How does Plan B One-Step work as emergency contraception. What is the effectiveness of this over-the-counter medication. Is Plan B One-Step safe for use without a prescription. When should emergency contraception be taken for optimal results.

Understanding Plan B One-Step: A Comprehensive Overview

Plan B One-Step is a widely recognized emergency contraceptive that has revolutionized reproductive healthcare. This single-dose medication contains 1.5 mg of levonorgestrel, a synthetic hormone that has been used in birth control pills for over three decades. As an over-the-counter (OTC) drug, Plan B One-Step offers accessibility to those seeking a backup method of birth control after unprotected intercourse or contraceptive failure.

The Evolution of Plan B One-Step

The journey of Plan B One-Step to become an OTC medication spans several years:

• July 28, 1999: FDA approves the original Plan B for prescription use
• August 24, 2006: Nonprescription availability granted for women 18 and older
• July 10, 2009: Plan B One-Step introduced, available without prescription for women 17 and older
• June 20, 2013: FDA approves Plan B One-Step for nonprescription use without age restrictions

This progression demonstrates the ongoing efforts to improve access to emergency contraception, reflecting a growing understanding of its importance in reproductive health.

The Science Behind Plan B One-Step’s Mechanism of Action

How does Plan B One-Step prevent pregnancy? The primary mechanism of action is by affecting ovulation. The medication works to stop or delay the release of an egg from the ovary, thereby preventing fertilization. This action is similar to that of regular birth control pills but at a higher dose.

Dispelling Misconceptions

Is Plan B One-Step an abortifacient? No, it is not. The medication does not affect an existing pregnancy and will not work if a person is already pregnant. It acts before implantation occurs and does not interfere with a fertilized egg that has already implanted in the uterus.

Effectiveness and Optimal Usage of Plan B One-Step

The efficacy of Plan B One-Step is largely dependent on how quickly it is taken after unprotected intercourse or contraceptive failure. For maximum effectiveness, it should be taken as soon as possible within 72 hours of the event.

Factors Influencing Effectiveness

• Timing of administration
• Body weight
• Other medications being taken
• Individual metabolism

Can Plan B One-Step be less effective for individuals with a higher body mass index (BMI)? Some studies suggest that emergency contraceptives containing levonorgestrel may be less effective in individuals with a BMI over 25. However, it’s important to note that Plan B One-Step is still recommended as a safe option for these individuals, as the benefits outweigh the potential reduced efficacy.

Safety Profile and Side Effects of Plan B One-Step

Plan B One-Step is generally considered safe for use without a prescription. However, like all medications, it may cause some side effects.

Common Side Effects

• Nausea
• Abdominal pain
• Fatigue
• Headache
• Menstrual changes

Are there any long-term risks associated with using Plan B One-Step? Research has not shown any significant long-term risks associated with the use of levonorgestrel emergency contraceptives. However, it’s important to note that Plan B One-Step is not intended for regular use as a primary form of birth control.

Accessibility and Legal Considerations

The availability of Plan B One-Step as an OTC medication has significantly improved access to emergency contraception. However, it’s crucial to understand the legal landscape surrounding its purchase and use.

Age Restrictions and Identification Requirements

As of 2013, there are no age restrictions for purchasing Plan B One-Step in the United States. This means that individuals of any age can buy it without a prescription or identification. However, policies may vary by country and even by individual pharmacies.

Do pharmacists have the right to refuse to sell Plan B One-Step? In some jurisdictions, pharmacists may have “conscience clauses” that allow them to refuse to sell emergency contraception based on personal beliefs. However, many states require pharmacies to ensure that patients can access these medications, even if an individual pharmacist objects.

Plan B One-Step in the Context of Reproductive Health

While Plan B One-Step is an important tool in preventing unintended pregnancies, it’s essential to view it as part of a broader reproductive health strategy.

