Utmj vol 80 no 3 inside

Emergency Contraception: The Canadian Perspective
Alana Flexman, B.Sc. (0T4)Shannon Wires, M.Sc. (0T5) Abstract
under-utilised due to a general lack of awareness about its avail- Emergency Contraception (EC) is defined by the Society of
ability and difficulty in accessing EC within the appropriate time Obstetricians and Gynecologists of Canada (SOGC)
frame.4 As a result, a recent University of Toronto study estab- Guidelines as any method of contraception that is used after
lished a pilot project for pharmacy access to EC and has identi- intercourse and before implantation. Two methods of EC
fied a pressing need for improved access to EC.5 are accessible in Canada: hormonal medications and the
postcoital intra-uterine device (IUD). The hormonal EC
Emergency Contraceptive Options
methods commercially available in Canada are Preven®
The accepted methods for emergency contraception available in (combined ethinyl estradiol and levonorgestrel) and Plan B®
Canada consist of two hormonal methods and the insertion of a (levonorgestrel alone). Emergency contraception has been
postcoital intrauterine contraceptive device (IUD). The most shown in the research literature to have high efficacy in pre-
widely used method in Canada is the Yuzpe Method.2 This hor- venting pregnancy when used within 72 hours of unprotect-
monal method was first described in 1977 and involves a combi- ed intercourse. The hormonal methods are well tolerated
nation of 100 micrograms of ethinyl estradiol and 500 mg of lev- with minimal side effects, and are not teratogenic to an
onorgestrel taken in two doses 12 hours apart.2 The first dose established pregnancy. Given its simplicity of use and the
should be initiated within 72 hours of unprotected intercourse.
need for timely administration, several other countries and
Several oral contraceptive pills can be used to achieve this dose if two Canadian provinces, British Columbia and Québec, have
needed, although none is approved specifically for this use (Table begun to offer EC without a prescription from pharmacists.
1). Preven®, a product containing the hormonal combination of Moreover, a recent study from the University of Toronto has
the Yuzpe regimen in a single pill, was approved for use in Canada piloted this concept in the Toronto area with encouraging
in 1999 by prescription specifically for use as emergency contra- results. In conclusion, the future of emergency contracep-
ception. A second hormonal method, Plan B®, has also been tion in Canada is evolving towards improved, timely access
available in Canada since February 2000. This method uses 750 for all women thus resulting in a probable reduction in
mg of levonorgestrel alone taken in two doses 12 hours apart.
unwanted pregnancies.
The postcoital copper IUD can be used past the 72-hour window Introduction
following intercourse,6 as it is effective up to 7 days after inter- Every year, hundreds of thousands of Canadian women are at risk course. It is the most effective postcoital contraception as the fail- for unintended pregnancy as a result of unprotected intercourse, ure rate does not exceed 0.1%.7 This method is most appropriate inadequate contraceptive measures or failure of contraceptive for women who meet the regular criteria for use of an IUD, as methods. The use of emergency contraception is defined in the the IUD can stay in place for long term contraception following Society of Obstetricians and Gynecologists of Canada (SOGC) insertion.20 There is currently no evidence to recommend the lev- Guidelines as “any method of contraception which is used after onorgestrel-releasing intrauterine system, marketed under the trade intercourse and before implantation,”1 and has the potential to pre- name Mirena®, for emergency contraception. vent many of these unwanted pregnancies. It has been knownsince 1977 that a high dose of oral contraceptive (norgestrel-ethinyl In large randomised control trial of women in 1998, the crude estradiol) within 72 hours of having unprotected intercourse will pregnancy rate for levonorgestrel (Plan B®) was 1.1%, compared significantly reduce a woman’s chance of becoming pregnant.2 to 3.2% for the Yuzpe regimen8 and 0.1% for the postcoital IUD.7 Nevertheless, commercially packaged emergency contraception In terms of the proportion of pregnancies prevented compared (EC) has become available only recently in North America, despite with the expected number without treatment, the levonorgestrel growing evidence about its safety and efficacy.3 Moreover, EC is method prevented 85% of possible pregnancies and the Yuzpe regimen 57% of possible pregnancies in this study. The efficacy there are several ways in which this method may provide contra- of both treatments decreased with delay from the event of unpro- ception. For example, when given prior to ovulation, the hor- tected intercourse. In other studies, however, the Yuzpe regimen mones will inhibit ovulation in some women.14-15 Other studies has been attributed efficacies as high as 75 percent.9 With such have suggested a mechanism of impaired implantation of the high efficacy, EC is thus able to reduce the number of therapeu- embryo due reduced endometrial receptivity, as histologic or bio- tic abortions needed due to unplanned pregnancy.
