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Introduction

  1. Top of page
  2. Introduction
  3. Unwanted pregnancy—the global context
  4. What is emergency contraception?
  5. Who will use emergency contraception?
  6. Methods of emergency contraception
  7. How does emergency contraception work?
  8. Access and availability
  9. Conclusion
  10. References

The availability and use of emergency contraception has generated enormous debate and controversy since its inception in the 1960s. Recent concerns over teenage pregnancy, abortion and sexuality have pushed this method of contraception to the fore once again. Emergency contraception provides a safe and effective means of postcoital treatment and has been estimated to prevent at least 75% of expected pregnancy resulting from unprotected intercourse. However, use of the method is low, provision is patchy and knowledge is poor. The majority of studies are in the developed countries and mostly in the United Kingdom, with very little research in developing nations. General findings point to the fact that knowledge of emergency contraception is not wide and is under-utilised. Women are interested in preventing unintended pregnancies and further information and availability would facilitate such action. Knowledge of emergency contraception is crucial to its utilisation. Raising awareness about the methods and making it both easily available and accessible will improve its use. Emergency contraception is financially, psychologically and physically less burdensome than abortion.

Unwanted pregnancy—the global context

  1. Top of page
  2. Introduction
  3. Unwanted pregnancy—the global context
  4. What is emergency contraception?
  5. Who will use emergency contraception?
  6. Methods of emergency contraception
  7. How does emergency contraception work?
  8. Access and availability
  9. Conclusion
  10. References

Women must know that it is possible to prevent pregnancy after intercourse before they can look for treatment. Knowledge of emergency contraception is therefore crucial to its use. Global rates of unintended pregnancy are alarming and would suggest that knowledge of, and access to, emergency contraception is an area that needs to be developed. Although there are obviously variations between nations, there are approximately 50 million pregnancies terminated each year1. In the United Kingdom, over 180,000 pregnancies are terminated annually2. In Finland, the abortion rate has been quoted as 7.9/1000 for all fertile-aged women, and 9/1000 for adolescents, with a total number of 10,000 pregnancies terminated per year3. In Africa, about five million abortions take place per year4. Nigeria is the most populous country in Africa with a population of about 120 million. The maternal mortality rate is one of the highest in the world (1000 per 100,000 live births) and this seems to be on the increase5. The incidence of induced abortion is 25/1000 women of reproductive age per year. There are approximately 610,000 abortions performed in Nigeria annually, 60% of which are believed to be unsafe6. In the United States, almost 50% of pregnancies are unwanted7. Given these figures, the need for emergency contraception cannot be over-emphasised, and yet emergency contraception has been called the best-kept contraceptive secret, typically unavailable to women in developing countries8,9. There are an estimated 120 million women in developing countries who do not practice family planning. The HIV/AIDS epidemic in most developing countries has led many women to resort to condom alone while neglecting more effective methods of contraception. As condoms continue to break, split and slip off, the rate of unwanted pregnancies will remain high with unsafe abortion as a result of the illegality of the practice in most of these countries. Unintended pregnancy is a global problem, which affects women, their families and society. Abortion is a frequent consequence, but in the developing world it can result in serious long term negative effects including infertility and maternal death10. Unwanted pregnancies can also be a root cause of many social problems, including teenage pregnancy, single parenthood, failure of women to complete their education, welfare dependency and the continuation of poverty. It is also associated with failure to seek early prenatal care, substance abuse in early pregnancy, low birthweight, infant mortality and child abuse11.

What is emergency contraception?

  1. Top of page
  2. Introduction
  3. Unwanted pregnancy—the global context
  4. What is emergency contraception?
  5. Who will use emergency contraception?
  6. Methods of emergency contraception
  7. How does emergency contraception work?
  8. Access and availability
  9. Conclusion
  10. References

Emergency contraception is defined as the use of drugs or devices to prevent pregnancy within a few days of unprotected coitus7,12–14. It is sometimes referred to as ‘morning after’ or postcoital contraception7. The term emergency contraception also stresses the fact that the regimens are not intended for ongoing use. They are for postcoital employment, but before the establishment of pregnancy—a ‘back-up’ method15. Although emergency contraception was first used in the 1960s, it is a largely unknown method. A review of the scientific literature shows a widespread lack of knowledge among providers and women regarding the various methods, how to use them and where to obtain services16,17. Unintended pregnancies continue to be a major global tragedy for millions of women, but one which could be significantly reduced by emergency contraception18. About 50 million pregnancies are terminated each year14, and it has been calculated that the widespread use of emergency contraception in the United States could prevent over one million abortions, and two million unintended pregnancies that end in childbirth each year19.