Emergency Contraception vs. Regular Birth Control

Plan B One-Step is not intended to replace regular contraceptive methods. It’s designed as a backup option for emergencies, such as contraceptive failure or unprotected intercourse. Regular birth control methods, such as hormonal contraceptives, intrauterine devices (IUDs), or barrier methods, are more effective for ongoing pregnancy prevention.

How does the effectiveness of Plan B One-Step compare to regular birth control methods? While Plan B One-Step can be highly effective when used correctly, its efficacy rate (around 75-89%) is lower than that of consistent use of regular birth control methods like the pill (91-99% effective with perfect use) or IUDs (over 99% effective).

Educational Initiatives and Public Awareness

Increasing public awareness about emergency contraception is crucial for ensuring its effective use and dispelling myths and misconceptions.

The Role of Healthcare Providers

Healthcare providers play a vital role in educating patients about emergency contraception. This includes discussing:

• When and how to use Plan B One-Step
• Its effectiveness and limitations
• Potential side effects
• The importance of regular contraception

What strategies can be employed to improve public understanding of emergency contraception? Educational campaigns, school-based sex education programs, and clear, accessible information at pharmacies and healthcare facilities can all contribute to better public awareness and understanding of emergency contraception options like Plan B One-Step.

Future Developments in Emergency Contraception

As research in reproductive health continues, we may see new developments in emergency contraception.

Potential Advancements

• More effective formulations
• Extended window of effectiveness
• Reduced side effects
• Alternative delivery methods

What role might telemedicine play in the future of emergency contraception? The growth of telemedicine could potentially increase access to emergency contraception by allowing individuals to consult with healthcare providers remotely and have medications delivered directly to their homes.

As we look to the future, it’s clear that emergency contraception like Plan B One-Step will continue to play a crucial role in reproductive health. By understanding its mechanism of action, effectiveness, and proper use, individuals can make informed decisions about their reproductive health. As research progresses and public awareness grows, we can expect to see continued improvements in both the accessibility and efficacy of emergency contraception options.

The journey of Plan B One-Step from a prescription-only medication to an over-the-counter option available to all ages represents a significant advancement in reproductive rights and healthcare access. However, it’s important to remember that emergency contraception is just one tool in the broader landscape of reproductive health. Regular contraception, comprehensive sex education, and access to quality healthcare all play crucial roles in preventing unintended pregnancies and promoting overall reproductive well-being.

As we continue to navigate the complex landscape of reproductive health, it’s crucial to stay informed about the latest developments and guidelines. Whether you’re a healthcare provider, educator, or individual seeking information, staying up-to-date on emergency contraception options like Plan B One-Step can help ensure that everyone has the knowledge and resources they need to make informed decisions about their reproductive health.

Remember, while Plan B One-Step is an important option for emergency contraception, it’s not a substitute for regular birth control methods. If you find yourself frequently relying on emergency contraception, it may be worth discussing more reliable long-term contraceptive options with a healthcare provider. By taking a proactive approach to reproductive health, we can work towards a future where every pregnancy is planned and wanted, and where everyone has the tools and knowledge they need to take control of their reproductive futures.

Plan B One-Step (1.5 mg levonorgestrel) Information

Plan B One-Step is an emergency contraceptive, a backup method of birth control. Emergency contraception is used to reduce the chance of pregnancy after unprotected sex (if other birth control failed or was not used). It is not for routine contraceptive use. Plan B One-Step is available as a nonprescription (over-the-counter or OTC) drug.