chemical alterations in the endometrium were observed followingEC administration.16-18 Conversely, some studies have found no Mifepristone (RU-486), an anti-progestin, is also highly effective as such effect on the endometrium,19-20 thus the exact mechanism emergency contraception but is currently unavailable in Canada.
remains unclear. Other possible mechanisms suggested in the lit- Several randomized, controlled trials have shown that a single oral erature include changes to the cervical mucus and subsequent 600 mg dose of mifepristone was more effective and had less changes in the transport of sperm, egg or embryo,21 and impair- adverse effects than the Yuzpe Method.10 Further studies have shown the efficacy of a 10 mg, 200 mg and 600 mg dose ofmifepristone was similar.10 No major side effects occurred, how- The mechanism of action of the postcoital IUD is also poorly ever the delay in return of menstruation was dose-dependent and understood; however it is theorised that the IUD affects tubal thus the dose of 10 mg is most desirable. Despite its high effica- transport of an oocyte or embryo, changes the cervical mucus and cy and favourable profile, Mifepristone is not currently available in Canada and is unlikely to be in the near future.3 Indications and Contraindications
According to the SOGC Guidelines (2000), the indications for
emergency hormonal contraception, are the desire to prevent preg- Emergency Contraceptive Doses of Dedicated Emergency
nancy and unprotected intercourse 72 hours prior to seeking med- Contraceptives vs. Combination Oral Contraceptive Pills
ical advice.1 Emergency contraception is also considered in cir-cumstances of high pregnancy risk that result from failure ofexisting contraception, such as barrier methods or missed birth control pills.1 There is some evidence that the effectiveness of ECmay last longer than the recommended 72 hour period, with a reported 72-87% efficacy 72 to 120 hours after intercourse.24 As well, based on current literature on efficacy, SOGC recommenda- tions are that a postcoital IUD be considered for women at riskof pregnancy 3-7 days after unprotected intercourse.1 Hormonal EC is not recommended as a primary form of contraception and should be used only in emergency situations.1 However, multiple use of EC has no known health risks and there are no con- Emergency contraception is extremely safe: no deaths have beenassociated with EC use and there is no causal association betweenEC and the small number of reported adverse effects.13 There are * Ethinyl estradiol ** Levonorgestrel no absolute contraindications to the use of emergency hormonalcontraception, with the exception of pregnancy due to their inef- From: SOGC guidelines “Emergency Contraception” July 2000 fectiveness. As stated previously, there is no evidence of terato-genic consequences to the fetus since EC will not alter an estab-lished pregnancy and is of no utility in this situation.25 The World Mechanism of Action
Health Organization Guidelines indicate that breast-feeding and a Emergency contraception is known to prevent pregnancy before it history of ectopic pregnancy should not restrict access to hor- occurs. Thus, the mechanism of action is fundamentally different monal EC.26 Furthermore, in women with a history of severe car- from the interruption of an established pregnancy. The implanta- diovascular complications, angina pectoris, migraine or severe liver tion process is prevented which occurs six to seven days after fer- disease, the benefits of EC generally outweigh the potential risks tilization.7 Studies of high-dose oral contraceptive pills have shown of pregnancy. Neither smoking nor age is considered a con- that the combined estrogen-progestin regimen (Yuzpe Method, traindication. Athough some physicians are cautious about the use Preven®) and the progestin-only regimen (Plan B®) will not inter- of estrogen-based EC in women with clotting disorders, migraine, or hormone sensitive tumours, the short-term contraceptive bene-fit of estrogen exceeds the risk of treatment when one considers Multiple theories have been proposed to explain the high efficacy the adverse outcomes of pregnancy in the same population.13 of hormonal methods of emergency postcoital contraception.13Depending on the timing of administration in the menstrual cycle, Contraindications to the use of a postcoital IUD