in their menstrual cycle.

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Emergency Contraceptive Pills (ECPs)

There are three types of ECPs: combined ECPs containing both estrogen and progestin, progestin-only ECPs, and ECPs containing an antiprogestin (either mifepristone or ulipristal acetate). Even though mifepristone (RU486) is available and FDA approved in the United States to induce abortion, it is not approved for use as an emergency contraceptive. Normally medications that are FDA approved can be used for other medical indications. In the United States, due to a special approval process, mifepristone can only be used to induce abortion. RU486 is commonly used in China as an emergency contraceptive and in random studies has been shown to be more effective than Plan B in preventing pregnancy using as little as 10 mgs orally if taken within 96 hours of unprotected intercourse. Only the combined estrogen and progesterone birth control pills (Yuzpe method) and progesterone-only pill called Plan B (levonorgestrel) are available for use in the U.S. as ECPs. The newer progesterone-only ECPs have now largely replaced the older combined ECPs because they are slightly more effective and cause less side effects. Although this therapy is commonly known as the morning after pill or the day after pill, these terms are misleading. ECPs may be initiated sooner than the morning after. They can be taken immediately after unprotected intercourse when they are most effective (up to 95% reduction in pregnancy rate) or up to 120 hours (50 to 75% reduction in pregnancy rate) after unprotected intercourse.

Combined ECPs contain the hormones estrogen and progestin. The hormones that have been studied most extensively in clinical trials of ECPs are the estrogen ethinyl estradiol and the progestin levonorgestrel or norgestrel. This combination of active ingredients used in this way is also known as the Yuzpe method, named after the Canadian physician who first described the regimen in 1974 when he used 100ug of ethinyl estradiol and 1mg of norgestrel in 143 patients in 148 cycles. There were three pregnancies noted and no side effects. His second study in 1977 consisted of 608 women who were treated with 200ug ethinyl estradiol and 2mg norgestrel in which only 1 patient became pregnant even though it was calculated that 12 to 30 patients should have conceived. A recent meta-analysis found effectiveness rates of 56 to 89% with a weighted average of 74% for reducing pregnancy based on the time of the cycle in which intercourse takes place. Using this Emergency Contraceptive method, only 2% of patients actually become pregnant.

When dedicated ECPs are not available, certain ordinary birth control pills can be used in specified combinations as emergency contraception. In either case, the regimen is one initial dose followed by a second one 12 hours later with each dose consisting of one to six or more tablets, depending on the brand. Currently, 23 brands of combined oral contraceptives are approved in the United States for use as emergency contraception. Newer research has demonstrated the safety and efficacy of an alternative regimen containing ethinyl estradiol and the progestin norethindrone. These results indicate that oral contraceptive pills containing progestins other than levonorgestrel may be additionally used for emergency contraception. The Yuzpe method of EC is slowly being replaced by progesterone-only ECPs (Plan B, levonorgestrel) because the latter are more effective in reducing pregnancy with fewer side effects. Common side effects of the Yuzpe EC method are nausea, vomiting, abdominal pain, headaches, diarrhea, breast tenderness, fluid retention, changes in timing and the amount of menstrual flow, emotional sensitivity, not sleeping, or irritability, but usually last only 1 or 2 days.

Progesterone-only ECPs do not contain estrogen. They contain levonorgestrel which has been studied extensively for use as an emergency contraceptive. The original treatment approved by the FDA in the U.S. used one initial 0.75mg dose within 72 hours after unprotected intercourse, followed by a second 0.75mg dose 12 hours later. Recent studies have shown that a single dose of 1.5mg is as effective as two 0.75mg doses 12 hours apart. One of these studies showed no difference in side effects between the two regimens, while the other found only greater levels of breast tenderness and headaches among participants taking 1.5mg of levonorgestrel at once. Increasingly, levonorgestrel is marketed internationally in a one-dose formulation (one 1. mg pill) rather than the two-dose formulation (two 0.75mg tablets, taken 12 hours apart). In the United States there are now two progesterone-only regimens approved for EC. The first is Next Choice, which was approved by the FDA in June 2009, and Plan B One-Step, approved in July 2009. This has replaced the two tablets of .75mg of levonorgestrel given 12 hours apart (Plan B) which was approved in July, 1999.

A random, double blind clinical trial compared levonorgestrel (Plan B) to the Yuzpe regimen in over 2000 women who were treated within 72 hours of unprotected intercourse. The crude pregnancy rate was 1.1% in the levonorgestrel group and 3.2% in the Yuzpe group. The pregnancy rates were .4%, 1.2%, and 2.7% when levonorgestrel was given within the first, second, or third 24-hour period after unprotected intercourse. This clearly shows that the sooner Emergency Contraceptive Pills are given, the more effective they are at decreasing the incidence of an unwanted pregnancy.

Levonorgestrel may be used more than once in a cycle if clinically indicated. Giving repeat doses of levonorgestrel prior to the LH (Luteinizing Hormone) surge may be effective and further unprotected sexual intercourse may be an indication for repeated levonorgestrel use. Repeated use will not induce abortion if the woman is already pregnant. The consensus view is if unprotected intercourse occurs within the 12 hours of taking the completed dose of ECPs, further treatment for ECPs is not necessary.