A brief history of Plan B and Plan B One-Step is as follows:

• On July 28, 1999, FDA approved a new drug application (NDA) for the original product, Plan B, for prescription use.
• On August 24, 2006, FDA approved a supplemental NDA permitting nonprescription availability of Plan B for women 18 years and older and by prescription for women 17 years and younger.
• On July 10, 2009, FDA approved a supplemental NDA permitting nonprescription availability of Plan B for women 17 years and older and by prescription for women 16 years and younger. Plan B has been discontinued and is no longer being marketed.
• On July 10, 2009, FDA also approved Plan B One-Step (PBOS) (levonorgestrel) tablet, 1.5 mg as a nonprescription product for women ages 17 and older, and as a prescription-only product for women ages 16 and below. Plan B used a two-dose regimen with 0.75 mg of levonorgestrel in each tablet to be taken 12 hours apart, while PBOS is a single dose tablet that contains 1.5 mg of levonorgestrel.
• On June 20, 2013, FDA approved PBOS for nonprescription use without age restrictions.

Q. What is emergency contraception?
A. Emergency contraception is a method of preventing pregnancy to be used after another contraceptive fails or after unprotected sex. It is not for routine contraceptive use. Drugs used for this purpose are called emergency contraceptive pills, post-coital pills, or morning-after pills. Emergency contraceptives contain hormonally active drugs.

Q. What is Plan B One-Step?
A. Plan B One-Step is an emergency contraceptive, a backup method to other birth control. It is in the form of one levonorgestrel pill (1.5 mg) that is taken by mouth after unprotected sex or contraceptive failure. Levonorgestrel is a synthetic hormone used in birth control pills for over 35 years. Plan B One-Step is available as a nonprescription (over-the-counter or OTC) drug.

Q. How does Plan B One-Step work?
A. Plan B One-Step works before release of an egg from the ovary. As a result, Plan B One-Step usually stops or delays the release of an egg from the ovary. It is one tablet that contains a higher dose of levonorgestrel than birth control pills and works in a similar way to prevent pregnancy.

Q. Is Plan B One-Step effective?
A. The most important factor affecting how well emergency contraception works is how quickly it is taken after unprotected sex or contraceptive failure. Therefore, FDA recommends that all people using levonorgestrel emergency contraceptives follow the product directions exactly and take the product as soon as possible within 72 hours after unprotected sex or contraceptive failure.

FDA recommends that consumers talk to their health care provider about emergency contraception in advance of needing it and understand the importance of using these products as intended.

Consumers and health care professionals are encouraged to report adverse reactions from the use of Plan B One-Step to the FDA’s MedWatch Adverse Event Reporting program at www.fda.gov/MedWatch or by calling 1-800-FDA-1088.

Q. Is Plan B One-Step an abortifacient (causing abortion)?
A. No. Plan B One-Step will not work if a person is already pregnant, meaning it will not affect an existing pregnancy. Plan B One-Step prevents pregnancy by acting on ovulation, which occurs well before implantation. Evidence does not support that the drug affects implantation or maintenance of a pregnancy after implantation, therefore it does not terminate a pregnancy.

Q. Why was the mechanism of action modified on the Drug Facts label and Consumer Information Leaflet in 2022?
A. The applicant for Plan B One-Step submitted a supplemental new drug application (labeling supplement), as amended, to FDA requesting approval to modify some the mechanism of action information on the Drug Facts label and in the Consumer Information Leaflet.

Based on careful consideration of the applicant’s labeling supplement, as amended, and additional scientific evidence, FDA determined that the labeling for Plan B One-Step should be updated to have the mechanism of action information be primarily in the Consumer Information Leaflet. The mechanism of action in the Consumer Information Leaflet was updated so it is now consistent with the best available scientific evidence.

Q. Why was the mechanism of action in the Drug Facts label changed to remove wording about fertilization and implantation?
A. In response to the submission of the applicant’s labeling supplement, as amended, FDA reviewed currently available scientific evidence regarding the mechanism of action for Plan B One-Step. FDA determined the current science supports a conclusion that Plan B One-Step works by inhibiting or delaying ovulation and the midcycle hormonal changes. The evidence also supports the conclusion that there is no direct effect on fertilization or implantation. FDA also determined that the most appropriate placement of mechanism of action information was primarily in the Consumer Information Leaflet rather than in the Drug Facts label. Accordingly, FDA removed information directly related to the mechanism of action from the “Other Information” section of the Drug Facts label and updated the mechanism of action information in the Consumer Information Leaflet to be consistent with the best available evidence.

