Doi:10.1016/j.ajog.2004.01.063

American Journal of Obstetrics and Gynecology (2004) 190, S30e8 James Trussell, PhD,a,* Charlotte Ellertson, PhD,b Felicia Stewart, MD,cElizabeth G. Raymond, MD, MPH,d Tara Shochet, MPHe Woodrow Wilson School of Public and International Affairs, Office of Population Research, Princeton University,Princeton, NJa; Ibis Reproductive Health, Cambridge, Massb; University of California San Francisco, Center forReproductive Health Research & Policy, San Francisco, Calif c; Biomedical Affairs Division, Family HealthInternational, Research Triangle Park, NCd; Population Studies Center, University of Michigan, Ann Arbor, Miche Received for publication September 11, 2003; accepted January 27, 2004 –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– Emergency contraception is an underused therapeutic option for women in the event of unpro- tected sexual intercourse. Available postcoital contraceptives include emergency contraceptive pills (ECPs) both with and without estrogen, and copper-bearing intrauterine devices. Each method has its individual efficacy, safety, and side effect profile. Most patients will experience pre-vention of pregnancy, providing they follow the treatment regimen carefully. There are concernsthat women who use ECPs may become lax with their regular birth control methods; however,reported evidence indicates that making ECPs more readily available would ultimately reducethe incidence of unintended pregnancies. In addition, it is typically conscientious contraceptiveusers who are most likely to seek emergency treatment. Patient education is paramount in the re-duction of unintended pregnancies and there are numerous medical resources available to womento assist them in this endeavor. Finally, ECPs are associated with financial and psychologic ad-vantages that benefit both the individual patient and society at large.
Ó 2004 Elsevier Inc. All rights reserved.
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– Half of all pregnancies in the United States are unin- by providing a bridge to use of an ongoing contraceptive tended; there were 3.0 million in 1994 alone, the last year method. Although emergency contraceptives do not for which data are available.Emergency contraception, protect against sexually transmitted infection, they do which prevents pregnancy after unprotected sexual in- offer reassurance to the 7.9 million women who rely on tercourse, has the potential to reduce significantly the in- condoms for protection against pregnancyin case of con- cidence of unintended pregnancy and the consequent dom slippage or breakage. Emergency contraceptives need for abortion.Emergency contraception is espe- available in the United States include combined oral con- cially important for outreach to the 3.1 million women traceptive tablets, levonorgestrel-only contraceptive tab- at risk of pregnancy but not using a regular method lets, and the copper-T intrauterine device (IUD).
The authors have no personal financial interest whatsoever in the commercial success or failure of emergency contraception.
This article is part of a supplement sponsored by Ortho-McNeil Combined emergency contraceptive pills (ECPs) are ordinary birth control pills containing the hormones * Reprint requests: James Trussell, PhD, Princeton University, estrogen and progestin. Although this therapy is com- Office of Population Research, 21 Prospect Ave, Princeton, NJ 08544.
monly known as the morning-after pill, the term is 0002-9378/$ - see front matter Ó 2004 Elsevier Inc. All rights reserved.
doi:10.1016/j.ajog.2004.01.063 Twenty-one OCs that can be used for emergency contraception in the United States* * Plan-B and Preven are the only dedicated products specifically marketed for emergency contraception. Ovral, Ogestrel, Alesse, Levlite, Aviane, Lessina, Nordette, Levlen, Levora, Portia, Seasonale, Lo/Ovral, Low-Ogestrel, Cryselle, Triphasil, Tri-Levlen, Trivora, and Enpresse have been declared safeand effective for use as ECPs by the US Food and Drug Administration.26 Outside the United States, more than 20 emergency contraceptive products arespecifically packages, labeled, and marketed. For example, Gedeon Richter and HRA Pharma are marketing in many countries the levonorgestrel-onlyproducts Postionor-2 and Norlevo, respectively, each consisting of a 2-pill strip with each pill containing 0.75 mg levonorgestrel. Norlevo becameavailable OTC without a prescription in Norway in October 2000 and in Sweden in late 2001.
