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Article Excerpt
Emergency contraception (EC) is a contraceptive method used to prevent pregnancy. It is recommended for use after intercourse with a known contraceptive failure, such as a broken condom, more than two missed oral contraceptive pills, late administration of depot medroxyprogesterone acetate (DMPA), late application of a new contraceptive patch, and intercourse without a condom or following a sexual assault (Grimes & Raymond, 2002). Women have been using various forms of EC safely and effectively for over 30 years (Ellertson, 1996; Planned Parenthood Federation of America, 2005).
Nurses at all levels are often the first point of contact for a woman who is requesting EC, thus it is particularly important for them to stay abreast of both the facts regarding the use of this product and the current political controversies. It is particularly important for Nurse Practitioners (NPs) working in primary care with adolescents to remain cognizant of the significant barriers that remain for many women of all ages trying to access this important contraceptive tool: (a) inability to obtain a prescription within 72-120 hours, (b) lack of access to health care (including women who are uninsured or those who live in rural areas, far from a health care provider and/or pharmacy), (c) health care providers who do not feel comfortable prescribing EC, and (d) pharmacists who will not fill EC prescriptions.
Types of Emergency Contraception
There are multiple forms of EC available in the United States; the most commonly used is Plan B, which is a progestin-only formulation (Weismiller, 2004). If Plan B is not available, combination estrogen-progestin oral contraceptive pills (OCPs) can be used for the same purpose. The Food and Drug Administration (FDA) has approved 13 OCPs for this purpose. Tables explaining the appropriate use of OCPs as EC are widely available to providers and are publicly available on the Internet (FDA, 1997; Yuzpe, Thurlow, Ramzy, & Leyshon, 1974) (see Table 1, Emergency Contraception Regimens by Brand). Plan B is more desirable than combined estrogen-progestin EC because it is more effective and has a lower side effect profile, but either method has the potential to drastically reduce pregnancy following unprotected sex and should be available to teens. A third method of EC involves the insertion of a copper intrauterine device within 5-7 days of unprotected intercourse, but it is less commonly used--particularly among adolescents--and beyond the scope of this article.
The History of Emergency Contraception
The initial study supporting the use of estrogen and progesterone in combination to prevent pregnancy after an act of unprotected sex was completed at Yale University in 1963 (Croxatto et al., 2001; Morris & van Wagenen, 1966). In 1974, a Canadian researcher named Albert Yuzpe published a paper on the use of existing oral contraceptive pills as a post-coital contraceptive method (Yuzpe et al., 1974). Referred to as the Yuzpe regimen, this regimen of combining specific doses of oral contraceptive pills has been used safely for the last 30 years, mostly by health care providers in their offices or in emergency rooms for women presenting after a sexual assault. For the purpose of this paper, the Yuzpe regimen will be referred to as combined estrogen-progestin EC. In 1993, Princeton University established a Web site that listed the contact information of providers who were willing to prescribe OCPs off-label for this purpose (Reproductive Health Technologies Project, 2005). Three years later, on Valentine's Day of 1996, Princeton and the Reproductive Health Technologies Project expanded this project and launched an EC hotline and now Web site (1-888-NOT-2-LATE; www.not-2-1ate.com) (Office of Population Research at Princeton, 2005).
Since that time, the U.S. Food and Drug Administration (FDA) has approved multiple dedicated forms of EC. In 1997, six brands of oral contraceptive pills were approved specifically for off-label prescription use as EC (FDA, 1997). One year later, the first dedicated product, Preven, received FDA approval (FDA, 1998). Preven is no longer on the market in the United States because of the superior efficacy and tolerability of Plan B and the ease of using combined estrogen-progestin OCPs as EC when Plan B is not available (Office of Population Research at Princeton, 2005). Plan B, the first progestin-only form of EC, was approved in 1999. Two years after the approval of Plan B, Barr Pharmaceuticals submitted an over-the-counter application to the FDA (FDA, 2004). In 2004, the FDA submitted a non-approval letter to Barr Pharmaceuticals, citing lack of evidence regarding use in women under the age of 16. Barr resubmitted the application with the stipulation that it would remain prescription-only for women under 16 years of age. The decision on that application is still pending and has been delayed multiple times, most recently in November, 2005.
Physiological Mechanism of Action for EC
The start of pregnancy is scientifically defined as implantation of the blastocyst in the endometrium of the uterus, an event that generally takes place 5-7 days after fertilization of the egg (Glaiser, 1997). There are three ways that hormonal EC may function to prevent pregnancy: delaying ovulation, preventing fertilization, or preventing implantation of a fertilized egg; the method of action depends on the part of the menstrual cycle the woman is in at the time of unprotected intercourse (Croxatto et al., 2001).
EC is not an abortifacient, and will not harm or cause teratogenic effects to an existing pregnancy (Glaiser, 1997; Croxatto et al., 2001). EC does not function in the same way as Mifepristone (also known...
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