The mechanism of action is rarely included in nonprescription drug labeling (and, more specifically, the Drug Facts label) and is not required under FDA’s regulations for nonprescription labeling, as this information is not needed for the safe and effective use of nonprescription drugs in general. Because consumers may be interested in how Plan B One-Step works, information on the mechanism was kept in the Consumer Information Leaflet and updated to be consistent with the best available evidence. Also, both the Drug Facts label and Consumer Information Leaflet retain statements that are consistent with the mechanism of action—that the product will not work if the woman is already pregnant.

Q. Why was the mechanism of action in the Consumer Information Leaflet changed to modify wording about fertilization and implantation?
A. In response to the submission of the applicant’s labeling supplement, as amended, FDA reviewed currently available scientific evidence regarding the mechanism of action for Plan B One-Step. FDA determined the current science supports a conclusion that Plan B One-Step works by inhibiting or delaying ovulation and the midcycle hormonal changes. The evidence also supports the conclusion that there is no direct effect on postovulatory processes, such as fertilization or implantation. Accordingly, FDA updated the mechanism of action information in the Consumer Information Leaflet, which included removing references to the mechanisms not supported by the best available scientific evidence (that is, effects on fertilization and implantation).

Additional information on FDA’s scientific review is available in the decisional memorandum.

Q. Is there information about the mechanism of action that remains on the Plan B One-Step Drug Facts label and the Consumer Information Leaflet that helps inform consumers?
A. The Consumer Information Leaflet includes updated information on the mechanism of action to explain that Plan B One-Step works before release of an egg from the ovary. As a result, Plan B One-Step usually stops or delays the release of an egg from the ovary.

The Drug Facts label and Consumer Information Leaflet continue to include information that relates to when in the reproductive cycle Plan B One-Step works.

Specifically, the Drug Facts label retains the following statement in the “Warnings” section, under “Do not use”: “Do not use if you are already pregnant (because it will not work). ”

In the Consumer Information Leaflet, the following statements are retained:

• Under the heading “What Plan B One-Step is not,” the following statement will remain: “Plan B One-Step will not work if you are already pregnant and will not affect an existing pregnancy.”
• Under the heading “When not to use Plan B One-Step,” the following statement will remain: “Plan B One-Step should not be used if you are already pregnant, because it will not work.”

These statements are consistent with the mechanism of action described in the Consumer Information Leaflet and remind the consumer that Plan B One-Step does not work when a woman is already pregnant. Therefore, when considering when in the reproductive cycle that Plan B One-Step might work, it will be clear to the consumer that Plan B One-Step works very early in the reproductive cycle (prior to ovulation).

Q. Are there generics of Plan B One-Step and will the labeling for these generics be updated to reflect the same labeling changes for Plan B One-Step?
A. There are multiple (11) generics of Plan B One-Step with an active marketing status. The generics for Plan B One-Step are approved for nonprescription use without age restrictions. A generic drug is required to have the same labeling as the reference listed drug except for certain permissible differences, and generic drug holders are expected to update their labeling after FDA has approved relevant changes to the labeling for the corresponding reference listed drug. Accordingly, the generics for Plan B One-Step are expected to update their labeling to reflect the changes made to the Plan B One-Step labeling by submitting their revised labeling as soon as possible.

Additional Resources

• Plan B One-Step labeling from Drugs@FDA
• Decisional Memorandum
• Supplemental Approval letter

Ectopic Pregnancy Risk in Users of Levonorgestrel-Releasing Intrauterine Systems With 52, 19.