It is important to understand that Plan B or progesterone-only pills do not cause abortion which is defined as removal of the implantation of a fertilized egg from the intrauterine wall. Multiple studies have shown that neither progesterone-only pills nor combined estrogen and progestin pills inhibit implantation of a fertilized egg based on the fact that on the day of ovulation or slightly after ovulation, there is no reduction in the incidence of pregnancy. There is no evidence of progestin-only or combined hormonal contraceptives causing harm to a developing embryo, blastocyst, or fetus. The FDA long ago allowed the removal of information on the package insert of birth control pills stating they were harmful to the fetus or affected the pregnancy in any manner. The few studies of infant growth that have been conducted with progestin-only and combined estrogen and progestin oral contraceptive pills have not demonstrated significant adverse effects.

RU486 is known as an antiprogestin, and has a high affinity with progesterone receptors. It competes with progesterone for the progesterone receptors. Progesterone is a female hormone that serves several fundamental functions in the fertilization process. There are several actions that RU486 has in preventing ovulation, fertilization, transportation of the ova, and implantation: 1) Inhibition of ovulation due to midcycle gonadotropin surge by acting directly on the pituitary, or inhibiting the positive feedback effect of estrogens which blocks or delays the preovulatory LH surge responsible for the growth of the dominate follicle which when temporarily arrested and ovulation delayed or blocked when RU486 is given in the follicular phase it affects cytokines and prostaglandins thought to be involved in the rupture of the follicular wall. Under these circumstances, sperm derived from the single act of unprotected intercourse have to wait too long for the oocyte to be released and fertilization to take place. 2) Fertilization. The egg has only a very narrow window for fertilization to take place once the LH surge occurs and it is released. After that, the egg begins to disintegrate and is no longer able to become impregnated by healthy sperm. 3) Corpora luteal Function. Absence of progesterone causes invasion of the corpus luteum by macrophages that would result in a reduction or disappearance of the luteal cell population in which progesterone is important for transportation of the ovum through the oviduct and preparation of the lining of uterus (endometrium) for implantation and decidualization to take place. Without the presence of a corpus luteum, and the lack of progesterone, then adequate transportation, implantation, and decidualization does not occur. 4) Transportation of the ova through the fallopian tube and uterus is deficient and 5) deficiency in the development of the uterine endometrium into secretory endometrium and decidualization of the endometrium prevents implantation and continuation of a pregnancy.

Several studies have shown that administration of mifepristone during the luteal phase (after ovulation occurs) interferes with the development of a normal secretory endometrium causing ultrastructural changes in decidual capillaries, vascular damage and decidual necrosis. Presumably, these alterations should prevent or disrupt implantation.

Any disruption to the progesterone receptor or amount of progesterone available could lead to an adverse effect on ovarian follicular development, implantation of a fertilized egg, and pregnancy maintenance where progesterone causes uterine quiescence. Withdrawal, lack or blockage of progesterone receptors leads to increase in uterine pressure and uterine contractions which leads to spontaneous miscarriage.

The antiprogestin mifepristone (Mifeprex or RU486) has been studied extensively in China for use as an emergency contraceptive pill. A recent study that included over 1700 women showed a pregnancy rate of 1.2% using 10 mg of RU486. This translates into 84 to 86%t of expected pregnancies were prevented. Only 12% of patients had nausea, headache, or dizziness. In nearly half of the cases, the next menstrual period came later than expected. Mifepristone is a first-generation progesterone receptor modulator that is approved for use in many countries for early first-trimester medication abortion. Mifepristone delays menstruation by a mean of 42 days with a range from 33 to 51 days. Mifepristone has been shown to be highly effective for use as emergency contraception, with few side effects which include mild nausea and abdominal pain, constipation, diarrhea, mild headache, and early or delayed menstruation. Mifepristone has promise in prevention of reduce symptoms of fibrocystic disease of the breast, breast cancer, ovarian cancer, and to treat large uterine fibroids. Mifepristone delays ovulation and changes the intrauterine and tubal environment such as to prevent tubal transport of the sperm and or egg; prevent implantation from occurring, and can also dislodge (detach) a pregnancy from the wall of the uterus. It is this latter mechanism of action of being an abortifacient medication, and it is well known as the “abortion pill” that leads it to be unpopular in the US and many other countries around the world as an EC. A second generation progesterone receptor modulator, ulipristal acetate (30 mg in a single dose) has been found to be highly effective with very few side effects. It has been approved and marketed for use as emergency contraception in the US since 2010 and in Europe since October 2009.

As little as 10 mg of RU486 administered as a single dose within 72 hours of intercourse, has been found to be as efficacious as the Yuzpe method or Plan B (levonorgestrel). Also, compared with the Yuzpe method and Plan B, patients using RU486 had low rates of nausea and vomiting. Though women using Yuzpe had a higher incident of irregular bleeding, those using RU486 were noted to have a delay in their normal menses. Because of this delay, intercourse should be avoided and the patient reassured that a postponed cycle may not be secondary to a pregnancy. If menses has not occurred with 3 weeks, a pregnancy test should be performed.