y The treatment schedule is 1 dose within 120 hours after unprotected intercourse, and another dose 12 hours later. However, recent research has found that both doses of Plan B or Ovrette can be taken at the same time.
z The progestin in Ovral, Ogestrel, Lo/Ovral, Low-Ogestrel, Cryselle, and Ovrette is norgestrel, which contains 2 isomers, only 1 of which (levonorgestrel) is bioactive; the amount of norgestrel in each tablet is twice the amount of levonorgestrel.
misleading; ECPs may be initiated sooner than the morn- that 25% of women using ECPs will become pregnant.
ing afterdimmediately after unprotected intercoursedor Rather, if 100 women had unprotected intercourse once laterdfor at least 72 hours after unprotected intercourse.
during the second or third week of their cycle, about 8 The hormones that have been studied exclusively in clini- would become pregnant; after treatment with ECPs, only cal trials of ECPs are the estrogen ethinyl estradiol and the 2 would become pregnant, a 75% reduction. The cur- progestin levonorgestrel or norgestrel (which contains 2 rent treatment schedule is 1 dose within 72 hours after isomers, only 1 of whichdlevonorgestreldis bioactive).
unprotected intercourse, and a second dose 12 hours These are found in 18 brands of combined oral contracep- after the first dose. A large study by the World Health tives available in the United States as well as in 1 specially Organization (WHO) found that effectiveness declined packaged ECP product (This combination of significantly with increasing delay between unprotected active ingredients used in this way is also sometimes called intercourse and the initiation of treatThis the Yuzpe method, after the Canadian physician who first finding suggests that ECPs should be taken as soon after described the regimen. Newer research has investigated unprotected intercourse as is practical. When taking the the safety and efficacy of formulations containing ethinyl second dose 12 hours later would be difficult, however, estradiol and the progestin norethindrone; results indi- the timing of the second dose might be altered; for ex- cate efficacy, but probably less than the Yuzpe or levonor- ample, a woman who took her first dose at 3 PM imme- gestrel-only regimens (described later).
diately after discovery of a burst condom might delaytaking the second dose until 7 AM. The goal should be to make the therapy as user-friendly as possiblNew research does indicate, however, that the second The use of combined ECPs reduces the risk of preg- dose appears to increase efficacy of the therapy and so nancy by about 75%.This statement does not mean It is biologically implausible that efficacy would There have been no conclusive studies of births to abruptly plummet to zero after 72 hourMoreover, women who were already pregnant when they took new research directly investigating the effectiveness combined ECPs or after failure of combined ECPs.
beyond 72 hours suggests that combined ECPs are just However, 2 observations provide reassurance for any as effective when taken 73 to 120 hours after unprotected concern about birth First, in the event of treat- intercourse as when taken in the first 72 hour ment failure, ECPs are taken long before organogenesis Therefore, clinical protocols that deny treatment beyond starts so they should not have a teratogenic effect. Sec- 72 hours seem excessively restrictive, particularly if the ond, studies that have examined births to women who alternative of emergency insertion of a copper IUD is inadvertently continued to take combined oral con- not immediately available or appropriate.
traceptives (including high-dose formulations) withoutknowing they were pregnant have found no increased risk of birth defects.The FDA removed warningsabout adverse effects of combined oral contraceptives on About 50% of women who take combined ECPs expe- the fetus from the package insert several years ago.
rience nausea and 20% vomitIf vomiting occurs within2 hours after taking a dose, some clinicians recommend re- peating that dose. The results of one study suggest thatECPs containing levonorgestrel have an incidence of side Several clinical studies have shown that combined ECPs effects substantially lower than do ECPs containing nor- can inhibit or delay ovulation.This is an important gestrel(see last column in for information on pro- mechanism of action and may explain ECP effectiveness gestins in ECPs). The nonprescription antinausea medicine when used during the first half of the menstrual cycle, meclizine has been demonstrated to reduce the risk of nau- before ovulation has occurred. Some studies have shown sea by 27% and vomiting by 64% when two 25-mg tablets histologic or biochemical alterations in the endometrium are taken 1 hour before combined ECPs, but the risk of after treatment with the regimen, leading to the conclu- drowsiness was doubled (to about 30%).Antinausea sion that combined ECPs may act by impairing endome- medicines are not routinely offered in the United States.
trial receptivity to implantation of a fertilized egg.
