Emergency contraception: potential role of ulipristal acetate

Progestagens and progesterone receptor modulation: Effects on the brain, mood, stress, and cognition in females

Progesterone is a highly lipophilic gonadal hormone that can influence behavior and mental health through its receptors in the brain. Fluctuations in progesterone levels across critical periods of a females life are associated with increased susceptibility to mental conditions. This review highlights the effects of progestagens, including progesterone and synthetic progestins, on the brain, mood, stress, and cognition in females. The primary focus is on experimental pharmacological research that teases out the distinct effects of progestagens from those of estrogens. Additionally, the key literature on puberty, the menstrual cycle, pregnancy, perimenopause, hormonal contraceptives, and menopausal hormone therapy is reviewed, although conclusions are limited by the nested effects of progestagens and estrogens. Single study-findings suggest an influence of progesterone on amygdala reactivity related to processing of emotional stimuli and memory. In patients with premenstrual dysphoric disorder, progesterone receptor modulation improves premenstrual mood symptoms and potentially enhances fronto-cingulate control over emotion processing. The interaction between progestagens and the systems involved in the regulation of stress seems to influence subjective experiences of mood and stress. Sparse studies investigating the effects of progestin-only contraceptives suggest effects of progestagens on the brain, mood, and stress. Progesterone and progestins used for contraception can influence neural processes as myelination and neuroprotection, exerting protective effects against stroke. Concerning menopausal hormonal therapy, the effects of progestins are largely unknown. Levels of progesterone as well as type, administration route, timing, dose regimen, metabolism, and intracellular activity of progestins in hormonal contraceptives and menopausal hormonal therapy are factors whose effects remain to be elucidated. Altogether, current knowledge highlights the potential role of progestagens in females health but also calls for well-designed pharmaco-behavioral studies disentangling the effects of progestagens from those of estrogens.

In Vitro Human Endometrial Cells and In Vivo Rat Model Studies Suggest That Ulipristal Acetate Impacts Endometrial Compatibility for Embryo Implantation

BACKGROUND

Ulipristal acetate (UPA) and levonorgestrel are used as emergency hormonal contraceptives. Although both are highly effective in preventing pregnancy, UPA shows efficacy even when taken up to 120 h after unprotected sexual intercourse.

AIMS

To investigate whether the mechanism of UPA's contraceptive action involves post-fertilization effects.

METHODS

In vitro and in vivo studies using cultured human endometrial cells and a pre-clinical rat model.

RESULTS

Endometrial cells treated with UPA showed changes in the expression of receptivity gene markers and a significant decrease in trophoblast spheroids attached to the cultured cells. In addition, administration of UPA to female unmated rats decreased the expression of implantation-related genes in the endometrium and inhibited the number of implantation sites in the mated group compared to the non-treated group.

CONCLUSIONS

These results support that UPA as an emergency contraceptive might have post-fertilization effects that may affect embryo implantation.

Current and Emerging Treatment Options for Uterine Fibroids

Uterine fibroids are the most common benign neoplasm of the female reproductive tract in reproductive age women. Their prevalence is age dependent and can be detected in up to 80% of women by the age of 50 years. Patients affected by uterine fibroids may experience a significant physical, emotional, social, and financial toll as well as losses in their quality of life. Unfortunately, curative hysterectomy abolishes future pregnancy potential, while uterine-sparing surgical and radiologic alternatives are variously associated with reduced long-term reproductive function and/or high tumor recurrence rates. Recently, pharmacological treatment against uterine fibroids have been widely considered by patients to limit uterine fibroid-associated symptoms such as heavy menstrual bleeding. This hormonal therapy seemed effective through blocking the stimulatory effects of gonadal steroid hormones on uterine fibroid growth. However, they are contraindicated in women actively pursuing pregnancy and otherwise effective only during use, which is limited because of long-term safety and other concerns. Accordingly, there is an urgent unmet need for safe, durable, and fertility-compatible non-surgical treatment options for uterine fibroids. In this review article, we cover the current pharmacological treatments for uterine fibroids including their comparable efficacy and side effects as well as emerging safe natural compounds with promising anti-uterine fibroid effects.

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.

Effect of ulipristal acetate on gene expression profile in endometrial cells in culture and in vivo upon post-ovulatory administration in fertile women

PURPOSE

To analyse the effect of ulipristal acetate (UPA) as emergency contraception (EC) on the gene expression of human endometrial cell line (HEC-1A) and endometrium from fertile women treated with UPA after ovulation.

MATERIALS AND METHODS

HEC-1A cells were treated with UPA, and endometrial tissue from four healthy women was collected in cycles before, during and 2 months after post-ovulation pill intake. Ovulation and luteal phase were monitored, and endometrial biopsies were obtained at day LH + 7 in each cycle. In all cases, we analysed the expression profile of 192 genes associated to endometrial receptivity.

RESULTS

We observed a significant change in total transcriptomic activity of UPA-treated HEC-1A cells compared to controls. In vivo, we also observed a trend to down-regulation of genes in the UPA-treated cycle that was partially restored in the post-treatment cycle. Altogether, our results supported a partially reversible effect of UPA in gene expression associated with uterine receptivity.

CONCLUSIONS

When UPA was administered after ovulation, it seems to induce a down-regulation of the main genes involved in conditioning the endometrium for implantation. This effect is partially restored two months after pill intake. The action of UPA on the endometrium for users of EC should be further investigated.