RU486 should be approved or should be able to be used in the United States as an EC. The use of RU486 as an effective single-dose post-coital contraception agent will help to increase patient compliance, decrease adverse symptoms, and therefore help to decrease the incidence of medical and surgical abortions and the social implications brought on by the delivery of an unwanted pregnancy.

There have been studies that compared the efficacy of 10 mg mifepristone and 1.5 mg levonorgestrel use for emergency contraception. Two studies found no significant difference in efficacy of the two-dose (0.75 mg each) levonorgestrel regimen and mifepristone; pregnancy rates for the two regimens were respectively 1.8% and 1.5% in the first trial and 2.0% and 1.3% in the second. The first trial also included a one-dose (1.5mg) levonorgestrel regimen, which yielded a pregnancy rate of 1.5%. An earlier trial showed a significant difference between pregnancy rates for the two-dose levonorgestrel regimen (3.1%) and the 10 mg mifepristone regimen (1.4%). Several studies of recent Chinese randomized trials found that 25 mg to 50 mg dosages of mifepristone had a lower failure rate than did levonorgestrel, but the delay in menses for the two regimens was similar.

Two randomized trials compared the efficacy of levonorgestrel with ulipristal acetate, one up to 72 hours after unprotected intercourse and the second up to 120 hours after. When these two studies were combined, ulipristal acetate was found to have a pregnancy rate 42% lower than levonorgestrel up to 72 hours and 65% lower in the first 24 hours. In the second randomized study, 30 mg ulipristal acetate prevented significantly more pregnancies than did levonorgestrel in the 72-120 hour subgroup. The reason seems to be that ulipristal acetate can prevent ovulation when taken closer to ovulation than can levonorgestrel. By the time the follicle (the primary egg that will be released for possible pregnancy) reaches 18-20 mm (and ovulation should occur within 48 hours) and the probability of conception > 80%, ovulation is prevented by levonorgestrel in only 12% of cycles (versus 13% in the placebo group). In contrast, ulipristal prevents ovulation in 59% of cycles.

There are now multiple studies that show that levonorgestrel does not prevent ovulation from taking place if the timing of taking it is too close to the time that ovulation is supposed to take place and has no statistical effect on the effect of pregnancy after that point. This point is emphasized in particular because of the continuing thought that Plan B causes abortions in which there is no data to support such claims.

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Using Non-Steroidal Anti-inflammatory Drugs for Emergency Contraception:

In the preovulatory follicle (the egg that will be released from the ovary), the Lutenizing Hormone (LH) surge causes gene expression a many proteins which result in changes in concentrations of many ovulatory mediators (signals that cause ovulation to take place) within the follicle including prostaglandins which lead to follicle wall rupture that occurs prior to release of the egg which is ovulation. It is not quite clear the exact mechanism of action that prostaglandins play in leading to the ovulation process. Effects on follicular blood flow or the breakdown of collagen have been suggested. The rate limiting step to prostaglandin synthesis is cyclooxygenase which exists in two isoforms, cyclo-oxygenase (COX)-1 and COX-2. The latter is generated in response to inflammatory stimuli or in response to LH. Without the LH surge that takes place mid-cycle, ovulation would not take place.

Prostaglandins are also responsible for release of the follicle (egg) from the ovary. Without a local inflammatory process taking place around the ovary in which prostaglandins are involved, ovulation will be delayed or will not occur.

Meloxicam (Mobic) is a non-steroidal anti-inflammatory medication (NSAID) that exhibits anti-inflammatory, analgesic, and antipyretic activities. It is a cyclooxygenase 2 (COX-2 inhibitor) and prevents the formation of prostaglandins which is responsible for causing inflammation to occur.

Meloxicam inhibits cyclooxygenase (COX) specifically COX-2 which prevents prostaglandin synthetase from producing prostaglandin which in turn reduces inflammation. By reducing inflammation in the body, it reduces pain and swelling. Thus the reason for using anti-inflammatories for painful joints, fever, headaches, and muscle aches, etc.

Studies show that giving Meloxicam 30 mg for five consecutive days, Indomethacin 50mg three times a day for three days, Vioxx 20 mg every day for 5 days in the late follicular phase of ovulation appears to be an effective emergency contraceptive option. This regimen does not alter the endocrine profile of the cycle and causes no menstrual disturbance. Prevention of follicular rupture has been delayed from 2 to 12 days with the Indomethacin protocol, and the other anti-inflammatories are very similar in the length of the delay of follicular rupture. This delay in rupture leads to the aging of the egg to the point that when or if it is released, it is no longer able to be fertilized as the mature egg only has a 12 to 24 hour period when it is able to be fertilized. All of the hormones remain normal (FSH, LH progesterone, and estrogen) so in essence there is no prolonging or shortening of the menstrual cycle as seen with the progestin-only, combined estrogen and progesterone, or anti-progestin medications.

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Copper T IUD for Emergency Contraception

The Emergency IUD should be offered to all women who present for emergency contraception even if within 72 hours from unprotected intercourse as it has the lowest failure rate. It should be offered particularly to those women who intend to continue the IUD as long term contraception.

