Emergency contraception — mechanisms of action

Emergency contraception - A narrative review of literature

BACKGROUND

Emergency contraception includes several methods of contraception that can be used after unprotected sexual intercourse, after failure of any used method of contraception or in case of sexual abuse, to prevent pregnancy.

PURPOSE OF THE STUDY

The aim of the study was to analyze the available methods of emergency contraception, their mechanisms of action, efficacy, forms of administration, clinical applications and possible adverse effects.

MATERIAL AND METHOD

PubMed, Scopus and Cochrane datebases were searched for articles from 2010 to 2024 about emergency contraception.

RESULTS

The analyzed types of emergency contraception included single oral dose of ulipristal acetate, single oral dose of levonorgestrel and intrauterine system releasing levonorgestrel or copper intrauterine device. Taking emergency contraception in the optimum time according to the drug characteristics allows for avoiding pregnancy in more than 90% of cases (depending on the type of emergency contraception and time from unprotected intercourse). The analyzed literature shows that intrauterine copper intrauterine device is the most effective method of emergency contraception, also together with intrauterine system releasing levonorgestrel leading to the lowest rate of adverse effects.

CONCLUSIONS

Taking emergency contraception can result in various adverse effects, therefore it should be introduced after thorough analysis of woman's medical history, including gynecological and obstetric history and potential contraindications. Additionally, the patient should receive detailed information about the drug mechanism of efficacy and potential adverse effects.

The Levonorgestrel-Releasing Intrauterine Device as Emergency Contraception: Re-examining the Data

Emergency contraception methods that also deliver ongoing contraception provide the most effective options for individuals hoping to prevent pregnancy after unprotected intercourse. Although the copper intrauterine device (IUD) provides the most effective option for emergency contraception because the device prevents pregnancy when placed before implantation and offers long-acting contraception, uptake by patients has been limited. Recently, the Society of Family Planning issued new guidance recommending the levonorgestrel IUD (LNG-IUD) as an emergency contraception option along with the copper IUD. Here, we review evidence related to this recommendation and conclude that the available data do not support use of the LNG-IUD for emergency contraception. We discuss the mechanisms of action of emergency contraception methods and how these concepts interface with the current political and social landscape of contraception and abortion care. We describe limitations of the existing evidence supporting use of the LNG-IUD as emergency contraception and highlight the critical research needed to establish the device as a highly effective method of emergency contraception.

Emergency contraception - A review

Emergency contraception (EC), or postcoital contraception, is a therapy aimed at preventing unintended pregnancy after an act of unprotected or under-protected sexual intercourse. Options include both emergency contraceptive pills (most commonly containing levonorgestrel or ulipristal acetate) and insertion of an intrauterine device. The aim of this paper is to summarize current evidence surrounding the use of emergency contraceptives and to present an evidence-based approach to EC provision. Emergency contraception is a safe and effective option in preventing unwanted pregnancy, irrespective of age, weight, or breastfeeding status. Efforts should be made to increase their availability, as well as knowledge of these methods, both among patients and healthcare providers.

Forensic Nurses' Understanding of Emergency Contraception Mechanisms: Implications for Access to Emergency Contraception

BACKGROUND

An estimated 25,000 pregnancies result from sexual assault in the United States annually. Numerous professional healthcare organizations endorse offering emergency contraception (EC) as an integrated aspect of post-sexual-assault care. Lack of knowledge surrounding EC's mechanism of action, including misinterpreting ECs as abortifacients, might restrict patient access to this important healthcare option.

PURPOSE

We evaluated sexual assault nurse examiners' understanding of the mechanism of action of oral ECs levonorgestrel (LNG) and ulipristal acetate (UPA).

METHODS

A cross-sectional survey of practicing sexual assault nurse examiners was conducted through the International Association of Forensic Nurses.

RESULTS

Among 173 respondents, 96.53% reported they prescribed/dispensed EC at the time of medical forensic examinations. LNG was prescribed more frequently than UPA (57.80% vs. 38.2%, respectively). When asked if they agreed or disagreed if LNG and UPA can disrupt an established pregnancy, 83.2% selected disagree/strongly disagree for LNG versus 78.6% for UPA, which were not significantly different. When asked whether the Supreme Court ruling overturning Roe v. Wade would change their EC prescribing, 79.77% reported it will have no change, 6.94% said it would increase, and 12.72% reported they were unsure. Several commented they were concerned whether state laws would prohibit EC and at least one program stopped prescribing EC because of their state laws.

IMPLICATIONS

Addressing misinformation regarding EC's mechanism of action and increasing access to oral EC options after sexual assault have the potential to reduce the incidence of rape-related pregnancy.

Society of Family Planning Clinical Recommendation: Emergency contraception

Emergency contraception (EC) refers to several contraceptive options that can be used within a few days after unprotected or under protected intercourse or sexual assault to reduce the risk of pregnancy. Current EC options available in the United States include the copper intrauterine device (IUD), levonorgestrel (LNG) 52 mg IUD, oral LNG (such as Plan B One-Step, My Way, Take Action), and oral ulipristal acetate (UPA) (ella). These clinical recommendations review the indications, effectiveness, safety, and side effects of emergency contraceptive methods; considerations for the use of EC by specific patient populations and in specific clinical circumstances and current barriers to emergency contraceptive access. Further research is needed to evaluate the effectiveness of LNG IUDs for emergency contraceptive use; address the effects of repeated use of UPA at different times in the same menstrual cycle; assess the impact on ovulation of initiating or reinitiating different regimens of regular hormonal contraception following UPA use; and elucidate effective emergency contraceptive pill options by body mass indices or weight.