Many providers recommend instead that women reduce However, other studies have found no such effects on the the risk of nausea by taking ECPs with food, although re- endometrium.Additional possible mechanisms in- search suggests that doing so is ineffective.
clude interference with corpus luteum function, thicken-ing of the cervical mucus resulting in trapping of sperm, alterations in the tubal transport of sperm, egg, or em-bryo, and direct inhibition of fertilization.No clin- Almost all women can safely use combined ECPs. Ac- ical data exist regarding the last 3 of these possibilities.
cording to the WHO, the only absolute contraindication Nevertheless, statistical evidence on the effectiveness of to use of combined ECPs is confirmed pregnancy, sim- combined ECPs suggests that there must be a mechanism ply because ECPs will not work if a woman is preg- of action other than delaying or preventing ovulation.
naTreatment may also not be appropriate for ECPs do not interrupt an established pregnancy, defined those who have an active migraine with marked neuro- by the National Institutes of Health/FDAand the logic symptoms or crescendo migraine.Given the very American College of Obstetricians and Gynecologists short duration of exposure and low total hormone con- tent, however, combined ECP treatment can be consid- an informed choice, women must know that combined ered safe for women who would ordinarily be cautioned ECPsdlike all regular hormonal contraceptives such against use of combined oral contraceptives for ongoing as the birth control pill, the patch Evra, the vaginal ring contraception. Although no changes in clotting factors NuvaRing, the injectable Lunelle, and the injectable De- have been detected after combined ECP treatment, po-Provera (Pharmacia Corporation, Peapack, NJ), progestin-only ECPs or insertion of a copper IUD and even breastfeedingdmay prevent pregnancy by may be preferable to use of combined ECPs for a woman delaying or inhibiting ovulation, inhibiting fertilization, who has a history of stroke or blood clots in the lungs or or inhibiting implantation of a fertilized egg.
legs and wants emergency contraception. All 3 of theseconditions (pregnancy, migraine, or history of throm- boembolism) are identified through medical historyscreening, so women requesting combined ECPs can Progestin-only ECPs contain no estrogen. Only the pro- be evaluated via telephone, without need for an office gestin levonorgestrel has been studied for freestanding visit, pelvic examination, or laboratory tests. Planned use as an emergency contraceptive. The treatment sched- Parenthood Federation of America now allows affiliates ule is one 0.75 mg dose within 72 hours after unpro- tected intercourse, and a second 0.75 mg dose 12 hours after the first dose. The only practical progestin- obstacle to more widespread use of emergency contra- only product available in the United States is Plan-B ception in the United States until the fall of 1998, when (Barr Pharmaceuticals Woodcliff Lake, NJ), approved Preven (Gyne´tics Inc, Somerville, NJ) was approved.
by the FDA as an ECP in July 1999 (). One tablet More recently, a second specially packaged emergency is required for each dose. Aside from Plan-B, the only progestin-only formulation available in the United approved a year later. Although availability of these States is the birth control minipill Ovrette (which con- products has helped, the 2 pharmaceutical companies tains 0.075 mg norgestrel) (Wyeth Pharmaceutical, Col- originally distributing them were very small and were legeville, Pa). Twenty Ovrette tablets are needed for each not able to promote the products on the same scale as dose. The levonorgestrel regimen appears to be as or most contraceptives. For this reason, and because the more effective than the Yuzpe regimen, and definitely dedicated products can cost more, off-label use of regu- has a significantly lower incidence of nausea and vomit- lar ongoing oral contraceptive brands remains popular.
