Contraceptive efficacy of emergency contraception with levonorgestrel given before or after ovulation

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.

Maximizing the effectiveness of 1.5 mg levonorgestrel for emergency contraception: The case for precoital use

Objectives

U.S. and World Health Organization Selected Practice Recommendations for Contraceptive Use state people may have an advanced supply of emergency contraception (EC) to minimize treatment delays. We sought to characterize the potential improvement in effectiveness of 1.5 mg levonorgestrel (LNG-EC) if it were taken up to a few hours before unprotected sex.

Study design

We expanded on an existing mathematical model for the maximum attainable effectiveness of LNG-EC, assuming it exclusively works to disrupt ovulation, and compared results with point estimates from nine studies when it was taken up to 72 hours after sex. We then modelled how effectiveness might have improved if subjects had taken LNG-EC up to 3 hours before sex.

Results

Taking LNG-EC immediately after sex could potentially reduce the risk of unintended pregnancy by 91%. However, population-average maximum attainable effectiveness levels ranged from just 49% to 67% when accounting for the distributions of postcoital treatment delays in the example studies. If half the subjects had taken it 3 hours before sex, then maximum effectiveness levels would have ranged from 70% to 81%.

Conclusions

At the individual level, taking LNG-EC a few hours before sex is a logical extension of Selected Practice Recommendations regarding an advanced supply of EC and, based on our modeling, should be advocated for people who can reasonably anticipate an unprotected sex act. In the absence of more clinical data, however, people should not routinely rely on precoital use of LNG-EC to prevent pregnancy unless modern, effective contraceptives are inaccessible to them.

Implications

Based on mathematical modeling, individuals who anticipate needing to take LNG-EC for an impending unprotected act of sex could further reduce their chance of an undesired pregnancy by taking it a few hours in advance.

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.

Gene Expression Changes in the Ovary Mediate Non-Anovulatory Mechanisms of Contraception with Levonorgestrel

BACKGROUND

Emergency contraception with levonorgestrel (LNG) is a viable option to prevent unintended pregnancies. Although the efficacy of LNG as an anovulatory agent decreases as treatment approaches ovulation, it still provides some contraceptive benefits.

AIM

To better understand the contraceptive mechanisms of LNG in ovulatory subjects.

METHODS

We conducted a study on Wistar rats that received a single dose of LNG (0.01 or 0.05 mg/kg) on the morning of proestrus before ovulation and evaluated its effects on ovarian gene expression, ovulation, and implantation.

RESULTS

Our findings showed changes in the expression of genes involved in follicular development and oocyte quality. Pregnancy rates - as an indicator of ovulation - and embryo implantation were significantly lower than those in the control group.

CONCLUSIONS

This study suggests that LNG alters regulatory factors in the ovary that are essential for the development of competent fertilizable oocytes, highlighting the non-anovulatory mechanisms by which levonorgestrel may regulate fertility and suggesting that it could be a novel observation that contributes to the understanding of emergency contraception in humans.

Over-the-counter emergency contraception in Italy: ethical reflections and medico-legal issues

Although more than ten years have passed since the marketing of Ulipristal acetate in Europe, emergency contraception remains a complex issue with many scientific, legal, ethical and social implications. The topic is an example of the differences that can exist between scientific evidence, the certainties on which law is based, and social implications. This paper shows the incompleteness of the scientific reconstruction on the effects of emergency hormonal contraceptives and the dangerousness of the decision to alienate the supply of over-the-counter drugs from the general rules of health care. This report shows the incompleteness of the scientific reconstruction on the effects of emergency hormonal contraceptives and the dangerousness of the decision to alienate the supply of over-the-counter drugs from the general rules of health care. Various ethical and medico-legal issues will be addressed, also focusing attention on underage women whose sexual and reproductive health requires not abandoning them, but actually taking charge of them without medicalizing their choices.

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.

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.

Emergency contraception in university students: prevalence of use and knowledge gaps

OBJECTIVE

Investigate prevalence of use and knowledge about emergency contraception (EC) among female university students from two higher education institutions.

METHODS

Cross-sectional study with 1,740 undergraduates in the city of Santa Maria (RS), from May to October 2017. Information was collected in a semi-structured and self-administered 24-question questionnaire. The investigated variables were grouped into sociodemographic characteristics, sexual behavior, and knowledge of EC. Logistic regression was used for univariate and multivariate analysis, considering variables that presented p < 0.05. The model was adjusted using the Hosmer-Lemeshow test.