Clinical Update on Uses for Mifepristone in Obstetrics and Gynecology

IMPORTANCE

Mifepristone (RU-486) is a selective progesterone receptor modulator that has antagonist properties on the uterus and cervix. Mifepristone is an effective abortifacient, prompting limitations on its use in many countries. Mifepristone has many uses outside of induced abortion, but these are less well known and underutilized by clinicians because of challenges in accessing and prescribing this medication.

OBJECTIVES

To provide clinicians with a history of the development of mifepristone and mechanism of action and safety profile, as well as detail current research on uses of mifepristone in both obstetrics and gynecology.

EVIDENCE ACQUISITION

A PubMed search of mifepristone and gynecologic and obstetric conditions was conducted between January 2018 and December 2021. Other resources were also searched, including guidelines from the American College of Obstetricians and Gynecologists and the Society of Family Planning.

RESULTS

Mifepristone is approved by the Food and Drug Administration for first-trimester medication abortion but has other off-label uses in both obstetrics and gynecology. Obstetric uses that have been investigated include management of early pregnancy loss, intrauterine fetal demise, treatment of ectopic pregnancy, and labor induction. Gynecologic uses that have been investigated include contraception, treatment of abnormal uterine bleeding, and as an adjunct in treatment of gynecologic cancers.

CONCLUSIONS AND RELEVANCE

Mifepristone is a safe and effective medication both for its approved use in first-trimester medication abortion and other off-label uses. Because of its primary use as an abortifacient, mifepristone is underutilized by clinicians. Providers should consider mifepristone for other indications as clinically appropriate.

Emergency Contraception: Access and Challenges at Times of Uncertainty

BACKGROUND

The UN Commission on Life-Saving Commodities for Women's and Children's Health identified emergency contraceptive pills as 1 of the 13 essential underused, low-cost, and high-impact commodities that could save the lives of millions of women and children worldwide. In the US, 2 emergency contraceptive regimens are currently approved, and their most plausible mechanism of action involves delaying and/or inhibiting ovulation.

AREAS OF UNCERTAINTY

Abortion and contraception are recognized as essential components of reproductive health care. In the US, in the wake of the Dobbs v. Jackson Women's Health Organization Supreme Court decision on June 24, 2022, 26 states began to or are expected to severely restrict abortion. It is anticipated that these restrictions will increase the demand for emergency contraception (EC). Several obstacles to EC access have been described, and these include cost, hurdles to over-the-counter purchase, low awareness, myths about their mechanisms of action, widespread misinformation, and barriers that special populations face in accessing them. The politicization of EC is a major factor limiting access. Improving sex education and health literacy, along with eHealth literacy, are important initiatives to improve EC uptake and access.

DATA SOURCES

PubMed, The Guttmacher Institute, Society of Family Planning, American College of Obstetrician and Gynecologists, the World Health Organization, The United Nations.

THERAPEUTIC ADVANCES

A randomized noninferiority trial showed that the 52 mg levonorgestrel intrauterine device was noninferior to the copper intrauterine device when used as an EC method in the first 5 days after unprotected intercourse. This is a promising and highly effective emergency contraceptive option, particularly for overweight and obese patients, and a contraceptive option with a different bleeding profile than the copper intrauterine device.

CONCLUSIONS

EC represents an important facet of medicine and public health. The 2 medical regimens currently approved in the US are very effective, have virtually no medical contraindications, and novel formulations are actively being investigated to make them more convenient and effective for all patient populations. Barriers to accessing EC, including the widespread presence of contraception deserts, threaten to broaden and accentuate the already existing inequities and disparities in society, at a time when they have reached the dimensions of a public health crisis.

Now Is the Time to Safeguard Access to Emergency Contraception Before Abortion Restrictions Sweep the United States

Abortion and contraception are essential components of reproductive healthcare. As 26 states are likely to severely restrict access to abortion following the Supreme Court decision in Dobbs v. Jackson Women's Health Organization, access to emergency contraception will be more important than ever. Existing barriers to emergency contraception - including cost, obstacles to over-the-counter purchase, low awareness and availability of the most effective options, myths about safety and mechanism of action - already substantially limit access. Proactive solutions include public information campaigns; healthcare provider education about all emergency contraceptive options, including IUDs and advance provision of emergency contraceptive pills; innovative service delivery options such as vending machines and community distribution programs; and policy initiatives to ensure insurance coverage, eliminate pharmacy refusals, and support all service delivery options. In addition, we urge the U.S. Food and Drug Administration to approve updated labeling to align with the best available evidence that oral contraceptive pills work before ovulation and do not prevent implantation of a fertilized egg, as this language contributes to public confusion and access barriers. In the face of extreme limits on reproductive healthcare, now is the time to expand and protect access to emergency contraception so that everyone has the possibility of preventing pregnancy after unprotected sex or sexual assault.