The historical evolution of these regimens began in the 1920s, but the first documented use was not published until the mid-1960s20. A variety of different methods have become available since then. The first to be described was high dose oestrogen, although currently the most widely used is a combination of oestrogen and progestin. One highly effective method is the postcoital insertion of an intrauterine device, but this is often seen as less convenient14. There are also traditional methods for postcoital contraception widely practiced in some parts of the world, although with no proven efficacy. Methods include the use of herbs and plants, injections, urination after intercourse or an overdose of vitamin C, aspirin and chloroquine. Mixtures of contraceptive pills and other substances, tequila, Coca-Cola, marijuana with alcohol, vinegar or baking soda vaginal douches and sucking on lemons have been tried. Other postcoital methods include physical gyrations, such as assumption of unusual body positions and various incantations21,22.

Behind all debates about contraception are questions of what we are actually looking for—an ideal emergency contraception which should be highly effective and free of side effects. In addition to this, it should not disturb the menstrual cycle, as any delay will raise concerns in the woman about possible method failure, thus adding to her anxiety. An ideal emergency contraceptive should also be effective despite a long interval between the episode of unprotected intercourse and administration. It should preferably be a single dose, easily administered and affordable15. However, no available emergency contraceptive has all of these attributes; thus, the search for an ideal emergency contraceptive has continued and has led to recent interest in the development of alternative regimens.

Who will use emergency contraception?

  1. Top of page
  2. Introduction
  3. Unwanted pregnancy—the global context
  4. What is emergency contraception?
  5. Who will use emergency contraception?
  6. Methods of emergency contraception
  7. How does emergency contraception work?
  8. Access and availability
  9. Conclusion
  10. References

Emergency contraception can be used after unprotected intercourse by almost every woman of reproductive age who is sexually active and fertile, and who wishes to prevent unintended pregnancy17. Most of the data available on the characteristics of potential users of emergency contraception come from developed countries, but important information can still be extrapolated and applied to other situations to a certain extent. Critical cultural and social factors should also be examined in any wider research review to appreciate the entire ‘package’ of factors, which affect the decisions of both users and providers. A number of reasons have been offered for needing emergency contraception—firstly, many women have difficulties using their regular methods of contraception. Condom users may experience breakage or slippage; similarly, the diaphragm or cervical cap may move out of place. Pill users may not remember to take their tablets regularly giving rise to failure of the method. Secondly, other potential users are women who have engaged in an unexpected sexual activity either by being forced (as in cases of rape) or coerced into having unplanned, unprotected intercourse. If all women who were raped used emergency contraception, about 22,000 pregnancies resulting from rape could potentially be prevented annually in the United States23. Thirdly, it is useful for women using the withdrawal method in instances where withdrawal occurred too late, or, fourthly, for women practicing the rhythm or calendar method with any miscalculation of the ‘safe’ days for periodic abstinence24,25. Fifthly, there are some women who are using no regular method of contraception as a result of either fear of, or discomfort with, side effects, or lack of knowledge of availability26. Finally, emergency contraception is particularly suitable for adolescents because of their patterns of sexual behaviour and contraceptive use. They, unfortunately, incorrectly start sexual activity before practicing contraception. They often do not plan their first intercourse, or may have infrequent intercourse with no contraceptive protection. In addition, adolescents practicing serial monogamy may use oral contraceptives effectively during a relationship and discontinue use when it ends, thus when a new relationship begins, they may be unprepared and use no methods27.

The uptake of emergency contraception for adolescents who are the most important target group is however low.

A study of pregnant teenagers to assess the knowledge and use of emergency contraception by Pearson et al.28 in 1995 shared that knowledge of emergency contraception was as high as 81%. However, 88% of these pregnant teenagers did not obtain it. Another study by Graham et al.29 in 1996 among teenagers (14 and 15 year olds) in secondary schools to assess the knowledge of emergency contraception showed that 98% girls and 87% boys have heard of emergency contraception but only 26.4% gave the correct time limit of 72 hours. Confidentiality was also crucial in this age group, as most of the pupils would not want the doctors to tell their parents. It was also noted that schools and the media were important sources of information among this group, as they do not come into contact with health care providers often, thus, detailed and correct information must be given through these sources. Cohall et al.30, in their study to assess the awareness of emergency contraception among inner city adolescents attending a general primary health care clinic in New York city, showed that about 71% of the sample was sexually experienced and the mean age of first intercourse was 14. It was noted that only 30% of the sexually experienced had heard of emergency contraception, which was very low compared with other studies. The intent to use emergency contraception was however high as 87% of respondents said they would use emergency contraception if the need arises in the future. This indicated a strong desire among the adolescents to prevent unintended pregnancy. Eighty percent of those who had heard of mifepristone, however, were not sure of the difference between emergency contraception and abortifacient. Some adolescents may be troubled by medical abortion but reassured by a second chance to prevent pregnancy. Educational messages must distinguish clearly between emergency contraception and abortifacient. In another study among Nigerian youths in 199931, 95% of the respondents approved of the use of emergency contraception.