The Copper T IUD is the most effective means of Emergency Contraception as it is over 99% effective if it can be inserted up to the time of implantation—five to seven days after ovulation—to prevent pregnancy. Thus, if a woman had unprotected intercourse three days before ovulation occurred in that cycle, the IUD could prevent pregnancy if inserted up to ten days after intercourse. Because of the difficulty in determining the day of ovulation, however, many protocols allow insertion up to only five days after unprotected intercourse. The latest WHO guidelines allow IUDs to be inserted up to day 12 of the cycle with no restrictions and at any other time in the cycle if it is reasonably certain that the patient is not pregnant. A copper IUD can also be left in place to provide effective ongoing contraception for up to ten years. But IUDs are not ideal for all women. Women with current sexually transmitted diseases (STD’s) are not good candidates for IUDs; insertion of the IUD in these women can lead to pelvic infection, which can cause infertility if untreated. Women not exposed to STD’s have little risk of pelvic infection following IUD insertion, and use of a copper IUD is not associated with an increased risk of tubal infertility among nulligravid women (whereas infection with Chlamydia is).Other contraindications for the Copper T IUD are undiagnosed vaginal bleeding, PID within the last 3 months, uterine or cervical cancer, or Wilson’s Disease.

The major effect of all intrauterine devices (IUD) is to induce a local inflammatory reaction in the uterine endometrium. Copper ions released by copper IUDs enhance the inflammatory response and reach concentrations in the luminal fluids of the genital tract that are toxic for sperm and embryos. In women using the IUD, the entire genital tract seems affected, at least in part, because of luminal transmission of the fluids that accumulate in the uterine lumen. This affects the function, physiology or viability of gametes, decreasing the rate of fertilization and lowering the chances of survival of any embryo that may be formed, even before it reaches the uterus. Studies on the recovery of eggs from women using IUDs and from women not using contraception show that embryos are formed in the tubes of IUD users at a much lower rate compared with nonusers. This appears to be the major action of IUDs. Therefore, the common belief that the major mechanism of action of IUDs in women is through destruction of embryos in the uterus (abortion) is not supported by the available evidence. The few sperm that reach the distal segment of the fallopian tube are likely in such poor condition when they encounter an egg so that if the egg is fertilized, there is little chance for development and the possibility for survival in the altered tubal mileau (inflammation) becomes worse as they approach the uterine cavity. It is also accepted that the IUD has an anti-implantation effect but is not an abortifacient.

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Emergency Contraceptive Effectiveness

Accurate estimates of efficacy depend upon accurate recording of timing of intercourse and cycle day (so that timing of ovulation can be estimated). One study compared self-report of cycle day with urinary pregnanediol concentrations to demonstrate that over 30% of women presenting for ECPs had inaccurately dated their own menstrual cycles, believing themselves to be in the fertile phase of their cycle when they were not. Approximately 60% reported more than one act of unprotected intercourse during the same cycle. This is suggestive that a certain percentage of failure from ECPs is due to earlier intercourse in the cycle which leads to the patient already being pregnant when she takes the ECPs. A separate study noted that 99 women who reported being in the late follicular or early luteal phase of their cycles (a few days before ovulation or the day after ovulation) between days -5 and +1 when the day of ovulation (day 0) was estimated as usual cycle length minus 13. Hormones were also drawn at the time these patients presented for emergency contraception and it showed that only 56% percent of those patients, 51 of the 99 were actually between days -5 and +1. I a separate study, cervical smears taken showed that a little more than 30% of women requesting ECPs had no sperm present in the vagina, and those with sperm present had fewer sperm than women attempting to become pregnant. In essence, with no or sperm counts below a certain number, fertilization cannot take place. The data shows that taking levonorgestrel within 72 hours of unprotected intercourse reduces the incidence of pregnancy by 75 to 90 % and if taken within 90 to 120 hours of unprotected intercourse will reduce the pregnancy rate by 63%. If taken less than 24 hours after unprotected intercourse, Plan B (levonorgestrel) reduces the incidence of pregnancy by 95%. No data is available on the efficacy of ECPs if they are taken greater than 120 hours after intercourse.

RU486 or Mifeprex reduces the incidence of pregnancy by 95% in less than 24 hours after unprotected sex and while taking it between 24 and 48 hours later prevents 85% of unwanted pregnancies. The same study also found that 1/3 or women under 16 years old and 2/3 of women over 16 needed the morning after pill because of contraceptive failure (broken condom or missed oral contraception).

A pilot study of 41 women found that adding a Cox-2 inhibitor (meloxicam 15 mg) to 1.5 mg levonorgestrel significantly increased the proportion of cycles with no follicular rupture or ovulatory dysfunction compared to just levonorgestrel alone (88% vs. 66%). Adding a Cox-2 inhibitor can disturb the ovulatory process after the onset of the LH surge whereas levonorgestrel has its effect on preventing the LH surge and inhibiting or delaying ovulation prior to the LH surge. Once the LH surge occurs, levonorgestrel cannot prevent ovulation from occurring.