Emergency Contraception Access and Counseling in Metropolitan and Nonmetropolitan Pharmacies in Georgia

Background: Emergency contraception (EC) efficacy is dependent on timing of administration. Adequate pharmacy stock information and accurate patient counseling are important to ensure timely access. Objective: This study evaluates pharmacist reported availability and counseling for levonorgestrel (LNG) and ulipristal acetate (UPA), and identifies differences between caller type and pharmacies in metropolitan vs nonmetropolitan areas of Georgia. Methods: This prospective, randomized, telephone-based study included 25% of Georgia community pharmacies, stratified by geographic location. Calls were made by investigators, first posing as a mystery shopper inquiring about EC stock and efficacy, then 3-6 weeks later as a researcher inquiring about EC stock. Analysis utilized descriptive statistics, chi Square, and logistic regression. Results: Of 600 pharmacies, the mystery shopper caller reached 86%: 74% of pharmacists initially discussed LNG, 57.1% had it stocked, more often in metropolitan areas (OR 1.7, 95% CI 1.08-2.6). Ulipristal acetate was discussed by 1.9% and reported in-stock < 1%. Of those who discussed window of efficacy, 79% indicated LNG would either not work 4 days after intercourse or they were unsure. The research caller successfully completed a second call for 64% of pharmacies: 57% stocked LNG, 3% stocked UPA, and UPA was more likely to be stocked in metropolitan pharmacies. Conclusion: In Georgia, UPA availability is poor, and nonmetropolitan pharmacies were less likely to stock LNG and UPA. A minority of pharmacists correctly indicated that LNG may work up to 120 hours after intercourse. Strategies are needed to overcome barriers to EC availability in community pharmacies and support pharmacists' EC counseling.

The FDA ought to change Plan B's label

This commentary defends 3 arguments for changing the label of levonorgestrel-based emergency contraception (LNG EC) so that it no longer supports the possibility of a mechanism of action after fertilization. First, there is no direct scientific evidence confirming any postfertilization mechanisms. Second, despite the weight of evidence, there is still widespread public misunderstanding over the mechanism of LNG EC. Third, this FDA label is not a value-free claim, but instead it has functioned like a political tool for reducing contraceptive access. The label is laden with antiabortion values (even though EC is contraception, not abortion), and it imposes these values on potential users, resulting in barriers to access such as with Burwell v. Hobby Lobby. These 3 arguments together provide scientific, social, and ethical grounds for the FDA to take the initiate in changing Plan B's drug label.

Differential Effects of the Hormonal and Copper Intrauterine Device on the Endometrial Transcriptome

The contraceptive effectiveness of intrauterine devices (IUDs) has been attributed in part to a foreign body reaction in the endometrium. We performed this study to better understand mechanisms of action of contraceptives of by studying their effects on endometrial and cervical transcriptomes. We collected endometrial and cervical biopsies from women using the levonorgestrel-releasing intrauterine system (LNG-IUS, n = 11), copper intrauterine device (cu-IUD, n = 13) or levonorgestrel-containing combined oral contraceptives (COC, n = 12), and from women not using contraceptives (control group, n = 11). Transcriptional profiling was performed with Affymetrix arrays, Principal Component Analysis and the bioconductor package limma. In endometrial samples from cu-IUD users, there were no genes with statistically significant differential expression compared to controls. In LNG-IUS users, 2509 genes were differentially expressed and mapped predominantly onto immune and inflammatory pathways. The cervical samples showed no statistically significant differential gene expression compared to controls. Hormonal and copper IUDs have significantly different effects on the endometrial transcriptome, with the LNG-IUS transcriptome showing pronounced inflammation and immune activation compared to controls whereas the cu-IUD transcriptome was indistinguishable from luteal phase endometrium. These findings argue against a foreign body reaction as a common mechanism of action of IUDs.

Overview of modern contraception

The large-scale initiatives to address the global unmet needs for family planning (FP) have gathered and compelled scientists, providers, program managers, and other stakeholders (including users) to re-examine the various methods of modern contraception, focusing on those that are proven to be more effective (long-acting reversible contraceptives and permanent methods), historically more widely used (oral contraceptives, condoms), and in development (male hormonal contraception). Implementing FP programs requires an understanding of the human rights principles underpinning the delivery of contraceptive services, the various indicators related to demand, need, and use (demand satisfied, unmet need, and contraceptive prevalence), and its effectiveness (perfect or correct use and typical use), which will be presented in this article. Tools and guidance documents developed using the best available evidence have also been listed in this review article. This issue will also look at new initiatives about providing care (self-care), and key population groups (post-pregnancy and adolescence). The clinical use of the methods should go hand in hand with the programmatic initiatives to ensure that women, men, or couple take up the appropriate method of choice and continue using these based on their reproductive health goals.

"My BMI is too high for Plan B." A changing population of women seeking ulipristal acetate emergency contraception online

Emergency contraceptive (EC) pills may be less effective for women with higher body mass index (BMI), but little is known about public response to the fact that EC may lose efficacy as weight increases. In November 2013, European authorities changed the label for a levonorgestrel EC product to warn of a reduction in effectiveness for women with higher BMI, garnering significant media coverage in the United States. Ulipristal acetate (UPA) EC may be more effective than levonorgestrel for women with BMI levels designated as obese. Among 8,019 women who received UPA from the online pharmacy KwikMed from 2011 to 2015 and self-reported their height, weight and reasons for seeking UPA online, we analyzed changes in the proportion of women in different BMI categories before and after the label change. For the 25 month-period after the label change, the proportion of women in the obese category rose by 26.7 percentage points relative to the 35 months before (B = 0.2665, p < .01). Mean BMI (25.5 versus 29.4, p < .001) and average weight (148.6 pounds versus 175.5 pounds, p < .001) of users were higher after the label change. Some women appear to have acted on the information that EC efficacy may be associated with body weight.