RESULTS

The prevalence of EC use among undergraduates was 52.9%. However, only 11.9% of respondents received guidance on EC, especially on how to use it. Only 0.2% of the participants marked 120 hours as the maximum time of use, and 25.7% considered the EC to be abortive. EC use was associated with the age of first sexual intercourse.

CONCLUSION

EC use had a high prevalence among female university students, however, several gaps in method knowledge still exists and it demonstrates the importance of discussing this issue earlier and planning actions of an informative nature.

Case of rupture ectopic pregnancy with emergency contraception levonorgestrel 0.075 mg in a lactating woman

Levonorgestrel emergency contraception (LNG-EC) tends to make uterus unfavorable for implantation but does not prevent embryo implantation. Emergency contraceptives pills should be used with caution among lactating women who at the same time should be monitored closely for ectopic pregnancy.

"It prevents a fertilized egg from attaching…and causes a miscarriage of the baby": A qualitative assessment of how people understand the mechanism of action of emergency contraceptive pills

OBJECTIVE

The mechanism of action (MOA) of emergency contraceptive pills (ECPs) is frequently mischaracterized. Our objective was to identify how members of the general public understand the mechanisms of ECPs.

STUDY DESIGN

We recruited a convenience sample from social media for a survey about reproductive health attitudes and analyzed spontaneous descriptions of how ECPs work. We inductively coded responses to create themes and subthemes, and collapsed subthemes into three MOA categories based on previous research.

RESULTS

Among 1443 respondents, 533 mentioned an MOA in their description of ECPs. While nearly half of these responses (49.5%) stated that ECPs prevent pregnancy before fertilization occurs (in accordance with most biomedical ECP research), over 60% described a mechanism related to preventing implantation of a fertilized egg. Nine percent of responses described a postimplantation mechanism that would be considered abortion by mainstream medical standards. Some respondents conveyed significant confusion about the biological processes involved with pregnancy and pregnancy prevention.

CONCLUSION

Confusion about how ECPs work was common among our sample. The largest group of responses described a mechanism-preventing implantation of a fertilized egg-listed on the Food and Drug Administration (FDA)-approved ECP labels that does not reflect most relevant biomedical research. Mischaracterizations of ECPs' mechanisms have been used to limit access to EC. These misunderstandings were common in our sample and may reflect poor quality sex education and public information, and confusion introduced by the FDA-approved labels. Additional research should identify whether public perception of ECPs' mechanisms influences policy, health care provision, and use of ECPs.

Young women's fertility knowledge: partial knowledge and implications for contraceptive risk-taking

BACKGROUND

There is a lack of research on young women's fertility knowledge and awareness. This has implications for contraceptive risk-taking, including the use of emergency hormonal contraception (EHC). By drawing on two research studies, this article shows how greater fertility knowledge could benefit young women in terms of pregnancy prevention.

METHODS

We draw on two qualitative research studies ('fertility study' and 'abortion study') resulting in a composite sample of 46 interviews with women aged 16-24 years. Focused secondary analysis was undertaken looking specifically at fertility knowledge in relation to contraceptive behaviour.

FINDINGS

A lack of accurate knowledge about the menstrual cycle was evident in two ways. Young women drew conclusions about their invulnerability to pregnancy if previous unprotected sexual intercourse (UPSI) had not resulted in pregnancy. Additionally, although participants were aware of EHC, there was no awareness of when it might fail other than after a certain time limit.

CONCLUSIONS

Young women would benefit from a more nuanced understanding of fertility. Episodes of UPSI that do not result in pregnancy can encourage a belief that 'it won't happen to me', and this has implications for taking chances with contraception. Partial knowledge about the effectiveness of EHC may also lead to unintended pregnancy. Calculating the number of hours following UPSI generates overreliance on what is only one of the factors determining the effectiveness of EHC. Information regarding the link between EHC and failure rates near the day of ovulation needs to be more widely publicised.

"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.