5, and 13.5 mg of Hormone | Pregnancy | JAMA

Ectopic Pregnancy Risk in Users of Levonorgestrel-Releasing Intrauterine Systems With 52, 19.5, and 13.5 mg of Hormone | Pregnancy | JAMA | JAMA Network










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Research Letter

March 21, 2023

Amani Meaidi, MD, PhD¹; Christian Torp-Pedersen, MD, MMSc²; Øjvind Lidegaard, MD, DMSc³; et al
Lina Steinrud Mørch, PhD¹

Author AffiliationsArticle Information

• ¹The Danish Cancer Society Research Center, Cancer Surveillance and Pharmacoepidemiology, Copenhagen, Denmark

• ²Department of Cardiology, North Zealand Hospital, Hilleroed, Denmark

• ³Department of Gynecology, Rigshospitalet, Copenhagen, Denmark

JAMA. 2023;329(11):935-937. doi:10.1001/jama.2023.0380

Full Text

The hormone content in levonorgestrel-releasing intrauterine systems (IUSs) must be high enough to maintain optimal contraceptive effect but sufficiently low to minimize progestin-related adverse events.^1,2

Globally marketed levonorgestrel IUSs contain 52 mg, 19.5 mg, and 13.5 mg of levonorgestrel. All are recommended for contraception, with the highest dose also recommended for treatment of heavy menstrual bleeding. The 2 low-dose levonorgestrel IUSs are smaller than the 52-mg levonorgestrel IUS and recommended interchangeably to nulliparous women for easier insertion.¹

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The female hormone levonorgestrel and its effect on the body

A woman’s ability to conceive and bear a child, the regularity of the cycle is determined by the interaction of two hormones in her body. These are the so-called “female” and “male” hormones estrogen and progesterone. Estrogen ensures the stability and regularity of the cycle, that is, the timely maturation and release of the egg into the uterine cavity, and progesterone prepares the uterus for pregnancy.

At the beginning of the 20th century, doctors noticed the ability of large doses of progesterone to suppress ovulation ^[1] . A little later, it was synthesized artificially, and in the form of many derivatives, called progestins or progestogens. One of them is levonorgestrel, a synthetic hormone, an analogue of progesterone, derived from testosterone.

How levonorgestrel affects a woman’s body

Once in the blood, even in a microdose, this synthetic hormone acts as follows ^[2] :

• thickens cervical mucus, thereby narrowing the cervical canal and preventing spermatozoa from entering the uterine cavity ;
• reduces the patency of the fallopian tubes for spermatozoa;
• reversibly suppresses ovulation – that is, after stopping the intake, the cycle is restored after some time without consequences.

Levonorgestrel as a contraceptive

Due to these properties, levonorgestrel is widely used in the manufacture of various contraceptives, either alone or in combination with synthetic estrogen analogues.

Contraceptive products that contain only levonorgestrel include:

• so-called mini-pills, progestin birth control pills. They contain microdoses of the hormone and are designed to be taken within a month;
• emergency contraception (“morning pills” or “plan B” pills). The dose of the hormone in them is slightly higher than in mini-pills, so they can urgently prevent unwanted conception within a few days after unprotected intimate contact. These remedies are most effective within 72 hours after sexual intercourse. To ensure contraceptive action, only 1-2 tablets are enough, depending on the drug.

In addition, in combination with synthetic analogues of estrogens, levonorgestrel is part of a variety of combined oral contraceptives, vaginal rings, intrauterine devices, implants.

For whom is levonorgestrel-based contraception suitable?

Remember that hormonal contraceptives can only be taken with a doctor’s prescription. In the case of taking combined hormonal preparations or using contraceptives based on them, all precautions prescribed for such medicines must be observed. In particular, they cannot be used during pregnancy and lactation, in the presence of estrogen-dependent diseases and a tendency to thrombosis, and they are also undesirable for women who smoke over the age of 35.