Exploring young women's reasons for adopting intrauterine or oral emergency contraception in the United States: a qualitative study

BACKGROUND

The recent focus on increasing access to long-acting reversible contraceptive methods has often overlooked the diverse reasons why women may choose less effective methods even when significant access barriers have been removed. While the copper intrauterine device (IUD) is considered an acceptable alternative to emergency contraception pills (ECPs), it is unclear to what extent low rates of provision and use are due to patient preferences versus structural access barriers. This study explores factors that influence patients' choice between ECPs and the copper IUD as EC, including prior experiences with contraception and attitudes toward EC methods, in settings where both options are available at no cost.

METHODS

We telephone-interviewed 17 patients seeking EC from three San Francisco Bay Area youth-serving clinics that offered the IUD as EC and ECPs as standard practice, regarding their experiences choosing an EC method. We thematically coded all interview transcripts, then summarized the themes related to reasons for choosing ECPs or the IUD as EC.

RESULTS

Ten participants left their EC visit with ECPs and seven with the IUD as EC option. Women chose ECPs because they were familiar and easily accessible. Reasons for not adopting the copper IUD included having had prior negative experiences with the IUD, concerns about its side effects and the placement procedure, and lack of awareness about the copper IUD. Women who chose the IUD as EC did so primarily because of its long-term efficacy, invisibility, lack of hormones, longer window of post-coital utility, and a desire to not rely on ECPs. Women who chose the IUD as EC had not had prior negative experiences with the IUD, had already been interested in the IUD, and were ready and able to have it placed that day.

CONCLUSIONS

This study highlights that women have varied and well-considered reasons for choosing each EC method. Both ECPs and the copper IUD are important and acceptable EC options, each with their own features offering benefits to patients. Efforts to destigmatize repeated use of ECPs and validate women's choice of either EC method are needed to support women in their EC method decision-making.

Levonorgestrel IUD: is there a long-lasting effect on return to fertility?

Intrauterine devices (IUDs) are effective and safe long-acting reversible contraceptive methods for preventing unplanned pregnancies. While extensive studies were conducted to evaluate return to fertility after removal of IUDs, majority of them were focused on multiparous women using copper IUDs. Current trends indicate increased use of levonorgestrel (LNG) IUDs in nulliparous women for very long periods of time, with both nulliparity and long duration of LNG-IUD use being potentially associated with trends towards longer time to conception post removal. Understanding the effects that LNG-IUDs may have on endometrial morphology and gene expression has important implications to further understanding their mechanism of action. Studies examining endometrial gene expression show persistent changes in receptivity markers up to 1 year after removal of an inert IUD, and no similar studies have been performed after removal of LNG-IUDs. Given the current gap in the literature and trends in LNG-IUD use in nulliparous young women, studies are needed that specifically look at the interaction of nulliparity, long-term use of LNG-IUD, and return to normal fertility. Herein, we review the available literature on the mechanism of action of IUDs with a specific focus on the effect on endometrial gene expression profile changes associated with IUDs.

Long-acting reversible contraception: A route to reproductive justice or injustice

This article presents information on unintended pregnancies and the ongoing efforts of policy makers to promote long-acting reversible contraception (LARC) to reduce the numbers of such pregnancies. Also discussed is the tension between the encouragement of LARC to promote the public's interests in achieving that goal versus the need to assure that all women can decide about their bodies and reproductive needs. Our discussion includes information, primarily from the United States, on (a) risks associated with unintended pregnancies, (b) LARC devices approved in the United States (copper intrauterine devices (IUDs), hormone IUDs, and implants), (c) public and social benefits of increasing the use of LARC, (d) disadvantages and barriers to using LARC, (e) dangers of promoting LARC in unjust ways, and (f) the meaning of reproductive justice and its connection to social justice. By sharing the information with the audience of this journal, we hope that it will be integrated into clinical work and research on mental health and development. We also hope that experts in those fields will become discussants in the conversation regarding women's reproductive health and social justice that is taking place in the United States and elsewhere.

Ulipristal acetate compared to levonorgestrel emergency contraception among current oral contraceptive users: a cost-effectiveness analysis

OBJECTIVE

To estimate the cost-effectiveness of ulipristal acetate (UPA) and levonorgestrel (LNG) emergency contraception (EC) on pregnancy prevention among combined oral contraceptive (COC) pill users with an extended pill-free interval. We accounted for the potential interaction of COCs and obesity on EC efficacy.

METHODS

We built a decision-analytic model using TreeAge software to evaluate the optimal oral EC strategy in a hypothetical cohort of 100,000 twenty-five-year-old women midcycle with a prolonged "missed" pill episode (8-14 days). We used a 5-year time horizon and 3% discount rate. From a healthcare perspective, we obtained probabilities, utilities and costs inflated to 2018 dollars from the literature. We set the threshold for cost-effectiveness at a standard $100,000 per quality-adjusted life-year. We included the following clinical outcomes: number of protected cycles, unintended pregnancies, abortions, deliveries and costs.