ingaccording to a randomized controlled trial con- Although the FDA has not specifically approved reg- ducted by WHO, progestin-only ECPs reduce the risk ular combined or progestin-only birth control pills or of pregnancy by 88% and are associated with an inci- copper-bearing IUDs for emergency contraception, pro- dence of nausea 50% lower and an incidence of vomit- viding these products for this indication off-label is com- ing 70% lower than that for combined ECPs. Like pletely legal. Once a medication or device has been combined ECPs, progestin-only ECPs are more effective tested and approved for one use, it is a legal and medi- the sooner after unprotected intercourse treatment is ini- cally accepted practice to prescribe it for other appropri- tiated.The most recent trials found that treatment ate For example, many women take birth control is effective when initiated up to 5 days after unprotected pills not to prevent pregnancy, but to regulate their men- intercourseand that a single dose of 1.5 mg is as effec- strual periods, to decrease menstrual cramping, or to tive as two 0.75 mg doses 12 hours apart.Early prevent the recurrence of ovarian cysts, and these uses treatment may inhibit or delay ovulation or interfere are perfectly legal. The FDA’s reproductive health drugs with sperm migration and function at all levels of the advisory committee reviewed research concerning ECP treatment in 1996 and concluded that existing data were sufficient to document the safety and efficacy of this reg-imen, and the agency then took the unusual action of Copper-bearing IUDs can be inserted up to the time of publishing in the Federal Register a notice declaring pregnancy. Thus, if a woman had unprotected inter- ‘‘The Food and Drug Administration (FDA) is an- course 3 days before ovulation occurred in that cycle, nouncing that the Commissioner of Food and Drugs the IUD could prevent pregnancy if inserted up to 10 (the Commissioner) has concluded that certain com- days after intercourse. Because of the difficulty in deter- bined oral contraceptives containing ethinyl estradiol mining the day of ovulation, however, many protocols and norgestrel or levonorgestrel are safe and effective allow insertion up to only 5 days after unprotected inter- for use as postcoital emergency contraception.. The course. Emergency insertion of a copper-bearing IUD is Commissioner bases this conclusion on FDA’s review significantly more effective than use of ECPs, reducing of the published literature concerning this use, FDA’s the risk of pregnancy after unprotected intercourse by knowledge of the safety of combined oral contraceptives more than 99%.Such a degree of effectiveness implies as currently labeled, and on the unanimous conclusion that emergency insertion of a copper-bearing IUD must that these regimens are safe and effective made by the be able to prevent pregnancy after fertilization. A cop- agency’s Advisory Committee for Reproductive Health per-bearing IUD can also be left in place to provide ef- Drugs at its June 18, 1996 meeting.’’ fective ongoing contraception for up to 10 years. But Even though some doctors have been prescribing IUDs are not ideal for all women. Women at risk of sex- emergency contraceptives since the 1970s, no company ually transmitted infections (STIs) may not be good can- already marketing oral contraceptives or IUDs for on- didates for IUDs; insertion of the IUD in these women going contraception has applied to the FDA to market can lead to pelvic infection, which can cause infertility if these products for emergency use. Although consider- untreated. Women not exposed to STIs have little risk of able international research attests to the safety and effi- pelvic infection after IUD insertion.
cacy of emergency contraceptives, manufacturers cannotalso promote these products for postcoital use until they seek and gain formal FDA approval for this specific purpose. Without commercial marketing or advertis-ing, it is not surprising that physicians prescribe emer- The lack of a product specifically packaged, labeled, and gency contraceptives infrequently and rarely provide marketed as an emergency contraceptive was a major information about emergency contraception to women during routine visits. As a consequence, very few women completely confidential, available 24 hours a day in En- know that emergency contraception is available, effec- glish and Spanish, and offer names and telephone num- tive, and safe.A college campus survey found that bers of providers of emergency contraception located while nearly all students were aware of ECPs and knew near the caller’s area. Public service announcements for they were available at the college health centerdbecause print, radio, television, and outdoor venues advertising of an effective publicity campaigndfew knew that com- the Hotline ran in several cities in 1997 and 1998. These bined ECPs were ordinary oral contraceptives, and were the first advertisements about contraception to be many could not distinguish ECPs from mifepristone, a medication taken to induce abortion after pregnancyhas been con One objection to making