More than 12,000 post-coital insertions of copper-bearing IUDs are known to have been carried out since the practice was introduced in 1976. With only 12 failures, this approach has a pregnancy rate of 0.1%. The effectiveness of using a levonorgestrel-releasing IUD (LNg-20) for emergency contraception has not been studied and is not recommended at this time.

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How Does Emergency Contraception Work?

Several studies show that ECPs containing the estrogen ethinyl estradiol and the progestin levonorgestrel can inhibit or delay ovulation. They do not appear to work after ovulation has taken place because there is no evidence that they reduce the incidence of pregnancies after ovulation. Recent studies have found no effects on altering the lining of the endometrium (uterine lining) that would prevent implantation of a fertilized egg. Other mechanisms of action of ECPs have been studied to include interference with corpus luteum function which produces progesterone and is important up to the eighth week of pregnancy to maintain uterine quiescence. Otherwise, the uterus would contract and expel the pregnancy tissue. Other possible ways that ECPs could work are thickening of the cervical mucus which would prevent sperm from entering the uterus and fallopian tubes; interfere in transport of the egg, sperm, or embryo in the fallopian tube, or prevention of fertilization, or embedding of the fertilized egg from taking place. There is no evidence of that the last four mechanisms mentioned happen with combined ECPs.

Treatment prior to ovulation with progesterone-only ECPs (levonorgestrel) prevents or delays ovulation from occurring. Just like with combined estrogen and progesterone ECPs, there is no effect on the endometrium that occurs. There is no evidence that levonorgestrel works after the ovulatory process starts with the LH surge. If it was to work, there would be a reduction in the calculated pregnancy rate after this time and there is not.

An established pregnancy is defined as beginning with implantation of the fertilized egg in the lining of the endometrial cavity. This definition is agreed upon by several authorities in the United States: 1) American College of Obstetrics and Gynecology, 2) Food and Drug Administration. Therefore, ECPs are not abortifacient (cause abortion).

Antiprogestins work by 1) inhibiting ovulation, 2) changing the environmental milieu of the endometrium to either prevent implantation of a fertilized ovum or separation of the pregnancy from the uterine wall, and 3) causing increase in intrauterine pressure and uterine contractions leading to spontaneous miscarriages.

Anti-inflammatory medications work by 1) inhibiting ovulation from occurring even after the LH surge has occurred, 2) inhibit fertilization from taking place due to the protein layer that surrounds the ovary has COX-2 present and an increase in this rate limiting step leads to an increase in prostaglandin E2 which is essential for sperm penetration to take place. Studies using PGE receptor EP2-deficient mice revealed that Prostaglandin E2 (PGE2) cooperates with gonadotropins (FSH and LH) to complete cumulus expansion (area surrounding the ovary that contains COX-2 that is necessary to produce PGE2) for successful fertilization. 3) prevents implantation from taking place as prostaglandins are important on the lining of the endometrium and the pregnancy itself. Without the presence of prostaglandins, implantation cannot occur, 4) decidualization of the lining of the endometrium. This is where the endometrium forms stroma and glands that are necessary for the pregnancy to remain attached to the uterine wall and what is necessary for pregnancy growth to take place.

It is also known that Prostaglandins along with Histamines serve a role in the implantation of a fertilized egg into the uterine wall thus causing pregnancy to take place. The mechanism of action of how the implantation process is not totally clear. In recent research done in India, it was found that giving the Histamine (H2) blocker Ranitidine in a dose of 70mg/kg and the NSAID COX-inhibitor Meloxicam in a dose of 4mg/kg in albino Wistar Rats, there was 100% anti-fertility activity. Whether this inhibition of histamine and prostaglandin activity occurring in the uterus prevents implantation in humans remains to be seen.

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How Safe is the use of Emergency Contraceptives?

Emergency Contraception has never been linked to any short or long term complications. There are no contraindications to the use of ECPs according to the World Health Organization (WHO). Given the very short duration of exposure and low total hormone content, combined ECP treatment can be considered safe for women who would ordinarily be cautioned against use of combined oral contraceptives for ongoing contraception. No changes in clotting factors have been detected following combined ECP treatment. Levonorgestrel or insertion of a copper IUD may be preferable to use of combined ECPs for a woman who has a history of stroke or blood clots in the lungs or legs and wants emergency contraception.

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What Are the Side Effects Of Emergency Contraception? 

The most common side effects of ECP’s include headache, abdominal pain, diarrhea, constipation, breast tenderness, dizziness headache, nausea and vomiting which generally only last a few hours but can remain a few days after taking the medications.

About 50% of women who take combined ECPs experience nausea and 20% vomit. If vomiting occurs within 2 hours after taking a dose, some clinicians recommend repeating that dose. Most Physicians and providers suggest that the ECPs be taken with food to help reduce the incidence of nausea and vomiting. Using the progestin only Levonorgestrel for EC has a much lower incidence of nausea and vomiting than the combined regimen. A randomized controlled trial conducted by WHO, progestin-only ECPs are associated with an incidence of nausea 50% lower and an incidence of vomiting 70% lower than that for combined ECPs. In another study, levonorgestrel was associated with vomiting in only 1% of women and nausea in 14% of women who took it for EC. Women who experience vomiting within 2 hours of administration of levonorgestrel EC should be advised to return as soon as possible for a repeat dose. If a woman experiencing persistent vomiting with oral EC, an IUD should be considered.