Methods of emergency contraception

  1. Top of page
  2. Introduction
  3. Unwanted pregnancy—the global context
  4. What is emergency contraception?
  5. Who will use emergency contraception?
  6. Methods of emergency contraception
  7. How does emergency contraception work?
  8. Access and availability
  9. Conclusion
  10. References

Combined oestrogen and progestin

First described by Yuzpe and Lancee32, this combination therapy is often referred to as the Yuzpe regimen. The oestrogen–progestin regimen consists of two doses of a combination of 100 μg of ethinyl estradiol and 0.5 mg of levonorgestrel each, the first dose taken within 72 hours of intercourse and the second dose 12 hours later33–37. This is the most commonly used emergency contraceptive. A licensed product is available in several countries in Western Europe and New Zealand. In the United Kingdom, it is marketed as Schering PC4, and as Tetragynon in Switzerland38. Commercially available brands of combined oral contraceptive pills can also be used39.

Although several other brands of combined oral contraceptive pills contain the same hormones needed for the Yuzpe method, but in lower doses, care must be taken to ensure that women using such brands take a greater number of pills, for example, two tablets of Ovral per dose, while four tablets of Nordette, Levlon, Levora, Lo/Ovral, Triphasil, Tri-Levlen and Trivora per dose40,41. More research is needed to ascertain the effectiveness of the oestrogen–progestin regimen if taken more than 72 hours after intercourse. By comparing observed and expected pregnancies, efficacy studies have demonstrated that the Yuzpe method reduces the chances of pregnancy by about 75%42.

The common side effects associated with this regimen are nausea and vomiting of which up to 50% and 20%, respectively, have been reported43. This may occasionally interfere with taking the second dose and vomiting may reduce efficacy if it occurs less than 2 hours after taking the medication. Some clinics give routine anti-emetic medication. Other side effects include headaches, breast tenderness (mastalgia), abdominal pain and dizziness. The subsequent period is usually on time but can be a little earlier or later, and may be rather heavy12. There are no absolute contraindications to the use of the oestrogen–progestin regimen except known pregnancy. There is also no evidence linking its use to the risk of fetal malformation14,20,44.

Oestrogen alone

During the 1960s and early 1970s, high dose oestrogen was the standard regimen20. This method is sometimes referred to as the ‘five by five’ regimen, and consists of five tablets of 1 mg ethinyl estradiol given daily for five days7,14. It is said to be as effective as the Yuzpe method but produces more side effects. The nausea and vomiting experienced with the Yuzpe regimen are exaggerated with the oestrogen-only regimen and more women experience these side effects. Additionally with the high dose of oestrogen sustained for five days, there is a theoretically higher risk of thromboembolism. Most clinicians stopped using oestrogen alone when the oestrogen–progestin regimen was prescribed, although it is still in use in the Netherlands7,45,46.

Progestin alone

The levonorgestrel regimen consists of two doses of 0.75 mg of levonorgestrel taken 12 hours apart starting within 48 hours of unprotected intercourse35. A recent randomised controlled trial by the WHO has shown that the levonorgestrel regimen is better tolerated and more effective than the Yuzpe regimen47.

A levonorgestrel-only product (Postinor) is available from pharmacists in parts of Eastern Europe, the Far East and many developing countries14,20. In the United Kingdom, there is no licensed levonorgestrel-only product48. The progestin-only pill distributed in the United States, the Ovrette brand, contains 0.075 mg of dl-norgestrel per tablet, therefore a total of 40 tablets is needed to make up the complete regimen for emergency contraception7. A progestin-only product was launched in May 1999 in France and is likely to follow suit in the UK, a preferred method of choice as a result of reduced side effects.