ECPs more widely available is the concern that women who know they can use ECPs may become less diligent with their ongoing contracep-tive method. However, if used as an ongoing method, Several service delivery innovations involving emergency ECP therapy would be far less effective than most other contraception would help to reduce the number of unin- contraceptive methods: if the typical woman used com- tended pregnancies. Perhaps the greatest impact would bined ECPs for a year; her risk of pregnancy would ex- result from making ECPs available over-the-counter ceed 35% and if she used progestin-only ECPs, she (OTC) without prescription. There are no medical rea- would still have a 20% chance of pregnancy. Therefore, sons why ECPs should remain prescription-only products continued use would not be a rational choice. Moreover, in the United StateThe ACOG recently recom- 1 in 2 women experiences nausea and 1 in 5 women vom- mended that emergency contraceptive pills be available its after taking combined ECPs. If antinausea medicines OTC in the United States,and the Center for Repro- are used with combined ECPs or if progestin-only ECPs ductive Law and Policy has filed a petition with the FDA are used, the incidence of nausea and vomiting would be signed by more than seventy organizations supporting reduced significantly, but not eliminated.This risk is the method’s OTC availability.ECPs are available likely to dissuade such users from having unprotected OTC in Norway (2000) and Sweden (2001). In December, intercourse often. Reported evidence demonstrates that 2003, an FDA advisory committee voted 23 to 4 to sup- making ECPs more widely available does not increase port a switch for plan B from Rx to OTC.
risk taking but instead reduces the incidence of unin- A second-best alternative is enabling women to ob- tain ECPs directly from a pharmacy without having to diligent about ongoing contraceptive use are those most see a physician, as is possible in Alaska, California, likely to seek emergency treatmentFor example, a re- Hawaii, New Mexico, Washington State,Albania, cent study considering the effect of advance ECP provi- Belgium, Benin, Cameroon, some provinces in Cana- sion on regular methods of birth control, women aged Congo, Denmark, Estonia, Finland, France, 16 to 24 receiving emergency contraception supplies in Gabon, Guinea, Guinea-Bissau, India, Israel, Ivory advance were 3 times as likely to use ECPs when needed Coast, Latvia, Madagascar, Mali, Mauritania, Mauri- but did not report higher frequencies of unprotected tius, Namibia, New Zealand, Nigeria, Portugal, Senegal, sex.Another study demonstrated that educating teens South Africa, Sri Lanka, Switzerland, Tunisia, Uganda, about ECPs does not increase their sexual activity levels or use of emergency contraception but increases their A third-best alternative is screening by telephone knowledge about proper administration of the drugs.
or Web site, after which a prescription is called to the And finally, even if ECP availability did adversely affect woman’s pharmacy of choice; several Planned Parent- regular contraceptive use, women are entitled to know hoods offer this service (see Appendix).
Another important step is changing provider prac- To help educate women and men about emergency tices so that women seen by primary and reproductive contraception, the Association of Reproductive Health health care clinicians would be routinely informed about Professionals in Washington and the Office of Population emergency contraception before the need arises; cur- Research at Princeton University sponsor the toll-free rently only 25% of gynecologists and 14% of general practice physicians routinely counsel women in advance LATE) and the Emergency Contraception Web site about emergency contraception.The recent clinical (http://not-2-late.com). Since it was launched on Febru- practice bulletin issued by the ACOGshould help ary 14, 1996, the Hotline has received more than 450,000 calls. More detailed information is available on include a monograph of legal issues for health care pro- the Emergency Contraception Web site, which has re- viders of ECPs produced by the Center for Reproduc- ceived approximately 2,100,000 hits since it was launched tive Law and Policyand a provider packet developed in October 1994. Both the Hotline and the Web site are by the Program for Appropriate Technology in Health and endorsed by many medical organizations (including more widely available in the United States is 1 of the the American Medical Association, the ACOG, and most important steps that can be taken to reduce the in- Planned Parenthood Federation of America). Infor- cidence of unintended pregnancy and the consequent mation could be provided to women (and men!) in a need for abortion.It was estimated that as many culturally sensitive mannerduring counseling or by as 51,000 abortions were averted by use of ECPs in posters, brochures, audio or videocassettes, or wallet cards. Access would be enhanced if clinicians advertisedemergency contraception services and if ECPs were pre-scribed by telephone without the need for an office visit.