The non-prescription anti-nausea medicine meclizine has been demonstrated to reduce the risk of nausea by 27% and vomiting by 64% when 50 mg tablets are taken 1 hour before combined ECPs. The major side effect from taking the meclizine is drowsiness.

There have been studies designed to determine the effects of ECPs consisting of levonorgestrel on uterine bleeding patterns. One study found that when taken in the first three weeks of the menstrual cycle, ECPs significantly shortened that cycle as compared both to the usual cycle length and to the cycle duration in a comparison group of similar women who had not taken ECPs. The earlier that levonorgestrel is taken in the cycle, the shorter the cycle length was noted. The magnitude of this effect
was greater the earlier the pills were taken. If levonorgesterel was taken later in the cycle, there was no effect on the length of the current cycle, but the following menstrual cycle was prolonged.

Intermenstrual bleeding was uncommon after ECP use, although more common than among women who had not taken ECPs. In a World Health Organization (WHO) trial, 16% of women experienced intermenstrual bleeding (bleeding not related to normal menses) in the 7 days following treatment. Around 50% of women menstruated a few days earlier or a few days later that their expected time.

In another study that compared the baseline cycle with the treatment and post-treatment cycles, cycle length was shortened by one day when ECPs were taken in the preovulatory phase of the cycle and was significantly lengthened by two days when ECPs were taken in the postovulatory phase. No difference in
cycle length was observed for women who took ECPs during the periovulatory phase of the cycle (from two days before to two days after the expected day of ovulation). Menstrual period duration increased significantly when ECPs were taken in the periovulatory or postovulatory phase in both the treatment and post-treatment cycles. The duration of the post-treatment menstrual cycle remained significantly longer when ECPs were taken in the postovulatory phase. During the treatment cycle, 15% of women experienced intermenstrual bleeding; this was significantly more common when ECPs were taken in the preovulatory phase.

The third study examined the effects of two 0.75 mg levonorgestrel pills taken 12 hours apart. When taken in the follicular phase, ECPs significantly shortened the cycle when compared with usual cycle length. No effect on length of cycle was found when ECPs were taken in the periovulatory or luteal phase. The post-treatment cycle length was the same as the usual cycle length.

Following levonorgestrel EC, more than 80% of women menstruate before, or within 2 days after their expected date; and 95% menstruate within 7 days after their expected date. Ectopic pregnancy or pregnancy should be suspected if menstruation does not occur after 7 days of the expected date or there is lighter bleeding.

Ectopic pregnancies have been identified following administration of Levonorgestrel EC in cases. The overall risk is not increased following taking Levonorgestrel.

Non-Steroidal anti-inflammatories (NSAID) are associated with nausea, abdominal pain, abdominal bloating, headaches, dizziness, light-headedness, skin reactions, and allergic reactions including death. Most patients know if they are allergic to aspirin or aspirin products and therefore know that they should not take any form of NSAID.

Mifeprex (RU486, Mifipristone, Abortion Pill) side effects include nausea, vomiting, and abdominal pain, headache, and dizziness, early or late onset of menses during present cycle that emergency contraception is taken with the latter being more common. These side effects are less frequent than those that occur with levonorgestrel.

Women should be advised that there is a 6 fold increase in pelvic infection that occurs in the first 20 days following IUD insertion, but the risk is the same as for the non IUD-using population thereafter. Despite this, the overall risk is extremely low with an overall rate of Pelvic Inflammatory Disease (PID) of 1.6 per thousand woman years. Prior to emergency IUD insertion, women at higher risk or STDs (age <25 years, change in sexual partner, or more than one partner in the past year) should be offered testing for Chlamydia Trachomatis). For women assessed as being at higher risk of STD’s, if results of testing are not available at the time of emergency IUD insertion, the use of prophylactic antibiotics may be considered.

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What aftercare and follow-up is required with the use of Emergency Contraception?

Women should be given information and counseling on use of their future contraceptive method of choice as neither combined ECPs nor progestin-only ECPs provide contraceptive cover for the remainder of the cycle and effective contraception or abstinence must be advised. After EC use because of “missed pills”, women should be advised to resume hormonal contraception within 12 hours of taking levonorgestrel EC. If the patient is not on a regular method of contraception, it should be discussed that women should initiate a regular method of contraception and can be started anytime in the present cycle if abstinence or condom use is unlikely. Women should be advised to have a pregnancy test if their expected menses is more than 7 days late, or lighter than usual.