The intrauterine contraceptive device

The copper-bearing intrauterine device is a highly effective postcoital contraceptive with failure rates of less than 1%49,50. It is used for up to five to seven days after unprotected intercourse and is particularly appropriate for women who wish to use the device as a long term method of contraception. The service delivery challenge raised by this method is the fact that a trained health care provider under aseptic conditions must insert it. In addition, the method is contraindicated for women at risk of sexually transmitted diseases who are frequently the same women who need emergency contraception. It may be difficult to insert in nulliparous women20. It is therefore proper to screen women for infection, or to give an antibiotic before insertion of the device51.

Danazol

This is a synthetic progestin and androgen. It is an anti-gonadotrophin, which could be used as an emergency contraceptive. The danazol regimen consists of 400 mg each taken 12 hours apart with the first dose given within 72 hours after unprotected intercourse. Other variants of this regimen involve three doses of 400 mg each, taken 12 hours apart, and two doses of 600 mg taken 12 hours14,20. Investigations on the danazol regimen have shown that the two most thorough trials have conflicting results. One trial concluded that the method is effective52, while the randomised study in the United Kingdom suggested that danazol may be ineffective when used after intercourse34. The advantages of danazol are that its side effects are less prevalent and less severe than those associated with the Yuzpe method. Another advantage is the fact that danazol can be taken by women with contraindications to combined oral contraceptives or oestrogen20. The disadvantage is that danazol is expensive and not readily available, which makes it unsuitable for emergengy contraception.

Anti-progestins

Mifepristone is a synthetic steroid with potent anti-progestational and anti-glucocorticoid properties that provides an effective medical method of inducing abortion in early pregnancy43. Preliminary trials have shown that the drug is highly effective as an emergency contraceptive34,43. Mifepristone is known to inhibit implantation as well as ovulation. The regimen for emergency contraception consists of a single dose of 600 mg of mifepristone given within 72 hours of unprotected intercourse. All the side effects noticed with the other methods were much less common among the women given mifepristone, except for the delay in the onset of next menses14,20.

The WHO, in its multicentre randomised trial to assess the safety and effectiveness of lower doses of mifepristone (50 and 10 mg) and a longer postcoital treatment period (120 hours), has recently revealed that lowering the dose of mifepristone did not decrease its effectiveness as an emergency contraceptive and lower doses were associated with less disturbance of the menstrual cycle53. These lower doses might probably be more acceptable politically in countries where abortion is illegal compared with the high doses used as an abortifacient.

How does emergency contraception work?

  1. Top of page
  2. Introduction
  3. Unwanted pregnancy—the global context
  4. What is emergency contraception?
  5. Who will use emergency contraception?
  6. Methods of emergency contraception
  7. How does emergency contraception work?
  8. Access and availability
  9. Conclusion
  10. References

The mode of action of emergency contraception is not only clinically important—for many users, the way in which it works can affect the acceptability of use. In a recent review of literature by Croxatto et al.54 on the mechanism of action of hormonal preparations used for emergency contraception, it is evident that further research to fully determine the mode of action is needed to bridge the gap of information that hinders a clearcut answer to the mechanism by which emergency contraception prevents pregnancy. Although the exact mechanisms of action have not been identified, it is clear that the method prevents pregnancy from starting. This is evident by the fact that emergency contraceptive pills do not cause abortions and are ineffective if a woman is already pregnant. All emergency contraceptives currently in use act before implantation7,15. Recent studies done on the mechanisms of action show that emergency contraceptive pills may prevent or delay ovulation. They may also disrupt the luteal phase of the cycle, thus interfering with fertilisation, or may interfere with implantation by altering the lining of the womb so that a fertilised egg is less likely to implant. They may also alter the activity of the fallopian tube so that the egg and sperm are less likely to meet14. There is a lack of evidence regarding the efficacy of emergency contraception, partially—and obviously—because of ethical issues. There have never been any placebo-controlled trials of emergency contraception and it is difficult to quantify effectiveness. Most studies include large numbers of young women with no proven fertility while others simply report failure rates in terms of the number of pregnancies among the treated women. More recently, attempts have been made to estimate the number of women genuinely at risk of pregnancy (i.e. those who had unprotected intercourse during the fertile period), and to compare observed and expected pregnancies. There can be side effects—about half of women who take emergency contraceptive pills experience nausea and another fifth may vomit during the hours following treatment with certain regimens. Other side effects can include mastalgia, headaches, dizziness and abdominal pain, and there may be disturbances in the menstrual cycle with the next period being a little earlier or later, and it may be rather heavy. Serious illness leading to hospital investigation or admission has not been reported.