A more proactive step would be to prescribe or dispenseECPs to women in advance so the therapy would be im-mediately accessible if the need arises.
Availability would also be enhanced if one of the large pharmaceutical companies active in marketing - Only 25% routinely discuss emergency contra- other contraceptives to the medical community gained FDA approval for and then actively promoted emer- - 80% prescribed ECPs last year (61% of whom - Only 14% routinely discuss emergency contra- - 36% prescribed ECPs last year (83% of whom Emergency contraception is nearly always cost-effective.
Use of combined or progestin-only ECPs reduces expen- ditures on medical care by preventing unintended preg- nancies, which are very costly. Insertion of a copper-T - 68% know there is something a woman can do in IUD is not cost saving in the United States when used the next few days after unprotected sex to prevent solely as an emergency contraceptive. Unlike the other 2 alternatives, however, insertion of a copper-bearingIUD can provide continuous contraceptive protectionfor up to 10 years thereafter, producing savings if used as an ongoing method of contraception for as little as4 months after emergency insertion.Hormonal emer-  Ensure that all office staff (especially those answer- gency contraceptives are cost-effective regardless of ing the telephone) know that you provide emergency whether they are provided when the emergency arises or provided beforehand as a routine preventive mea-  Routinely discuss emergency contraception with Not only would making emergency contraception  Do not require a pelvic exam before prescribing more widely available save medical care dollars, but also additional social cost savings would result. These in- clude not only the monetary costs of unwanted pregnan-  Provide ECPs in advance to clients or give cies and births but also the considerable psychologic prescriptions in advance that can be filled when costs of unintended pregnancy. Moreover, the average medical care cost of unintended births is likely to be  Discuss antinausea medicines with clients greater than the average cost of all births.
 Extend 72-hour window when prescribing ECPs Join the directory of providers listed on the Emergency Contraception Web site and the Emer-  Advertise the availability of emergency contracep- One of every 2 women aged 15 to 44 in the United States has experienced at least 1 unintended pregnancy.Unin-tended pregnancy is a major public health problem that affects not only the individuals directly involved but alsosociety.Emergency contraception, whether combined  Emergency Contraception Web site: http://not-2- estrogen-progestin, progestin-alone, or copper-bearing IUDs, are effective, safe, simple, and readily feasible in  Emergency Contraception Hotline: 1-888-NOT-2- the United States. Making emergency contraceptives  ARHP EC Train-the-Trainer PowerPoint slide set:  Prescription: 1 promethazine hydrochloride (Phe- nergan) 25-mg tablet or suppository 30 minutes to 1  Emergency Contraceptive Pills: Common Legal hour before each ECP dose; repeat as needed every 8 Questions about Prescribing, Dispensing, Repack- aging, and Advertising. New York: The Center forReproductive Law and Policy; 1999. To order, call  Emergency Contraception: Resources for Providers.
1. Henshaw SK. Unintended pregnancy in the United States. Fam Seattle (WA): Program for Appropriate Technology 2. Trussell J, Stewart F, Guest F, Hatcher RA. Emergency in Health; 1997. To order, call 1-800-669-0156.
contraceptive pills: a simple proposal to reduce unintended  Emergency Contraception: Client Materials for pregnancies. Fam Plann Perspect 1992;24:269-73.
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Appropriate Technology in Health; 1998. To order, Fertility, family planning, and women’s health: new data from the1995 National Survey of Family Growth. Vital Health Stat 23 call 1-206-285-3500 or e-mail info@path.org.
 Emergency Oral Contraception. ACOG Practice 4. Van Look PFA, Stewart F. Emergency contraception. In: Hatcher Bulletin. Number 25. Washington (DC): The Col- RA, Trussell J, Stewart F, Cates W, Stewart GK, Guest F, et al, lege; 2001. To order, call 508-750-8400.
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7. Trussell J, Koenig J, Ellertson C, Stewart F. Preventing unintended Planned Parenthood state hotlines and Web sites pregnancy: the cost-effectiveness of three methods of emergencycontraception. Am J Public Health 1997;87:932-7.
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