RESULTS

We found that UPA was the optimal method of oral EC, as it resulted in 720 fewer unintended pregnancies, 736 fewer abortions and 80 fewer deliveries at a total cost savings of $50,323 and 79 additional adjusted life-years. UPA continued to be the optimal strategy even in the case of obesity or COCs impacting UPA efficacy, in which a COC interaction would have to change efficacy of UPA by 160% before LNG was the dominant strategy.

CONCLUSION

Our models found that UPA was the dominant choice of oral EC among COC users with a prolonged "missed" pill episode, regardless of body mass index or an adverse interaction of COCs on UPA.

IMPLICATIONS

Ulipristal acetate is the dominant choice of oral emergency contraception among combined oral contraceptive users.

Ovulation: Parallels With Inflammatory Processes

The midcycle surge of LH sets in motion interconnected networks of signaling cascades to bring about rupture of the follicle and release of the oocyte during ovulation. Many mediators of these LH-induced signaling cascades are associated with inflammation, leading to the postulate that ovulation is similar to an inflammatory response. First responders to the LH surge are granulosa and theca cells, which produce steroids, prostaglandins, chemokines, and cytokines, which are also mediators of inflammatory processes. These mediators, in turn, activate both nonimmune ovarian cells as well as resident immune cells within the ovary; additional immune cells are also attracted to the ovary. Collectively, these cells regulate proteolytic pathways to reorganize the follicular stroma, disrupt the granulosa cell basal lamina, and facilitate invasion of vascular endothelial cells. LH-induced mediators initiate cumulus expansion and cumulus oocyte complex detachment, whereas the follicular apex undergoes extensive extracellular matrix remodeling and a loss of the surface epithelium. The remainder of the follicle undergoes rapid angiogenesis and functional differentiation of granulosa and theca cells. Ultimately, these functional and structural changes culminate in follicular rupture and oocyte release. Throughout the ovulatory process, the importance of inflammatory responses is highlighted by the commonalities and similarities between many of these events associated with ovulation and inflammation. However, ovulation includes processes that are distinct from inflammation, such as regulation of steroid action, oocyte maturation, and the eventual release of the oocyte. This review focuses on the commonalities between inflammatory responses and the process of ovulation.

Pericoital contraception

PURPOSE OF REVIEW

To evaluate the literature on repeat use of emergency contraception and pericoital approaches to contraception.

RECENT FINDINGS

Women are very interested in an oral, on-demand contraceptive option, were one available. Ulipristal acetate and a combination of levonorgestrel (LNG) and meloxicam (a cyclo-oxygenase-2 inhibitor) both appear to be more effective at disrupting ovulation than LNG alone. Recent advisories from the United Kingdom regarding daily dosing of ulipristal for fibroids emphasize the need for more safety data.

SUMMARY

Repeat pericoital dosing of 1.5-mg LNG is approximately as effective as other on-demand contraceptive methods and is overall very safe. The most common side effect is irregular bleeding. Repeat on-demand ulipristal acetate or meloxicam/other cyclo-oxygenase-2 inhibitors have potential as an on-demand option either alone or in combination but have not been evaluated for contraceptive efficacy in a large-scale study. Given the high unmet need for contraception, even among women with access to available options, there is a distinct need for options that address needs of women who are interested in an on-demand option. On-demand oral contraception has the potential to expand the convenience of contraceptive options and overall contraceptive use.

Muftis in the Matrix

English- and Arabic-language cyberfatwas on emergency contraception (EC) illuminate current debates around sexuality in the global Muslim community. In websites with fatwas about EC, there are significant differences in the way that English- and Arabic-language fatwa websites discuss this reproductive health technology. During the study period of 2016–17, English-language sites were more likely to rule that EC was not religiously acceptable, whereas no Arabic-language online fatwas declared the technology forbidden to Muslims. In contrast, Arabic questions to online fatwa sites were more concerned about whether EC would facilitate illicit sex and the health risks of contraceptives. Only English-language sites discussed the morality of pharmacists providing EC. These websites and fatwas reveal different visions of Muslims’ relationships with technology, science, and scientific experts. They also suggest the influence of non-Islamic religious constituencies on Muslim interpretations of reproductive health technologies.

State of emergency contraception in the U.S., 2018

Emergency contraception is indicated in instances of unprotected sexual intercourse, including reproductive coercion, sexual assault, and contraceptive failure. It plays a role in averting unintended pregnancies due to inconsistent use or non-use of contraception. Options for emergency contraception vary by efficacy as well as accessibility within the U.S. This paper provides an overview of levonorgestrel (Plan B One-Step and generic counterparts), ulipristal acetate (sold as ella), and the copper intrauterine device (IUD, sold as ParaGard), including the mechanisms of action, administration, efficacy, drug interactions, safety, side effects, advantages, and drawbacks. It will also review current misconceptions about emergency contraception and access for subpopulations, including adolescents, immigrants, survivors of sexual assault, rural populations, and military/veteran women. This paper will address barriers such as gaps in knowledge, and financial, health systems, and practice barriers. Continuing areas of research, including the impact of body weight on the efficacy of emergency contraceptive pills and potential interactions between ulipristal acetate and ongoing hormonal contraceptives, are also addressed.

The politics of place: Presidential voting patterns and providers' prescription of emergency contraception

OBJECTIVE

The most effective forms of emergency contraception (EC) require a prescription or a medical procedure; therefore, provider willingness to offer EC remains critical to patient access. This study seeks to assess whether political alignment of a provider's county is associated with provider attitudes and behaviors regarding EC.