Access and availability

  1. Top of page
  2. Introduction
  3. Unwanted pregnancy—the global context
  4. What is emergency contraception?
  5. Who will use emergency contraception?
  6. Methods of emergency contraception
  7. How does emergency contraception work?
  8. Access and availability
  9. Conclusion
  10. References

The availability of emergency contraception differs widely from one country to the other. It is most widely used in Europe while still perceived to be something of a new method in many other countries7,55,56. The wide variability in the use of emergency contraception could be due to the fact that, as a licensed product, it is only available in some areas. In others, equivalent regimens of hormonal oral contraceptive pills are utilised while in the remainder countries nothing at all is used. Women in many European countries have had access to dedicated emergency contraceptive products for a number of years. Camp55 has outlined the products available, but generally, emergency contraception is accessible in the UK, Denmark, Germany, Finland, Norway, Switzerland, Sweden, South Africa and most Eastern and central European countries7. It also exists in some developing countries including Nigeria, Pakistan and Thailand. The first United States dedicated emergency contraceptive product became available in 199857. A new product, which consists of a two-tablet package for one-time emergency contraception use, is on trial in Kenya, Indonesia and Sri Lanka55. In Australia, emergency contraceptive pills are widely available and use is fairly high. In New Zealand, use is well established and regulations were recently changed to make the method available without prescription. In Asia and Latin America, there is not much breakthrough, and in Malaysia, there has been some confusion about the mechanism of action (in addition to this, the method is viewed as an abortifacient, thus providers are reluctant to speak about it). The call for greater accessibility to emergency contraception has led to debates as to whether the pills should continue to be available by prescription only58. In most countries, emergency contraception is only available with a doctor's prescription, while a few places have now involved pharmacies to expand access59. Overmedicalisation of the consultation for emergency contraception could be a constraint to easy accessibility. Unnecessary use of pregnancy test, pelvic examination, consent forms and medical visits can limit access to emergency contraception25,60. There has also been discussion as to whether emergency contraception should be available over the counter25. Other arguments associated with wider access are that women might become less careful with their ongoing contraceptive methods and easier access may encourage people to have unprotected sex. There is no evidence to suggest that couples are more likely to have unprotected sex when they know the woman can use emergency contraception. Reported evidence suggests that making emergency contraceptive pills more widely available does not increase risk taking and may actually reduce the incidence of unintended pregnancy61–65. Unfortunately, there are no figures available as to how many people use emergency contraception in any country. The only ‘guesstimates’ are based on the number of pill packs sold3. Studies done on emergency contraception, however, point to the fact that this method of contraception is not widely known and is under-utilised66–71. Poor knowledge, even among providers, was evidenced by the lack of confidence in prescribing emergency contraception, the lack of routine dissemination of information and the restricted time limit to 24–48 hours in some studies57,72–74. This could limit access to emergency contraception. A consumer survey in the United Kingdom, where use of emergency contraception is thought to be the highest in the world, suggests that around 12% of women have ever used emergency contraception75.

Conclusion

  1. Top of page
  2. Introduction
  3. Unwanted pregnancy—the global context
  4. What is emergency contraception?
  5. Who will use emergency contraception?
  6. Methods of emergency contraception
  7. How does emergency contraception work?
  8. Access and availability
  9. Conclusion
  10. References

For prospective users, some conclusions can be reached and guidelines given. The intrauterine device—although highly effective—requires a ‘surgical procedure’ before it can be used. The combined oestrogen–progestin method is the most widely available, although levonogestrel alone is likely to replace it in the near future because of better tolerability and possibly better efficacy. Mifepristone, already widely used in China, looks very promising and needs to be explored.

From the figures stated previously, it is observed that the rate of unintended pregnancy and the frequent consequence of abortion are unacceptable and too high. Easy availability and accessibility of emergency contraception with improved knowledge will go a long way toward preventing most of these unwanted pregnancies. The new interest in emergency contraception should, one hopes, lead to myths and misunderstandings being dispelled. Providers will become better informed and more aware and may start, proactively, to inform their patients.

References

  1. Top of page
  2. Introduction
  3. Unwanted pregnancy—the global context
  4. What is emergency contraception?
  5. Who will use emergency contraception?
  6. Methods of emergency contraception
  7. How does emergency contraception work?
  8. Access and availability
  9. Conclusion
  10. References
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