A woman having an emergency IUD inserted may choose to keep it in place as a regular method of contraception. She should be advised to return 3 to 6 weeks after insertion to check for infection, perforation or expulsion. If symptoms of pelvic infection, pain, persistent menstrual problems, missed periods, or not able to feel the IUD thread occurs, the patient should be told to immediately seek medical attention. An emergency IUD can be removed at any time after the next menstruation if no unprotected sexual intercourse has occurred since menses or if hormonal contraception was started within the first 5 days of that cycle. In the case where a woman has not menstruated following emergency IUD insertion, the device can be removed after 3 weeks as long as it is pretty certain that she is not pregnant. If the IUD fails to prevent pregnancy, the IUD should be removed to reduce the incidence of an infection and or miscarriage.

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Does Emergency Contraception Cause any detrimental effects to a Pregnancy?

There is no evidence that Emergency contraceptive pills because any harm to the patient or the pregnancy if the patient was found to be already pregnant when she took the ECPs.

Several studies have evaluated the births to women who have continued taking oral contraceptives (combined or progestin only) without knowing they were pregnant have found no increased risk of birth defects. The FDA removed warnings about the negative effects of combined oral contraceptives on a pregnancy from the package insert several years ago.

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What effect do ECPs have on women that are Breastfeeding?

When patients are breastfeeding without additional substitution of other foods or drink, along with the woman having no menstrual cycle, it is rare for the woman to become pregnant for two years or longer. There are no restrictions on use of ECPs by breastfeeding women. After examining the pharmacokinetics of having taken 1.5 mg of levonorgestrel and the effect it has on breast milk and plasma of lactating women, it was concluded that mothers should discontinue breast feeding for a minimal of 8 hours to no more than 24 hours after taking ECPs.

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Liver Enzyme Inducing Drug Interactions

Women using liver enzyme inducing drugs should be advised that an IUD is the preferred option for EC. No specific data are available about the interactions of ECPs with other drugs, but it seems reasonable that drug interactions would be similar to those with regular oral contraceptive pills. Women taking drugs that may reduce the efficacy of oral contraceptives (including but not limited to rifampin, certain anticonvulsant drugs, Saint John’s Wort, and certain antiretroviral agents) should be advised that the efficacy of ECPs may be reduced. Women who are using liver enzyme inducing drugs who are given 1.5 mg tablets of levonorgestrel should be advised to take a total of 3mg as a single dose as soon as possible and within 72 hours of unprotected sexual intercourse. There are no drugs that are known to affect emergency IUD use.

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Why is there so much debate about Emergency Contraception? Why is it not well known or widely used?

There were many years where Emergency Contraception was practiced but there was no consensus on the safety of the practice or how effective the birth control pills were as there was very little data. So without any Pharmaceutical company being able to market a particular medication for Emergency contraception, there was never widespread knowledge of the safety or effectiveness of its usage in practice. There were no FDA approved medications in the US for EC until 1998 (Preven) which was taken off the market in 2004. Plan B was approved in 2005 but was never marketed by the companies that owned it on a large scale.

Since Physicians are not marketed to regarding Emergency Contraception and patients are not demanding it, then one can see why and how Emergency Contraception is not known about as it should be. It is up to Family Planning Services, private Physicians, Medical Clinics, Reproductive Family Planning clinics like the Women’s Center, and other associations whose focus is to reduce the number of unwanted pregnancies in the United States and the world to educate women and men about emergency contraception.

We counsel and offer all patients who visit our facilities about advanced Emergency Contraception in case they have unprotected intercourse. We feel the most effective way for the communities in which we serve to learn about Emergency Contraception is spread by word of mouth after patients are properly educated.

The majority of hospitals in the United States are owned or being taken over by Corporations that are Religious in origin which means that patients who present for contraception or Emergency Contraception are denied access. Many women go to emergency rooms to be examined after being sexually assaulted and aren’t even offered Emergency Contraception.

The Department of Defense Pharmacy and Therapeutics Committee removed ECPs from the Basic Core Formulary (BCF) (medications which must be stocked at every full-service Medical Treatment Facility (MTF)) in May 2002, only one month after the drug had been added to the BCF because of complaints from conservative members of Congress. In November 2009 the Pharmacy and Therapeutics Committee had a meeting where there was a request to approve Plan B one-Step (levonorgestrel) and add it as a core drug in Defense Department Health facilities. In Feb. 2010, levonorgestrel was added back to the formulary for American Soldiers serving in Afghanistan, Iraq, and other military facilities around the world. The current policy is that any woman who learns she is pregnant while in the war zone is immediately removed and sent back to the U.S. Now military women who have unprotected sex for any reason are able to prevent an unwanted pregnancy up to 90% of the time.

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What is the effectiveness of emergency contraception pills if primarily used as the only contraceptive method?

Emergency Contraception Pills should never be used as a primary means of contraception due to the high probability of becoming pregnant in a year. With using birth control pills on a daily basis, there is less than a 1 percent chance of becoming pregnant in a year. By using combined estrogen and progestin for EC there is approximately a 35 percent chance of becoming pregnant, and using the EC levonorgestrel, there is a 20 percent chance of becoming pregnant within the year. Therefore EC is a poor choice for primary contraception and is not to replace any method of continuous birth control.