Levonorgestrel emergency contraception and bodyweight

Objectives: Emergency contraception (EC) provides an opportunity to avoid an unwanted pregnancy following unprotected sexual intercourse (UPSI), failure of a regular contraceptive method, or after sexual assault. Two main methods are currently available: oral pills or the copper-T intrauterine device. In recent years there has been some debate regarding the efficacy of oral therapy in obese women. In this brief commentary we review new evidence, published after the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) referral of 2014, relating to the effect of obesity on the pharmacokinetics and clinical efficacy of levonorgestrel EC in light of some of the concerns that have been raised. Methods: A PubMed literature search ("levonorgestrel" and "emergency contraception") was conducted between 1 January 2005 to 31 March 2018; results from the main clinical trials are discussed. Additional literature known to the authors and identified from the reference lists of cited publications was included. Results: Overall, it should be noted that, in studies which determined pregnancy rates across different weight or BMI categories, the overall pregnancy rate was low (1-2%) and there was no direct evidence that lower levonorgestrel plasma levels contributed to an increased pregnancy rate in obese women. This conclusion was reached by the EMA referral in 2014 and they concluded that emergency contraceptive pills (ECPs) could be taken regardless of body weight or BMI, as soon as possible after UPSI. Since the EMA review, additional evidence has been published regarding this topic. This includes PK data (which can neither support, nor deny the previously submitted meta-analyses during the Article 31 Referral procedure), or re-analyses of the previously submitted data. Conclusions: Evidence published since the EMA referral in 2014 does not change the original conclusions of the agency, which recommended that ECPs could be taken regardless of body weight or BMI, as soon as possible after UPSI.

Use of Short Acting Reversible Contraception in Adolescents: The Pill, Patch, Ring and Emergency Contraception

Long acting reversible contraception (LARC) is the recommend form of birth control for adolescents by both the American Academy of Pediatrics and the American Congress of Obstetrics and Gynecology, but the majority of adolescents continue to use short acting reversible contraception (SARC) such as the oral contraceptive pill, vaginal ring, and transdermal patch. For this reason, it is important for medical providers to be familiar with how to prescribe and manage SARC in adolescents, paying particular attention to which patients are eligible to use them, which benefits the methods have outside of contraception, what side effects to be aware of, and special considerations for adolescents. Many adolescents will choose not to use any form of hormonal contraception-thus having a knowledge about and comfort with use of emergency contraception is of equal importance.

Clinical Pharmacology of Hormonal Emergency Contraceptive Pills

Emergency contraceptives play a major role in preventing unwanted pregnancy. The use of emergency contraceptives is characterized by myths and lack of knowledge by both health professionals and users. The main objective of this paper is to summarize the clinical pharmacology of hormonal methods of emergency contraception. A literature review was done to describe in detail the mechanism of action, efficacy, pharmacokinetics, safety profile, and drug interactions of hormonal emergency contraceptive pills. This information is useful to healthcare professionals and users to fully understand how hormonal emergency contraceptive methods work.

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.

The effects of levonorgestrel on FSH-stimulated primary rat granulosa cell cultures through gene expression profiling are associated to hormone and folliculogenesis processes

Levonorgestrel (LNG), a synthetic progestin, is used in emergency contraception (EC). The mechanism is preventing or delaying ovulation at the level of the hypothalamic pituitary unit; however, little knowledge exists on LNG effects at the ovary. The aim of this study was to identify the effects of LNG on FSH-induced 17β-estradiol (E₂) production, including LNG-mediated changes on global gene expression in rat granulosa cells (GC). Isolated GC from female Wistar rats were incubated in vitro in the presence or absence of human FSH and progestins. At the end of incubations, culture media and cells were collected for E₂ and mRNA quantitation. The results showed the ability of LNG to inhibit both hFSH-induced E₂ production and aromatase gene expression. Microarray analysis revealed that LNG treatment affects GC functionality particularly that related to folliculogenesis and steroid metabolism. These results may offer additional evidence for the mechanisms of action of LNG as EC.

"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.

Effect of BMI and body weight on pregnancy rates with LNG as emergency contraception: analysis of four WHO HRP studies

Objective

To estimate the effect of increased body weight and body mass index (BMI) on pregnancy rates with levonorgestrel (LNG) 1.5 mg used as emergency contraception (EC).

Methods

The study reviewed data from 6873 women in four WHO-HRP randomized trials on EC conducted between 1993 and 2010. Participants took either 1.5 mg of LNG as a single dose or in two doses 12 h apart, up to 120 h of unprotected intercourse. Contraceptive efficacy (pregnancy rates) at different weight and BMI categories was evaluated.