are identical to those for normal contraceptive use, such as pelvic infections and Surgeons of Canada, the Canadian Nurses Association, the (acute, recent or recurrent), pregnancy or a distorted uterine cavi- Canadian Pediatrics Society, and six provincial medical colleges.4 ty.20 Although postcoital IUD has high efficacy and few con- Furthermore, a cost analysis of use of EC in Canada showed that traindications, it is not commonly administered by physicians due EC was cost-saving whether provided at the time of the emer- to the concern regarding the risk of pelvic inflammatory disease gency or in advance to be used as needed.35 and the time required to administer the device.20 In December 2000, British Columbian Premier Ujjal Dosanjh Side Effects
approved the availability of EC directly from pharmacists without The primary side-effects of hormonal EC are nausea and vomit- a prescription.36 In the first 8 weeks, 800 women accessed EC ing.25 The Yuzpe regimen causes nausea in up to 50% of patients from pharmacists and over half these women obtained EC on and up to 19% experienced vomiting.8 The Levonorgestrel regi- evenings or weekends when a physician is usually unavailable.36 men (Plan B®) is better tolerated with 23% experiencing nausea The next year, the province of Quebec made EC available from and 6% experiencing vomiting.8 Nausea and vomiting can be min- pharmacists, but required a $30.00 consultation fee for this ser- imised by taking the medications with food and using anti-emetics vice.37 In June 2001, a University of Toronto pilot study headed such as dimenhydrinate (Gravol®) 30 minutes prior to the dose.1 by Sheila Dunn (Professor of Medicine) and Thomas Brown If vomiting occurs within one hour, a replacement dose is (Professor of Pharmacy) was undertaken to train pharmacists in 40 required.1 Less common side effects with both regimens include pharmacies in the Scarborough, Rexdale and North York areas to uterine cramping, spotting, headaches and bloating.1 Most women dispense EC directly to women without a prescription.
start their menstrual period on time or slightly early.23 Post coital Preliminary results indicate that close to 7000 women obtained EC IUD is associated with complications that include bleeding, infec- from these pharmacies over a one year period, 65% of whom indi- tion, perforation, cramping and expulsion.1 cated that they needed EC due to failure of their regular contra-ception and 84% indicated that it was significantly easier to get EC Follow-Up
Follow-up after EC includes a pregnancy test if menstrual bleed-ing does not occur by the 21st day following EC administration.1 A recent journal article reported that Canada is lagging behind In addition, arrangements for continued contraception and sexual- other countries in the availability of EC without a prescription.31 ly transmitted infections (STI) testing should be done 1-2 weeks Women in the United Kingdom, Morocco, Norway, Sweden, Finland, Israel, France, Belgium, Denmark, Portugal, South Africa,and Albania can already obtain EC without a prescription.31 Future Directions: Switch to Over The Counter Status?
Furthermore, a large supermarket chain in England has established Emergency Contraception is a safe medication with only one con- a pilot program to dispense EC to teenagers free of charge in traindication (pregnancy) and a relatively simple method of admin- order to address an alarming rate of teenage pregnancy.38 In con- istration. Two recent studies in France and the United States trast, EC is only available without a prescription in three American found that women had little difficulty understanding how to use states (Washington, Alaska, and California), despite the fact that EC safely and effectively without a physician’s assistance.27-28 EC is estimated to prevent 1.5 million unintended pregnancies and Furthermore, large randomised trails have demonstrated that hor- monal EC is more effective when used quickly, and the time delayin obtaining a prescription may lead to increased numbers of Conclusions
unwanted pregnancy due to decreased efficacy.29-30 The availabili- Emergency Contraception is a safe, highly effective way to prevent ty of EC without a prescription removes the clinical opportunity pregnancy in the event of unprotected intercourse or failure of reg- for physicians to provide STD and contraception counselling.