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Making Plan B Over-the-Counter Emergency Contraceptive 

No medical reasons necessitate ECPs to be prescription-only products. Due to political pressure, it took several years for the FDA to approve the nonprescription sale of Plan B which was finally approved on August 24, 2006, for women and men aged 18 and older. Plan B One-Step was approved by the FDA as a nonprescription drug for women and men 17 and older in July 2009 (and Next Choice, a generic version of Plan B was approved in August 2009). Younger women (less than 16 years old) will still need a prescription to buy the drug. Plan B is kept behind the pharmacy counter, not on the shelf. The FDA decision is a small victory for some women. Access is still limited by whether a patient less than 17 years old has access to the medical system in order to get a prescription written, or if she is able to afford the price of the emergency contraceptive pill. The $35.00 to $65.00 cost is certainly a deterrent to most young teenagers. Pharmacist can refuse to dispense Plan B One-Step or Next Choice due to their religious feelings that pregnancy begins at the time of fertilization. Though theoretically levonorgestrel (Plan B or Next Choice) can prevent implantation, there is no scientific evidence that this has ever occurred. Yet this is used as a reason why certain Pharmacists refuse to give out Emergency Contraception Pills to prevent an unwanted pregnancy. The lack of privacy may be a barrier to access for women who as there is no area that women are able to discuss their reason for wanting ECPs in a private manner in the open pharmacy atmosphere. This leads to patients leaving which leads to delay in getting appropriate medical care.

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What are methods to allow patients access to emergency contraception information?

The most important step is to educate all reproductive age women about Emergency Contraception, and long term birth control measures. All women should be placed on birth control and be able to take home some form of emergency contraception in case their primary form of birth control fails. We at the Women’s Center have made it a priority to educate and teach patients about Emergency Contraception and their side effects so that they can choose which method they would like to take home as we know the most effective time to take the morning after pill, day after pill, post coital pill is within the first 24 hours of unprotected intercourse.

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Is Emergency Contraception Cost Effective? 

Prevention of unwanted pregnancies in the U.S. and around the world reduces the incidence of maternal and perinatal morbidity and mortality. It could same millions and perhaps billions of dollars of medical expenses from preventing termination of pregnancies to young patients who are susceptible to high risk pregnancies that include eclampsia, preeclampsia, premature labor, premature deliveries, and the complications associated with very low birth weight and low birth weight infants (Intraventricular Hemorrhage, necrotizing enterocolitis, electrolyte abnormalities, elevated bilirubin, sepsis, etc.)

In order for Emergency Contraception to make an impact by preventing unwanted pregnancies, it is assumed that patients will use ECPs immediately and in a timely fashion. It has been shown in several studies that a reduction in unwanted pregnancies and abortion does not occur because even when provided with ECPs in advance, women do not use the treatment often enough after the most risky incidents to result in a substantial reduction in pregnancy.

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Can The Cost of Emergency Contraception Be Prohibitive To Patients?

In order to reduce the incident of unwanted or unintended pregnancies in the U.S. and around the world, women must have the knowledge, access to long term birth control, and instant availability to Emergency Contraception if exposed to unprotected intercourse.

There are different types of emergency contraception ranging from hormonal, levonorgestrel or Plan B which is a progestin-only contraceptive, combined estrogen and progesterone birth control pills, or the Intrauterine Device (IUD). Using birth control as emergency contraception (combined estrogen and progesterone pills) can cost from $25.00 to $45.00, Plan B cost can range from $35.00 to $70.00, and the IUD cost and insertion can range from $400.00 to $700.00. The IUD is the most preferred method used for Emergency Contraception because of highly effective it is in preventing a unintended pregnancy and can be used as a reversible form of long term contraception for up to 12 years. It is the initial cost that can be prohibitive to a lot of patients, but over a 10 to 12 year period, it turns out to be the least expensive form of reversible birth control if it stays in the uterus for more than 2 years.

For patients below poverty, or young teenagers, coming up with an additional $35.00 to $70.00 can also be prohibitive and due to the high cost, they are unable to afford any form of contraceptives emergency.

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Emergency contraception has the potential to provide women with an opportunity to prevent an unwanted or unintended pregnancy after unprotected intercourse. It is unlikely that using ECPs alone to prevent unwanted pregnancies will prevent most unwanted pregnancies in the general population because 1) patients will forget to take the ECPs, 2) 40% of patients who use OCPs and 20% of patients who use levonorgestrel (Plan B) as Emergency Contraception and their primary means of contraception will become pregnant within a year, and 3) the incidence of unprotected intercourse is very high.

This is why using the most effective means of Emergency Contraception that we have today in preventing pregnancy (the Copper IUD) should be the first choice offered to all patients who present for Emergency Contraception. Not only for its short term effects, but for its prevention of pregnancy of over 99% up to 12 years if the woman chooses to keep it in place. There are only a few contraindications from using the IUD which are 1) pregnancy, 2) unknown vaginal bleeding, 3) cervical cancer or uterine cancer, 4) present pelvic or uterine infection, and 5) Wilson’s Disease. The incidence of infection increases slightly after the first 20 days of IUD insertion and then the risk of pelvic infection is the same as the general population. The IUD is the most commonly used method of birth control in the world and is extremely safe and highly efficient in protecting against pregnancy.

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