Results

Overall pregnancy rate was low at 1.2%. Pregnancy rates were also low in women weighing over 80 kg (0.7%) and who were obese (BMI over 30 kg/m²) (2.0%). The pooled analyses for pregnancy demonstrated that BMI over 30 kg/m² decreased efficacy significantly (odds ratio 8.27, 95% confidence interval = 2.70–25.37) when compared to women in lower BMI categories, mainly influenced by pregnancies in obese women from one study site. Sensitivity analyses excluding that site showed that obesity was no longer a risk factor; however, the other studies included too few obese women in the sample to exclude a substantial decrease in efficacy.

Conclusions

Pregnancy rates with use of LNG 1.5 mg for EC were low at less than 3% across different weight and BMI categories. Pooled analyses showed an increase in pregnancy rates among obese women (BMI more than 30 kg/m²) compared to women with normal BMI levels, influenced by pregnancies all coming from one study site.

Implications

Access to LNG as EC should still be promoted to women who need them, and not be restricted in any weight or BMI category, with additional attention for counselling and advice for obese women.

Emergency Contraception

Emergency contraception (EC) may help prevent pregnancy in various circumstances, such as contraceptive method failure, unprotected sexual intercourse, or sexual assault, yet it remains underused. There are 4 approved EC options in the United States. Although ulipristal acetate requires a provider's prescription, oral levonorgestrel (LNG) is available over the counter for women of all ages. The most effective method of EC is the copper intrauterine device, which can be left in place for up to 10 years for efficacious, cost-effective, hormone-free, and convenient long-term primary contraception. Ulipristal acetate tends to be more efficacious in pregnancy prevention than is LNG, especially when taken later than 72 hours postcoitus. The mechanism of action of oral EC is delay of ovulation, and current evidence reveals that it is ineffective postovulation. Women who weigh more than 75 kg or have a body mass index greater than 25 kg/m(2) may have a higher risk of unintended pregnancy when using oral LNG EC; therefore, ulipristal acetate or copper intrauterine devices are preferable in this setting. Providers are often unaware of the range of EC options or are unsure of how to counsel patients regarding the access and use of EC. This article critically reviews current EC literature, summarizes recommendations, and provides guidance for counseling women about EC. Useful tips for health care providers are provided, with a focus on special populations, including breast-feeding women and those transitioning to long-term contraception after EC use. When treating women of reproductive age, clinicians should be prepared to counsel them about EC options, provide EC appropriately, and, if needed, refer for EC in a timely manner.

Simultaneous determination of levonorgestrel and two endogenous sex hormones in human plasma based on LC-MS/MS

BACKGROUND

Levonorgestrel (LNG) is a commonly used emergency contraceptive which can effect sex hormone levels in female blood. The objective of this study was to develop and validate a specific and sensitive LC-MS/MS method for monitoring endogenous sex hormone levels (17β-estradiol and progesterone) in female plasma after administration of LNG. Results & methodology: The method was developed, optimized and validated according to the EMA guideline. Assay validation met all the criteria, including good linearity in the range of 0.1-20 ng/ml for 17β-estradiol, as well as 0.2-30 ng/ml for LNG and progesterone.

CONCLUSION

The method has been preliminarily applied to explore the variation trend of sex hormone levels in healthy Chinese female volunteers' plasma after oral administration of 1.5 mg LNG tablet. With LNG absorption into plasma, progesterone and estradiol levels descended rapidly, and maintained at low levels in the onset time.

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.

Emergency contraception: Knowledge and practice among women and the spouses seeking termination of pregnancy

BACKGROUND

India was one of the first countries to launch a formal family planning program. Initially, the main thrust of the program was on sterilization but subsequently it has got evolved and now the stress is to bring about awareness of contraception and make informed choices. Emergency contraception has been included in its armamentarium. This study was conducted to find out about the awareness among the cases who report for induced abortion.

METHODS

A total of 784 willing cases were enrolled in the study; there were no exclusion criteria except unwillingness. A parallel group was also included consisting of their spouses. Information that was being sought about Emergency Contraception (EC) included its knowledge, details of administration, and availability.

