Update on Emergency Contraception – EC Methods

(Published March 2011)

EC Methods

Emergency contraceptives available in the United States include emergency contraception pills (ECPs) and the Copper T intrauterine device.1,2,3

ECPs

Three types of ECPs are available in the United States: combined ECPs containing both estrogen and progestin (Yuzpe method), progestin-only ECPs (Table 1), and an ECP containing ulipristal acetate (UPA).

They’re Really Not “Morning-after” Pills

Confusion persists about emergency contraceptives.

They are often called “morning-after” pills, but this is a misnomer for several reasons:

  • They do not need to be taken the morning after unprotected intercourse.
  • They may be taken up to 120 hours (5 days) after unprotected sex.

Combined ECPs contain the hormones estrogen and progestin. The specific agents that have been studied extensively in clinical trials of ECPs are the estrogen ethinyl estradiol and the progestin levonorgestrel or norgestrel. A specially packaged combined ECP (Preven®) was approved by the Food and Drug Administration (FDA) in 1998 but withdrawn from the market in 2004 based on data showing that progestin-only EC was more effective. Combining estrogen and progestin hormones in this manner is also called the Yuzpe method, after the Canadian physician who first described the regimen.

Progestin-only ECPs have largely replaced the combined ECPs because they are more effective and cause fewer adverse effects. Although ECPs are commonly known as “morning-after pills,” the term is misleading; ECPs may be initiated sooner than the name implies or much later than the morning after. Progestin-only ECPs are most effective when taken immediately after unprotected intercourse. Efficacy declines as time elapses between sex and drug administration. Progestin-only ECPs are approved by FDA for use up to 72 hours after intercourse. They are reasonably effective for up to 120 hours and perhaps longer.4 However, patients should remember that progestin-only ECPs are more effective the sooner they are taken after unprotected sex.5-8 While the effectiveness of progestin-only ECPs declines with delay in treatment, the effectiveness of the UPA ECP does not (up to 120 hours).

The progestin-only products currently approved by FDA for use in the United States contain levonorgestrel. Two progestin-only products are currently available in the United States:

  • Next Choice® (two 0.75-mg tablets), approved by FDA in June 2009, is the branded generic of its two-tablet predecessor, Plan B® (first approved by FDA in July 1999).
  • Plan B One-Step® (single 1.5-mg tablet), approved by FDA in July 2009.

The original treatment schedule was one 0.75-mg dose within 72 hours after unprotected intercourse and a second 0.75-mg dose 12 hours later. The 72-hour marker is listed on the label for both of the currently marketed progestin-only ECPs. However, subsequent studies have shown that a single dose of 1.5 mg is as effective as two 0.75-mg doses 12 hours apart.5,6 A single 1.5-mg dose is now considered the evidence-based standard, and it can be effective up to 120 hours after unprotected intercourse. Also, this dosing regimen is easier for women and enhances adherence.

Recently, a second-generation anti-progestin, UPA, was FDA approved for use as EC in the US:

  • ella® (one 30 mg tablet), approved by FDA August 13, 2010, marketed in Europe as ellaOne since October 2009.

A single 30 mg dose can be effective up to 120 hours after unprotected intercourse.

When ECPs specifically indicated for EC are not available, certain other oral contraceptives can be used in specified combinations for EC. The regimen is one dose followed by a second dose 12 hours later, where each dose consists of up to six tablets depending on the brand. Currently, 19 brands of combined oral contraceptives are approved in the United States for use as EC (Table 1).

Table 1: Oral Contraceptives approved for EC in the United States 9
Branda Manufacturer Pills per Dose Ethinyl Estradiol per Dose (mcg) Levonorgestrel per Dose (mg)b
Dedicated emergency contraception (take one dose)
Plan B One-StepTM Teva 1 white pill 0 1.5
Next Choice® Watson 2 peach pills 0 1.5
ella® Watson 1 white pill 0 0c
Combined progestin and estrogen pills (take two does 12 hours apart) d
AvianeTM Teva 5 orange pills 100 0.50
CryselleTM Teva 4 white pills 120 0.60
EnpresseTM Teva 4 orange pills 120 0.50
JolessaTM Teva 4 pink pills 120 0.60
Lessina® Teva 5 pink pills 100 0.50
LevoraTM Watson 4 white pills 120 0.60
Lo/Ovral® Akrimax 4 white pills 120 0.60
LoSeasonique® Teva 5 orange pills 100 0.50
Low-Ogestrel® Watson 4 white pills 120 0.60
LuteraTM Watson 5 white pills 100 0.50
Lybrel® Wyeth 6 yellow pills 120 0.54
Nordette® Teva 4 light-orange pills 120 0.60
Ogestrel® Watcon 2 white pills 100 0.50
Portia® Teva 4 pink pills 120 0.60
Quasense® Watson 4 white pills 120 0.60
Seasonale® Teva 4 pink pills 120 0.60
Seasonique® Teva 4 light-blue-green pills 120 0.60
SronyxTM Watson 5 white pills 100 0.50
Trivora® Watson 4 pink pills 120 0.50
Notes:

a Plan B One-Step, Next Choice, and ella are the only dedicated products specifically marketed for emergency contraception in the United States. Aviane, Cryselle, Enpresse, Jolessa, Lessina, Levora, Lo/Ovral, LoSeasonique, Low-Ogestrel, Lutera, Lybrel, Nordette, Ogestrel, Portia, Quasense, Seasonale, Seasonique, Sronyx and Trivora have been declared safe and effective for use as ECPs by the United States Food and Drug Administration. Outside the United States, more than 100 emergency contraceptive products are specifically packaged, labeled, and marketed. Levonorgestrel-only ECPs are available either over-the-counter or from a pharmacist without having to see a clinician in 60 countries. Plan B One-Step and Next Choice are available over-the counter to women and men aged 17 and older in the United States. A prescription is required for ella for women of all ages.

b The label for Plan B One-Step indicates to take the pill within 72 hours after unprotected intercourse. Research has shown that that all of the brands listed here are effective when used within 120 hours after unprotected sex. The label for Next Choice says to take one pill within 72 hours after unprotected intercourse and another pill 12 hours later. Research has shown that both pills can be taken at the same time with no decrease in efficacy or increase in side effects and that they are effective when used within 120 hours after unprotected sex.

c 30 mg ulipristal acetate within 120 hours after unprotected sex.

d The progestin in Cryselle, Lo/Ovral, Low-Ogestrel and Ogestrel is norgestrel, which contains two isomers, only one of which (levonorgestrel) is bioactive; the amount of norgestrel in each tablet is twice the amount of levonorgestrel.

Copper T IUD

Copper T IUDs can be inserted up to the time of implantation—six to 12 days after ovulation9—to prevent pregnancy. 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 she is not pregnant.10 A copper IUD can also be left in place to provide effective ongoing contraception for up to 12 years.

 

References:

  1. Stewart F, Trussell J, Van Look PFA. Emergency contraception. In: Hatcher RA, Trussell J, Nelson AL, et al., Eds. Contraceptive technology. 19th revised ed. New York: Ardent Media; 2007:87–116.
  2. Glasier A. Emergency postcoital contraception. N Engl J Med. 1997;337:1058–64.
  3. Hatcher RA, Trussell J, Stewart F, et al. Emergency contraception: the nation’s best kept secret. Decatur, GA: Bridging the Gap Communications; 1995.
  4. Trussell J, Raymond EG. Emergency contraception: a last chance to prevent unintended pregnancy. Accessed at http://ec.princeton.edu/questions/ec-review.pdf, June 24, 2010.
  5. von Hertzen H, Piaggio G, Ding J, et al. Low dose mifepristone and two regimens of levonorgestrel for emergency contraception: a WHO multicentre randomised trial. Lancet. 2002;360:1803–10.
  6. Arowojolu AO, Okewole IA, Adekunle AO. Comparative evaluation of the effectiveness and safety of two regimens of levonorgestrel for emergency contraception in Nigerians. Contraception. 2002;66:269–73.
  7. Task Force on Postovulatory Methods of Fertility Regulation. Randomised controlled trial of levonorgestrel versus the Yuzpe regimen of combined oral contraceptives for emergency contraception. Lancet. 1998;352:428–33.
  8. Piaggio G, von Hertzen H, Grimes DA, et al. Timing of emergency contraception with levonorgestrel or the Yuzpe regimen. Lancet. 1999;353:721.
  9. Creinin MD, Schlaff W, Archer DF, et al. Progesterone receptor modulator for emergency contraception: a randomized controlled trial. Obstet Gynecol. 2006;108:1089-97.
  10. Fine P, Mathé H, Ginde S, et al. Ulipristal acetate taken 48-120 hours after intercourse for emergency contraception. Obstet Gynecol. 2010;115:257-63.