Contraindications to the use of monohormonal drugs, such as mini-pills or pills for emergency contraception, are: hypersensitivity to any component of the drug; age up to 16 years; severe liver failure; pregnancy; rare hereditary diseases such as lactose intolerance, lactase deficiency or glucose-lactose malabsorption. With caution, these drugs should be used in diseases of the liver or biliary tract, jaundice (including history), Crohn’s disease, lactation. Among the side effects of drugs containing levonorgestrel, nausea, dizziness, abdominal pain or headache, and fatigue are rarely noted.

The effectiveness of contraceptives based on levonorgestrel is very high, its indicators depend on the form of the drug, the concentration and type of hormones that are active substances in each case. So, for example, for emergency contraceptive pills, the effectiveness is about 98.2% ^[3] .

^[1] Kahlenborn C, Peck R, Severs WB. Mechanism of action of levonorgestrel emergency contraception. The Linacre Quarterly. 2015;82(1):18-33.

^[2] Cleland K, Raymond EG, Westley E, Trussell J. Emergency contraception review: evidence-based recommendations for clinicians. Clinical obstetrics and gynecology. 2014;57(4):741-750.

^[3] Emergency contraception. WHO Bulletin. July 2017. Available online http://www.who.int/mediacentre/factsheets/fs244/en/.

Oral contraceptives

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Levonorgestrel-releasing intrauterine system for endometrial protection in women with breast cancer taking tamoxifen to prevent recurrence

This translation is out of date. Please click here for the latest English version of this review.

Survey question

The Cochrane authors investigated whether an intrauterine levonorgestrel-releasing hormone-releasing system (LNG-IUD) could reduce the risk of endometrial polyps, abnormal thickening of the uterine lining, and endometrial cancer in women taking tamoxifen for breast cancer. This review also examined the effect of LNG-IUD use on the risk of abnormal vaginal bleeding or spotting, fibroids, breast cancer recurrence, or death in women taking tamoxifen for breast cancer.

Relevance

Tamoxifen is widely used by women to reduce the risk of recurrence of breast cancer. Tamoxifen can also cause abnormal changes in the lining of the uterus (endometrium), including polyps and cancer. The LNG-IUD is an intrauterine device that releases the synthetic hormone levonorgestrel into the endometrium and causes marked suppression of endometrial function. Since levonorgestrel is a progestin and many breast cancers are progesterone sensitive, it is important to study the safety of the LNG-IUD in breast cancer survivors.

Study profile

This review includes 17 randomized controlled trials involving 9030 women. The studies took place in the UK, Turkey, Egypt and Hong Kong, and the primary outcome in all studies was pathological changes in the uterine mucosa. Three studies have identified the occurrence of fibroids. Three studies reported abnormal vaginal bleeding or spotting (spotting). Two studies reported cases of breast cancer recurrence, and three studies reported deaths due to breast cancer. The evidence is current to October 2015.

Main results

This review suggests that the LNG-IUD may reduce the risk of endometrial polyps and endometrial hyperplasia over a long-term follow-up period (24 to 60 months) in women taking tamoxifen for breast cancer. At 12 and 24 months of follow-up, more women in the LNG-IUD group experienced abnormal vaginal bleeding or spotting. However, by 60 months of follow-up, neither abnormal vaginal bleeding nor spotting was reported in either group. There was not enough data to show if there was any effect on the incidence of endometrial cancer (cancer originating from glandular tissue), fibroids, recurrence of breast cancer, or death caused by breast cancer.

Quality of evidence:

The quality of the evidence was rated as moderate due to limited sample sizes and low event rates to compare outcomes. More studies are needed to evaluate the effect of the LNG-IUS on the incidence of endometrial cancer, as well as the effect of the LNG-IUS on the risk of secondary events in breast cancer.

Translation notes:

Translation: Aizara Fanilovna Garayeva. Editing: Ziganshina Lilia Evgenievna. Project coordination for translation into Russian: Cochrane Russia – Cochrane Russia (branch of the Northern Cochrane Center on the basis of Kazan Federal University).