RESULTS

Of the 784 cases, a large number, 742 (94.6%), underwent first trimester abortion and only 42 (5.3%) underwent second trimester abortion. 286 (36.4%) patients had not used any contraceptive. A large number had used natural methods (35.3%), like lactation, abstinence, or coitus interruptus, and 25.7% had used barrier contraception inconsistently. A very small percentage in both the groups knew about EC; more number of men knew about EC than women.

CONCLUSION

Awareness about emergency contraception is low, as reported in many other studies, though it is available for many years. Awareness about contraceptives needs to be improved and emergency contraceptive should be advocated as a backup method. More efforts are required to generate awareness about regular use of effective contraception and emergency contraception if required.

The regulatory cliff edge between contraception and abortion: the legal and moral significance of implantation

In regulating the voluntary interruption of pregnancy, English law has accorded particular significance to two biological events. First, 'viability', the moment when a fetus is said to acquire the capacity for independent life, plays an important role in grounding restrictions on access to legal abortion later in pregnancy. Second, equally significantly but far less frequently discussed, 'implantation' marks the point in pregnancy from which abortion laws apply. This paper focuses on this earlier biological event. It suggests that an unquestioning reliance on implantation as marking an appropriate moment of transition between two radically different legal frameworks is deeply problematic and is rendered still less sustainable in the light of the development of new technologies that potentially operate shortly after the moment of implantation.

Embracing post-fertilisation methods of family planning: a call to action

Family planning methods that act when administered after fertilisation would have substantial benefits: they could be used longer after sex than current emergency contraceptives, and potentially a woman could use them only on relatively rare occasions when her menstrual period is delayed. Although such methods would displease abortion opponents, they would likely be welcomed by many women. Research to develop post-fertilisation fertility control agents should be pursued.

Practical Advice for Emergency IUD Contraception in Young Women

Too few women are aware of the very high efficacy of intrauterine copper devices (IUDs) to prevent pregnancy after unprotected intercourse. Women who frequently engage in unprotected intercourse or seek emergency contraception (EC) are at high risk of unplanned pregnancy and possible abortion. It is therefore important that these women receive precise and accurate information about intrauterine devices as they may benefit from using an IUD for EC as continuing contraception. Copper IUDs should be used as first choice options given their rapid onset of action and their long-term contraceptive action which require minimal thought or intervention on the part of the user. In the United States, there is only one copper IUD presently available which limits treatment options. There are numerous copper IUDs available for use in EC, however, their designs and size are not always optimal for use in nulliparous women or women with smaller or narrower uteruses. Utilization of frameless IUDs which do not require a larger transverse arm for uterine retention may have distinct advantages, particularly in young women, as they will be suitable for use in all women irrespective of uterine size. This paper provides practical information on EC use with emphasis on the use of the frameless IUD.

Effective dual method contraceptive use and HPV vaccination among U.S. adolescent and young adult females

BACKGROUND

Problem Behavior Theory posits that risky behaviors cluster in individuals, implying that protective behaviors may follow a similar pattern. The purpose of this study was to determine whether the protective behavior of effective dual method contraception use at first and most recent sexual intercourse is associated with HPV vaccination among adolescent and young adult females.

METHODS

National Survey of Family Growth (2006-2010) data were used to examine the association between women's contraception use during first and most recent sexual intercourse and HPV vaccination. Women aged 15 to 24 years (n = 1,820) served as the study sample.

FINDINGS

At first and last sexual intercourse, effective dual method contraception use was reported by 15.3% and 16.8% women, respectively; 27.8% reported receiving at least one dose of the human papillomavirus (HPV) vaccine. Higher HPV vaccination rates were observed among dual method users at first and last sexual intercourse (36.4% and 48.2%, respectively). This trend was also observed across age groups (15-19 year olds vs. 20-24 year olds). In adjusted models, among all respondents, dual users at last sexual intercourse were significantly more likely to be vaccinated, whereas at first sexual intercourse only younger dual users were more likely to report HPV vaccination.

CONCLUSIONS

Findings suggest that the protective behavior of dual method contraceptive use at first and most recent sexual intercourse may serve as a predictor of another complementary health behavior, HPV vaccination, particularly among adolescent females. More research is needed to understand behavioral clustering to design related multi-focused women's health interventions.