STUDY DESIGN

We analyzed survey data collected from 1313 healthcare providers from February 2013 to April 2014 at 14 academic medical centers in the United States. Using logistic regression, we estimated associations between the county political alignment of a provider's practice and his or her EC-related beliefs and practices: 1) if the provider is aware of the most effective EC methods; 2) if knowing that a hypothetical EC method prevented implantation would make a provider less likely to prescribe that method because of personal ethical or religious reasons; and 3) if the provider prescribes any form of EC in his or her practice.

RESULTS

In multivariate models, a one percentage-point increase in county Republican vote share was associated with a 2.9% decrease in the odds of a provider prescribing EC, after accounting for provider knowledge and attitudes about EC.

CONCLUSIONS

EC provides a critical last chance to prevent pregnancy after unprotected sex, yet women living in Republican-leaning counties may face difficulty obtaining EC from healthcare providers. Programs seeking to improve access to EC should focus on areas likely to have fewer providers willing to prescribe EC, which may be those that are more Republican-leaning.

IMPLICATIONS

The most effective forms of emergency contraception require a prescription or a medical procedure; therefore, provider willingness to offer EC remains critical to patient access. Women living in Republican-leaning counties may face difficulty obtaining emergency contraception from healthcare providers.

Update on emergency contraception

PURPOSE OF REVIEW

Emergency contraception provides a critical and time-sensitive opportunity for women to prevent undesired pregnancy after intercourse. Both access and available options for emergency contraception have changed over the last several years.

RECENT FINDINGS

Emergency contraceptive pills can be less effective in obese women. The maximum achieved serum concentration of levonorgestrel (LNG) is lower in obese women than women of normal BMI, and doubling the dose of LNG (3 mg) increases its concentration maximum, approximating the level in normal BMI women receiving one dose of LNG. Repeated use of both LNG and ulipristal acetate (UPA) is well tolerated. Hormonal contraception can be immediately started following LNG use, but should be delayed for 5 days after UPA use to avoid dampening the efficacy of UPA. The copper intrauterine device (IUD) is the only IUD approved for emergency contraception (and the most effective method of emergency contraception), but use of LNG IUD as emergency contraception is currently being investigated. Accurate knowledge about emergency contraception remains low both for patients and healthcare providers.

SUMMARY

Emergency contraception is an important yet underutilized tool available to women to prevent pregnancy. Current options including copper IUD and emergency contraceptive pills are safe and well tolerated. Significant gaps in knowledge of emergency contraception on both the provider and user level exist, as do barriers to expedient access of emergency contraception.

A UPLC-MS/MS method for the quantitation of Ulipristal acetate in human serum

The progesterone receptor modulator, Ulipristal acetate (UPA) has proven to be an effective emergency contraceptive. Conflicting data has been reported that suggests different efficacy of the drug in different populations, which may be explained by the systemic exposure to the drug. A UPLC-MS/MS method was developed and validated for the accurate and sensitive measurement of UPA in human serum to address this matter. UPA was extracted from human serum using liquid-liquid extraction with a combination of hexane and dichloromethane. An analytical platform comprising reverse-phase chromatographic separation followed by mass spectrometric detection by positive electrospray ionization in multiple reaction monitoring was used for quantitation of UPA within 7min. The method was linear from 0.1 to 250ng/mL. The matrix effect was minimal and intra- and inter-assay precision and accuracy were all within the acceptable limits. UPA was found to be stable at all processing and storage conditions. The method was used to investigate the pharmacokinetics of UPA in a clinical trial designed to explore the effect of obesity on its bioavailability.

Emergency Contraception Algorithm and Guide for Clinicians

There are currently three forms of emergency contraception: oral levonorgestrel, oral ulipristal acetate, and the copper intrauterine device. The copper intrauterine device is the most effective, followed by ulipristal acetate and levonorgestrel, respectively. Although levonorgestrel is the least effective method, studies show that more prescribers are familiar with it and that is the most frequently used method. Clinicians should consider several factors when helping women make informed medical decisions regarding emergency contraception, including access to the products, a woman's individual preference, timing since unprotected intercourse, body mass index or weight, and initiation or resumption of routine contraception. This article explains and summarizes these considerations and provides an algorithm to guide clinicians.

Quick starting hormonal contraception after using oral emergency contraception: a systematic review

INTRODUCTION

Unprotected intercourse after oral emergency contraception (EC) significantly increases pregnancy risk. This underlies the importance of promptly starting effective, ongoing contraception - known as 'quick starting'. However, theoretical concern exists that quick starting might interact with EC or hormonal contraception (HC) potentially causing adverse side effects.

METHOD

A systematic review was conducted, evaluating quick starting HC after oral EC [levonorgestrel 1.5 mg (LNG) or ulipristal acetate 30 mg (UPA)]. PubMed, EMBASE, The Cochrane Library, ICTRP, ClinicalTrials.gov and relevant reference lists were searched in February 2016. A lack of comparable studies prevented meta-analysis.