ular contraceptive methods. Their effectiveness is highly depen- While this is true, the efficacy of this counselling has not been dent on their time of administration following unprotected inter- demonstrated.31 In addition, some might argue that physicians course; therefore over-the-counter availability has been proposed should identify the woman’s pregnancy status prior to EC admin- and widely supported by many medical organisations. Pharmacists istration and discuss side effects. However, since there is no risk are the most easily accessed, qualified health professionals for the to the pregnancy and the side effects are uncomplicated, this infor- distribution of EC in a timely manner. Several nations and select mation could readily be communicated by a pharmacist.11 Canadian provinces have explored options in distribution of EC Furthermore, some supporters of EC regulation argue that without a prescription with highly successful results. As Canada increased EC availability will lead to its use as a regular contra- heads towards easier, more convenient access to emergency con- ceptive, rather than an emergency medication.29 traception, it is with clear benefit to the reproductive health of numerous studies have indicated that advance provision of EC for women at risk of unintended pregnancy does not replace tradi-tional contraception.32-34 References
1.
Davis, V, Dunn S. (2000). SOGC Clinical Practice Guidelines: EmergencyPostcoital Contraception, SOGC Journal, No. 92. The SOGC initiated a campaign to increase awareness and avail- Yuzpe AA, Lancee WJ. (1977). Ethinylestradiol and dl-norgestrel as a postcoitalcontraceptive. Fertil Steril. 28: 932-936.
ability of EC in 1998.4 Other Canadian supporters include the Weir E. (2001). Emergency contraception: a matter of dedication and access.
Canadian Pharmacists Association, the Royal College of Physicians Sibbald B. (2001). Emergency Contraceptive Pill hits Ontario Market. CMAJ.
22. Ling WY, Wrizon W, Acorn T, et al. (1983). Mode of action of dl-norgestrel and ethinylestradiol combination in postcoital contraception. III. Effects of preovula- Wong, J. (2002). Women need wider access to emergency contraception: study.
tory administration following the luteinizing hormone surge on ovarian steroidoge- News @ U of T. Retrieved Dec. 22, 2002 from World Wide Web: nesis. Feril Steril. 40: 631-636.
http://www.newsandevents.utoronto.ca.
23. Thomas M. (2001). Postcoital Contraception. Clin Ob Gyn. 44(1): 101-105.
Lippes J, Malik T, Tatum HJ. (1976). The postcoital copper-T. Adv Plann Parent.
24. Rodrigues I, Grouf F, Joly J. (2001). Effectiveness of Emergency Contraceptive Pills between 72 and 120 hours after unprotected sexual intercourse. Am J Obs Trussell J, Ellertson C. (1995). Efficacy of emergency contraception. Fertil Contr 25. Bracken MB. (1990). Oral Contraception and Congenital Malformations in Off- Task force on Post Ovulatory Methods of Fertility Regulation. (1998).
spring: A review and meta-analysis of prospective studies. Obstet Gynecol. 76: 552- Randomised control trial of levonorgestrel versus the Yuzpe regimen of Combined Oral Contraceptions for Emergency Contraception. Lancet. 352: 428-433.
26. World Health Organization. (2000). Improved access to quality care in family Trussell, J, Rodriquez, G, Ellertson, C. (1999). Updated estimates of the effec- planning: Medical eligibility criteria for contraceptive use, 2nd ed. Geneva: Reproductive tiveness of the Yuzpe Regimen of emergency contraception. Contraception. 59: 27. Raymond EG, Dalbout SM, Camp SI. (2002). Comprehension of a Prototype 10. Glasier A, Thong KJ, Dewar M, et al. (1992). Mifepristone (RU 486) compared Over the Counter Label for an Emergency Contraception Pill Product. Obstet with high-dose estrogen and progestogen for emergency post-coital contraception.
N Engl J Med. 327: 1041-1044.