Mechanism of action of levonorgestrel emergency contraception

There has been much debate regarding levonorgestrel emergency contraception's (LNG-EC's) method of action since 1999 when the Food and Drug Administration first approved its use. Proponents of LNG-EC have argued that they have moral certitude that LNG-EC works via a non-abortifacient mechanism of action, and claim that all the major scientific and medical data consistently support this hypothesis. However, newer medical data serve to undermine the consistency of the non-abortifacient hypothesis and instead support the hypothesis that preovulatory administration of LNG-EC has significant potential to work via abortion. The implications of the newer data have important ramifications for medical personnel, patients, and both Catholic and non-Catholic emergency room protocols. In the future, technology such as the use of early pregnancy factor may have the potential to quantify how frequently preovulatory LNG-EC works via abortion. Lay Summary: How Plan B (levonorgestrel emergency contraception) works has been vigorously debated ever since the Food and Drug Administration approved it in 1999. Many doctors and researchers claim that it has either no-or at most-an extremely small chance of working via abortion. However, the latest scientific and medical evidence now demonstrates that levonorgestrel emergency contraception theoretically works via abortion quite often. The implications of the newer data have important ramifications for medical personnel, patients, and both Catholic and non-Catholic emergency room rape protocols.

Mainstreaming of emergency contraception pill in India: challenges and opportunities

BACKGROUND

Emergency Contraception Pill (ECP) is an essential intervention to prevent unwanted pregnancies. However, its use has remained low due to various barriers including reservations among medical fraternity.

MATERIALS AND METHODS

This paper presents findings on barriers to ECP's easy access for potential users from (i) a cross-sectional survey of providers' attitudes, beliefs, and practices and interviews with key opinion leaders, (ii) three consultations organized by Population Council with policymakers and public health experts, and (iii) evidence from scientific literature.

RESULTS

The major barriers to easy access of ECP include misconceptions and reservations of providers (disapproval of ECP provision by CHWs, opposition to its being an OTC product, and myths, misconceptions, and moral judgments about its users) including influential gynecologists.

CONCLUSION

For mainstreaming ECP, the paper recommends educational campaign focusing on gynecologists and CHWs, relaxing restrictive policy on advertisement of ECP, involving press media and strengthening supply chain to ensure its regular supply to ASHA (CHW).

Emergency contraception review: evidence-based recommendations for clinicians

Several options for emergency contraception are available in the United States. This article describes each method, including efficacy, mode of action, safety, side effect profile, and availability. The most effective emergency contraceptive is the copper intrauterine device (IUD), followed by ulipristal acetate and levonorgestrel pills. Levonorgestrel is available for sale without restrictions, whereas ulipristal acetate is available with prescription only, and the copper IUD must be inserted by a clinician. Although EC pills have not been shown to reduce pregnancy or abortion rates at the population level, they are an important option for individual women seeking to prevent pregnancy after sex.

Effect of body weight and BMI on the efficacy of levonorgestrel emergency contraception

OBJECTIVES

To further evaluate the effect of weight and body mass index (BMI) on the efficacy of levonorgestrel emergency contraception.

METHODS

Data from two large, multicenter, randomized controlled trials designed to assess emergency contraceptive efficacy were pooled to evaluate the effect of weight and BMI on pregnancy rates among women who received levonorgestrel. Descriptive methods (comparison of means and distributions according to pregnancy status and pregnancy rates across weight and BMI categories) as well as cubic spline modeling were used to describe the relationship between pregnancy risk and weight/BMI.

RESULTS

The analysis population comprised 1731 women, among whom 38 pregnancies were reported. Women for whom levonorgestrel was not effective in preventing pregnancy had a significantly higher mean body weight and BMI than women who did not become pregnant (76.7 vs. 66.4 kg, p<.0001; 28.1 vs. 24.6 kg/m², p<.0001). The estimated pregnancy rate increased significantly from 1.4% [95% confidence interval (CI): 0.5%-3.0%] among the group of women weighing 65-75 kg to 6.4% (95% CI: 3.1%-11.5%) and 5.7% (95% CI: 2.9%-10.0%) in the 75-85 kg and >85 kg groups, respectively. Statistical modeling demonstrated a steep increase in pregnancy risk starting from a weight near 70-75 kg to reach a risk of pregnancy of 6% or greater around 80 kg. Similar results were obtained for statistical modeling of BMI as well as when the two studies were analyzed individually.