RESULTS

Three randomised controlled trials were identified. Two biomedical studies suggested HC action was unaffected by quick starting after UPA; one study examined ovarian quiescence (OR 1.27; 95% CI 0.51-3.18) while taking combined oral contraception (COC). Another assessed cervical mucus impenetrability (OR 0.76; 95% CI 0.27-2.13) while taking progestogen-only pills (POP). Quick starting POP reduced the ability of UPA to delay ovulation (OR 0.04; 95% CI 0.01-0.37). Side effects (OR 1.22; 95% CI 0.48-3.12) and unscheduled bleeding (OR 0.53; 95% CI 0.16-1.81) were unaffected by quick starting COC after UPA. Another study reported higher self-reported contraceptive use at 8 weeks among women quick starting POP after LNG, compared with women given LNG alone (OR 6.73; 95% CI 2.14-21.20).

Pregnancy Outcomes Following Ulipristal Acetate Emergency Contraception Failure: A Report of Five Cases

INTRODUCTION

The emergency contraceptive ulipristal acetate (UPA) 30 mg is increasingly used by women, but there is no published data on UPA exposure in pregnancy.

CASE REPORT

Here we describe five cases of unintended pregnancies following the use of UPA for emergency contraception. Of five pregnant women exposed to UPA, one decided to terminate the pregnancy for personal reasons. Two of them experienced premature rupture of membranes and the babies were born large for gestational age (LGA). The other two women experienced gestational diabetes, and one of them also delivered a LGA baby. The blood glucose levels of the mothers were normal after delivery and at six weeks postpartum. No birth defects and no growth or developmental abnormalities for the infants were reported during 6 months follow-up.

CONCLUSION

Pregnant women inadvertently exposed to UPA should be monitored carefully, unless further data are available.

Optimizing maternal and neonatal outcomes with postpartum contraception: impact on breastfeeding and birth spacing

Postpartum contraception is important to prevent unintended pregnancies. Assisting women in achieving recommended inter-pregnancy intervals is a significant maternal-child health concern. Short inter-pregnancy intervals are associated with negative perinatal, neonatal, infant, and maternal health outcomes. More than 30% of women experience inter-pregnancy intervals of less than 18 months in the United States. Provision of any contraceptive method after giving birth is associated with improved inter-pregnancy intervals. However, concerns about the impact of hormonal contraceptives on breastfeeding and infant health have limited recommendations for such methods and have led to discrepant recommendations by organizations such as the World Health Organization and the U.S. Centers for Disease Control and Prevention. In this review, we discuss current recommendations for the use of hormonal contraception in the postpartum period. We also discuss details of the lactational amenorrhea method and effects of hormonal contraception on breastfeeding. Given the paucity of high quality evidence on the impact on hormonal contraception on breastfeeding outcomes, and the strong evidence for improved health outcomes with achievement of recommended birth spacing intervals, the real risk of unintended pregnancy and its consequences must not be neglected for fear of theoretical neonatal risks. Women should establish desired hormonal contraception before the risk of pregnancy resumes. With optimization of postpartum contraception provision, we will step closer toward a healthcare system with fewer unintended pregnancies and improved birth outcomes.

Access to Emergency Contraception in the Over-the-Counter Era

INTRODUCTION

After years of complex regulatory changes, levonorgestrel (LNG) emergency contraception (EC) is now approved for unrestricted sale in the United States. Timely access to EC pills is critical because they are more likely to work the sooner they are taken. This study assesses whether LNG EC is sold in accordance with current Food and Drug Administration regulations.

METHODS

We distributed an online questionnaire through an EC-focused listserv for reproductive health professionals, asking data collectors to visit local stores and document product names, price, over-the-counter shelf availability, and misinformation about age restrictions. We used χ2 analysis to assess bivariate associations and t tests and Wilcoxon rank-sum tests to determine differences in means.

RESULTS

We collected information about 220 stores. The majority (65%) stocked EC on over-the-counter shelves, although only 22% of these displayed it without a locked security enclosure. Chain pharmacies were more likely to shelf-stock EC than independent pharmacies (77% vs. 5%; p = .000), but variation existed among stores within the same chain. Among stores that were asked, 40% incorrectly reported an age restriction for non-prescription purchase of LNG EC, whereas 95% correctly reported that men can buy LNG EC. The average price of branded and generic LNG EC was $49.64 and $40.05, respectively.

CONCLUSIONS

Changes in the regulatory status of LNG EC have resulted in widespread confusion about how EC can be sold, and its high price contributes to access barriers. Retailers should ensure that consumers can access LNG EC quickly and easily by stocking the product on over-the-counter shelves and educating staff about current regulations.

"I don't know what I would have done." Women's experiences acquiring ulipristal acetate emergency contraception online from 2011 to 2015

OBJECTIVES

This study describes women's reasons for seeking ulipristal acetate (UPA) for emergency contraception (EC) through the only authorized online retailer for UPA EC in the US.

STUDY DESIGN

Women aged 14 to 59 years, living in states that allow prescription medications to be shipped from out-of-state, accessed the KwikMed online pharmacy between January 2011 and December 2015. After completing a medical eligibility screener, women answered optional multiple-choice questions. To obtain UPA through KwikMed, individuals must be female, 50 years of age or younger, not currently pregnant or breastfeeding and not attempting to order UPA more than once within 30 days or more than four times per year.

RESULTS

Over the 5-year period, KwikMed provided 8019 prescriptions for UPA, and the number of women using this service more than tripled over time. Among women who responded to the survey questions (n=7133; response rate = 89%), most sought EC because of a condom failure (45.3%) or because they did not use regular contraception (41.2%). More than half (53.5%) of women reported that they chose UPA because of its effectiveness compared to levonorgestrel EC pills, and 58.9% preferred ordering UPA online because they found it easier than getting it from a doctor, clinic or pharmacy.