28. Aubeny E. (2000). Can Hormonal Emergency Contraception (EC) be Available 11. Grimes DA. (1997) Emergency contraception-expanding opportunities for prima- without Medical Prescription. Eur J Contracept Reprod Health Care. 5: Suppl 1: 41.
ry prevention [editorial]. N Engl J Med. 337: 1078-9.
29. Piaggio G, Von Hertzen H, Grimes DA, Van Look PF. (1999). Timing of 12. Raman-Wilms L, Tseng AL, Wighardt S, et al. (1995). Fetal genital effects of first- Emergency Contraception with Levonorgestrel or the Yuzpe regimen. Lancet. 353: trimester sex hormone exposure: a meta-analysis. Obstet Gynecol. 85: 141-149.
13. Grimes DA. Raymond EG. (2002). Emergency contraception. Ann Int Med.
30. Trussell J, Duran V, Shochet T and Moore K. (2000). Access to Emergency Contraception. Obstet Gynecol. 95:267-270.
14. Landgren BM, Johannisson E, Aedo AR, et al. (1989). The effect of levonorgestrel 31. Grimes D. (2002). Switching Emergency Contraception to Over the Counter administered in large doses at different stages of the cycle on ovarian function and endometrial morphology. Contraception. 39: 275-289.
32. Glasier A, Baird D. (1998). The Effects of Self-Administering Emergency 15. Hapangama D, Glasier AF, Baird DT. (2001) The effects of peri-ovulatory admin- Contraception. N Engl J Med 339: 124.
istration of levonorgestrel on the menstrual cycle. Contraception. 63: 123-129.
33. Raine T, Harper C, Leon K, Darney P. (2000). Emergency Contraception: 16. Ling WY, Robichaud A, Zayid I, et al. (1979). Mode of action of DL-norgestrel Advance Provision in a young high risk clinic population. Obstet Gynecol. 96:127.
and ethinylestradiol combination in postcoital contraception. Fertil Steril. 32: 297- 34. Ellertson C, Ambardekar S, Headley A, et al. (2001). Emergency contraception: Randomised Comparison of Advance Provision and Information Only. Obstet 17. Kubba AA, White JO, Guillebaud J, Elder MG. (1986). The biochemistry of human endometrium after two regimens of postcoital contraception: a dl- 35. Trussell J, Wiebe E, Shochet T, Guilbert E. (2001). Cost Savings from Emergency norgestrel/ethinylestradiol combination or danazol. Fertil Steril. 45(4):512-516.
Contraceptive Pills in Canada. Obstet Gynecol. 97 (5): 789-793.
18. Ling WY, Wrixon W, Zayid I, et al. (1983). Mode of action of dl-norgestrel and 36. BC Pharmacy Association Newsletter, Dec-Jan 2002.
ethinylestradiol combination in postcoital contraception. II. Effect of postovulato- 37. Canadian Press. ( Dec. 20, 2001). Quebec Pharmacists May Now Dispense ry administration on ovarian function and endometrium. Fertil Steril. 39: 292-297.
Emergency Contraception Without A Prescription. Retrieved Dec. 22, 2002 from 19. Swahn ML, Westlund P, Johannisson E, Bygdeman M. (1996). Effect of post- World Wide Web: http://www.kaisernetwork.org/daily_reports/rep_ coital contraceptive methods on the endometrium and the menstrual cycle. Acta Obstet Gynecol Scand. 75: 738-44.
38. New York Times. (March 18,2002). Great Britian’s Largest Supermarket Chain 20. Raymond, Eg, Lovely LP, Chen-Mok M, et al. (2000). Effect of the Yuzpe regi- Dispenses Free Emergency Contraception to Minors in a Pilot Project. Retrieved men of emergency contraception on markers of endometrial receptivity. Hum Dec. 22, 2002 from World Wide Web: http://www.kaisernetwork.org/ daily_reports/rep_index.cfm?hint=2&DR_ID=10082 21. Kesserii E, Camacho-Ortega P, Laudahn G, Schopflin G. (1975). In vitro action 39. Weiss B. (2001). OTC Emergency Contraception? RN. 64(5): 3-5.
of progestogens on sperm migration in human cervical mucus. Fertil Steril. 26:57-61.
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