CONCLUSIONS

All analyses showed a significant drop in the efficacy of levonorgestrel emergency contraception with increasing body weight, with pregnancy risk in the higher weight categories similar to expected rates in the absence of contraception. Like body weight, increasing BMI was highly correlated with increased pregnancy risk.

Physical and mental development of children after levonorgestrel emergency contraception exposure: a follow-up prospective cohort study

Levonorgestrel (LNG), a dedicated emergency contraception (EC) product, has been available over-the-counter in China for more than 14 yr. Although LNG-EC is considered to have no effects on the developing fetus if the contraceptive fails and pregnancy occurs, there have been a few studies specifically examining this issue. The purpose of this study was to compare the physical and mental development of children born after LNG-EC failure with that of a cohort of children born to mothers with no history of exposure to LNG or any teratogenic substances. A group of 195 children who were exposed to LNG-EC during their mothers' conception cycle (study group) were matched to a group of 214 children without exposure to LNG (control group). The physical and mental development of the children were evaluated and compared over a 2-yr period. There were four congenital malformations in the study group and three in the control group (2.1% vs. 1.4%, respectively, P > 0.05). Over the 2-yr follow-up period, there were no statistically significant differences between the two groups with respect to children's weight, height, head circumference, and intelligence scores, and the values of all parameters of both groups were similar to those of the national standards. In summary, LNG-EC has no effect on the physical growth, mental development, or occurrence of birth defects in children born from pregnancies in which EC failed.

The copper intrauterine device for emergency contraception: an opportunity to provide the optimal emergency contraception method and transition to highly effective contraception

Worldwide, 40% of all pregnancies are unintended. Widespread, over-the-counter availability of oral emergency contraception (EC) has not reduced unintended pregnancy rates. The EC visit presents an opportunity to initiate a highly effective method of contraception in a population at high risk of unintended pregnancy who are actively seeking to avoid pregnancy. The copper intrauterine device (IUD), the most effective method of EC, continues to provide contraception as effective as sterilization for up to 12 years, and it should be offered as the first-line method of EC wherever possible. Increased demand for and supply of the copper IUD for EC may have an important role in reducing rates of unintended pregnancy. The EC visit should include access to the copper IUD as optimal care but should ideally include access to all highly effective methods of contraception.

Ulipristal acetate prevents ovulation more effectively than levonorgestrel: analysis of pooled data from three randomized trials of emergency contraception regimens

BACKGROUND

The days just prior to ovulation are the most crucial for emergency contraception (EC) efficacy. Ulipristal acetate (UPA) and levonorgestrel's (LNG) capacity to inhibit follicular rupture have never been compared directly at this time of the cycle.

STUDY DESIGN

Raw data from three pharmacodynamics studies with similar methodology were pooled to allow direct comparison of UPA, LNG and LNG + meloxicam's ability to prevent ovulation when administered orally in the advanced follicular phase, with a leading follicle of ≥ 18 mm.

RESULTS

Forty eight LNG-treated (1.5 mg) cycles, 31 LNG (1.5 mg) + meloxicam (15 mg), 34 UPA (30 mg) cycles and 50 placebo cycles were compared. Follicle rupture was delayed for at least 5 days in 14.6%, 38.7%, 58.8% and 4% of the LNG-, LNG + meloxicam-, UPA- and placebo-treated cycles, respectively. UPA was more effective than LNG and placebo in inhibiting follicular rupture (p = .0001), while LNG, when administered at this time of the cycle, was not different than placebo. The addition of meloxicam improved the efficacy of LNG in preventing follicular rupture (p = .0292 vs. LNG; p = .0001 vs. placebo; non-significant vs. UPA). UPA was effective in preventing rupture in the 5 days following treatment, even when administered at the time of the luteinizing hormone (LH) surge (UPA 79%, LNG 14% and placebo 10%). None of the treatments were effective when administered on the day of the LH peak. The median time from treatment to rupture was 6 days during the ulipristal cycles and 2 days in the placebo and LNG/LNG + meloxicam cycles (p = .0015).

CONCLUSION

Although no EC treatment is 100% effective in inhibiting follicular rupture when administered in the late follicular phase, UPA is the most effective treatment, delaying ovulation for at least 5 days in 59% of the cycles. LNG is not different from placebo in inhibiting follicular rupture at this advanced phase of the cycle. No treatment was effective in postponing rupture when administered on the day of LH peak.