CONCLUSIONS

This study documents the importance of providing confidential services for acquiring EC online. Benefits of online access include convenience, less embarrassment, avoiding situations in which a provider might refuse to provide EC because of their own ideological belief and more reliable availability for this time-sensitive contraceptive.

IMPLICATIONS

Though physical, logistical and societal barriers can restrict women's access to EC, this study demonstrates that providing access to UPA online empowers women to obtain EC when they need it.

Effects of low doses of mifepristone on human embryo implantation process in a three-dimensional human endometrial in vitro co-culture system

OBJECTIVES

We wanted to explore the effects of two different low doses (0.5μM and 0.05μM) of mifepristone, exposed during the receptive period, on the human embryo implantation process, using a well-established three-dimensional in vitro cell culture model, specifically developed to study this process.

METHODS

An in vitro three-dimensional cell culture model was constructed using human endometrial cells isolated from the endometrium of proven fertile women, collected on cycle day LH+4. After 5 days of culture, supernumerary human embryos were added and cultured for another 5 days with mifepristone 0.5μM (n=8) or 0.05μM (n=10) or vehicle as control (n=10). The cultures were checked for embryo attachment and terminated. We studied the expression of 16 reported endometrial receptivity markers in the endometrial constructs using real-time polymerase chain reaction.

RESULTS

None of the embryos in 0.5μM of mifepristone attached to the endometrial constructs (p=.004), whereas 4 out of 10 in 0.05μM (p=.3698) and 7 out of 10 embryos in the control group attached to the cultures. We found that most of the studied receptivity markers were significantly altered with mifepristone exposure in a similar direction in both treatment groups. Only IL6 was significantly differentially expressed between the treatment groups (p=.017).

CONCLUSION

We report for the first time that exposure to a low concentration (0.5μM) of mifepristone during the receptive period successfully inhibits human embryo implantation process in vitro. Further, we observed a dose-dependent effect of mifepristone on endometrial receptivity at the functional level.

IMPLICATION

This study contributes new knowledge that low dose of mifepristone during the short period of receptive phase can inhibit endometrial receptivity, which further promotes mifepristone as a contraceptive agent. This could give women a treatment choice to avoid unwanted pregnancy with high efficacy and minimal side effects.

Does levonorgestrel emergency contraceptive have a post-fertilization effect? A review of its mechanism of action

BACKGROUND

Recent studies have identified that levonorgestrel administered orally in emergency contraception (LNG-EC) is only efficacious when taken before ovulation. However, the drug does not consistently prevent follicular rupture or impair sperm function.

OBJECTIVE

The present systematic review is performed to analyze and more precisely define the extent to which pre-fertilization mechanisms of action may explain the drug's efficacy in pregnancy avoidance. We also examine the available evidence to determine if pre-ovulatory drug administration may be associated with post-fertilization effects.

CONCLUSION

The mechanism of action of LNG-EC is reviewed. The drug has no ability to alter sperm function at doses used in vivo and has limited ability to suppress ovulation. Our analysis estimates that the drug's ovulatory inhibition potential could prevent less than 15 percent of potential conceptions, thus making a pre-fertilization mechanism of action significantly less likely than previously thought. Luteal effects (such as decreased progesterone, altered glycodelin levels, and shortened luteal phase) present in the literature may suggest a pre-ovulatory induced post-fertilization drug effect.

LAY SUMMARY

Plan B is the most widely used emergency contraceptive available. It is important for patients and physicians to clearly understand the drug's mechanism of action (MOA). The drug was originally thought to work by preventing fertilization. Recent research has cast doubt on this. Our review of the research suggests that it could act in a pre-fertilization capacity, and we estimate that it could prevent ovulation in only 15 percent or less of cases. The drug has no ability to alter sperm function and limited ability to suppress ovulation. Further, data suggest that when administered pre-ovulation, it may have a post-fertilization MOA.

Mechanism of Action of Ulipristal Acetate for Emergency Contraception: A Systematic Review

Ulipristal acetate (UPA) is now recommended as first choice hormonal emergency contraception (EC), due to its higher efficacy and similar safety compared to Levonorgestrel - EC. Even though all trials demonstrated that the first mechanism of action is inhibition of ovulation, some authors still postulate that a post fertilization effect is also possible, raising the alert on medication and fostering the ethical debate. A Medline database search was performed in order to find recent articles related to UPA's effects on ovulation, on fallopian tube and on endometrium. We also analyzed the effects on sperm function and pregnancy. All studies conclude that UPA is effective in inhibition of ovulation even when administered shortly before LH peak. The effects on fallopian tube are unclear: according to some authors UPA inhibits ciliar beat through an agonistic effect on progesterone receptors, according to others it antagonizes the progesterone-induced ciliar beat decrease. Concerning the action on endometrium and on embryo implantation most of the studies concluded that low dose UPA used for EC has no significant effect on the decrease of endometrial thickness and on embryo's attachment, but these results are still matter of debate. Finally recent evidence suggests that UPA modulates human sperm functions while it has no effect on established pregnancy. To date the majority of the evidence concurs in excluding a post-fertilization effect of UPA, even though more studies are needed to clarify its mechanism of action.