[T]he Centers for Disease Control and Prevention reported recently that one in nine sexually active women, or 5.8 million women, has used emergency contraceptive pills, such as Plan B. Emergency contraception is a woman’s back-up method to prevent an unwanted pregnancy, and women report using it when they feel their contraceptive method has failed, such as a broken condom, or they do not use a regular contraceptive like birth control pills.
The latest scientific evidence shows that Plan B works mainly by delaying ovulation — not by affecting a fertilized egg.
Some conservative politicians have been stating publicly that emergency contraceptive pills (ECPs), such as Plan B, cause abortions. They may believe that life begins at conception (fertilization of the egg by the sperm) and argue that ECPs disrupt a fertilized egg’s ability to implant in the uterus, which they consider equivalent to abortion. The American Congress of Obstetricians and Gynecologists and experts from the Food and Drug Administration and the National Institutes of Health consider a pregnancy to be established when a fertilized egg settles itself on the wall of the uterus — implantation. A woman is most likely to become pregnant when she ovulates, which is usually about two weeks before her next period. Sperm can live for up to three days. So, if an egg is fertilized, there are still possibly six to 12 days before the implantation may take place.
When ECPs were first developed and information about them was submitted to the FDA for market approval, the drug manufacturers included mention of every possible mechanism on how the pill might work to prevent pregnancy. This included wording about preventing or delaying ovulation, making the sperm or egg less able to meet, and possibly preventing implantation. However, the latest scientific evidence has shown that ECPs such as Plan B mainly work by delaying ovulation — Plan B does not affect implantation and has no effect on existing pregnancies. Several prominent researchers have stated that if in fact Plan B disrupted implantation, it would be 100 percent effective at preventing a pregnancy, and that is not the case.
The most important factor in the ability of Plan B to prevent pregnancy is if it is taken before ovulation, leading researchers to believe that preventing ovulation is its primary mechanism of action. If a woman is already pregnant when she takes Plan B, it will not stop the pregnancy or affect the developing embryo, which implies Plan B does not actually affect implantation. Teva, the manufacturer of Plan B, states in its drug information material that it is “not effective once the process of implantation has begun.”
Even though research is continuing and is showing more and more that Plan B mainly works by inhibiting ovulation, we may never know the exact mechanism of action of ECPs — or, for that matter, many drugs. The action of drugs in a human body is extremely complex and interconnected. But women have the right to know the latest and most accurate information about all medications. And they have the right to make the best decision for themselves related to this information.
The medical data from years of study, and its use as a prescription product, show that Plan B is very safe, even in repeated use. It met all the criteria for safety and efficacy for over-the-counter (OTC) sale and was recommended many times by the FDA Advisory Committee for OTC approval with no age restrictions. The FDA experts’ advice was overridden by Health and Human Services Secretary Kathleen Sebelius, a very unusual process, although she finally allowed its OTC status for those 17 years and older. Age restrictions on emergency contraception have been debated in the courts, and Plan B One-Step is now available to anyone, regardless of age (other brands of emergency contraception are available to anyone 17 years of age or older). The recently lifted restrictions on Plan B One-Step mean that it can be taken with less delay, possibly enhancing its effectiveness as it needs to be taken within 72 hours of unprotected sex for the best results.
It can still be hard for some women to access Plan B in the time frame it needs to be most effective. In Arizona, for example, health care providers do not need to inform a woman, who presents to the emergency department as having been raped, about ECPs and they are not required to have anyone else tell her about ECPs if it is against their personal beliefs. The provider is also not required to refer the woman to someone who will tell her about all her options, including ECPs. Pharmacists also can refuse to dispense Plan B based on their ethical beliefs, seemingly overriding their patients’ beliefs if they are different from their own.
Access to emergency contraception by women is their right and personal choice for a last chance to possibly prevent a pregnancy after unprotected sex. The science shows Plan B to be safe and better than doing nothing. Although Plan B and other ECPs are part of the contraceptive choices women need to have on hand to make their reproductive decisions, they do not replace other more consistent forms of birth control. For more information about Plan B and other ECPs, or to learn about regular contraception methods, contact Planned Parenthood.