Targeting progesterone signaling prevents metastatic ovarian cancer

Effective cancer prevention requires the discovery and intervention of a factor critical to cancer development. Here we show that ovarian progesterone is a crucial endogenous factor inducing the development of primary tumors progressing to metastatic ovarian cancer in a mouse model of high-grade serous carcinoma (HGSC), the most common and deadliest ovarian cancer type. Blocking progesterone signaling by the pharmacologic inhibitor mifepristone or by genetic deletion of the progesterone receptor (PR) effectively suppressed HGSC development and its peritoneal metastases. Strikingly, mifepristone treatment profoundly improved mouse survival (∼18 human years). Hence, targeting progesterone/PR signaling could offer an effective chemopreventive strategy, particularly in high-risk populations of women carrying a deleterious mutation in the BRCA gene.

The Selective Progesterone Receptor Modulator Ulipristal Acetate Inhibits the Activity of the Glucocorticoid Receptor

CONTEXT

The selective progesterone modulator ulipristal acetate (ulipristal) offers a much-needed therapeutic option for the clinical management of uterine fibroids. Although ulipristal initially passed safety evaluations in Europe, postmarketing analysis identified cases of hepatic injury and failure, leading to restrictions on the long-term use of ulipristal. One of the factors potentially contributing to significant side effects with the selective progesterone modulators is cross-reactivity with other steroid receptors.

OBJECTIVE

To determine whether ulipristal can alter the activity of the endogenous glucocorticoid receptor (GR) in relevant cell types.

DESIGN

Immortalized human uterine fibroid cells (UtLM) and hepatocytes (HepG2) were treated with the synthetic glucocorticoid dexamethasone and/or ulipristal. Primary uterine fibroid tissue was isolated from patients undergoing elective gynecological surgery and treated ex vivo with dexamethasone and/or ulipristal. In vivo ulipristal exposure was performed in C57Bl/6 mice to measure the effect on basal gene expression in target tissues throughout the body.

RESULTS

Dexamethasone induced the expression of established glucocorticoid-target genes period 1 (PER1), FK506 binding protein 51 (FKBP5), and glucocorticoid-induced leucine zipper (GILZ) in UtLM and HepG2 cells, whereas cotreatment with ulipristal blocked the transcriptional response to glucocorticoids in a dose-dependent manner. Ulipristal inhibited glucocorticoid-mediated phosphorylation, nuclear translocation, and DNA interactions of GR. Glucocorticoid stimulation of PER1, FKBP5, and GILZ was abolished by cotreatment with ulipristal in primary uterine fibroid tissue. The expression of glucocorticoid-responsive genes was decreased in the lung, liver, and uterus of mice exposed to 2 mg/kg ulipristal. Interestingly, transcript levels of Fkbp5 and Gilz were increased in the hippocampus and pituitary.

CONCLUSIONS

These studies demonstrate that ulipristal inhibits endogenous glucocorticoid signaling in human fibroid and liver cells, which is an important consideration for its use as a long-term therapeutic agent.

Selective progesterone receptor modulators for fertility preservation in women with symptomatic uterine fibroids

Uterine fibroids (UFs, AKA leiomyoma) are the most important benign neoplastic threat to women's health, with costs up to hundreds of billions of health care dollars worldwide. Uterine fibroids caused morbidities exert a tremendous health toll, impacting the quality of life of women of all ethnicities, especially women of color. Clinical presentations include heavy vaginal bleeding, pelvic pain, bulk symptoms, subfertility, and obstetric complications. Current management strategies heavily lean toward surgical procedures; nonetheless, the choice of treatment is generally subject to patient's age and her desire to preserve future fertility. Women with UF who desire to maintain future fertility potential face a dilemma because of the limited treatment choices that are currently available to help them achieve that goal. Recently, ulipristal acetate the first of the promising family of oral selective progesterone receptor modulators has been approved for UF treatment in Europe, Canada, and several other countries and is under review for possible approval in the USA. In this review article, we discuss recent advances in the management options against UF with a bend toward oral effective long-term treatment alternatives who are particularly suited for those seeking to preserve their future fertility potential. We also explore the transformative concept of primary and secondary UF prevention using these new anti-UF agents. We envision a remarkable shift in the management of UF in future years from surgical/invasive treatment to orally administrated options; clearly, this potential shift will require additional intense clinical research.

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.

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.

Association between knowledge about levonorgestrel emergency contraception and the risk of ectopic pregnancy following levonorgestrel emergency contraception failure: a comparative survey

Objective

To study the association between knowledge about levonorgestrel emergency contraception (LNG‐EC) and the risk of ectopic pregnancy (EP) following LNG‐EC failure.

Methods

This study included 600 women who had visited the hospital with LNG‐EC failure. Of these, 300 with EP and 300 with intrauterine pregnancy (IUP) were recruited to the EP group and IUP group respectively. The participants were interviewed face‐to‐face using a standardized questionnaire.

Main Outcome Measures

Pearson's chi‐square tests and t‐test were used to compare the sociodemographic characteristics, reproductive and gynecological history, surgical history, previous contraceptive experience, and answers to 10 questions concerning the knowledge about LNG‐EC.

Results

Those who gave incorrect answers to the question regarding the basic mechanism and specific method of levonorgestrel emergency contraceptive pills (LNG‐ECPs) were at a higher risk of EP after LNG‐EC failure. Women who did not strictly follow instructions or advice from healthcare professionals were more likely to subsequently experience EP (p < 10⁻⁴). Women with LNG‐EC failure reported friends/peers, TV, and Internet as the main sources of information. No difference was observed with regard to the sources of knowledge on LNG‐EC (p = 0.07).

Conclusions

The results illustrate the importance of strictly following the doctor's guidance or drug instructions when using LNG‐ECPs. The media should be used to disseminate information about responsible EC, and pharmacy staff should receive regular educational training sessions in this regard. © 2016 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons Ltd.

Selective progesterone receptor modulators: an update

INTRODUCTION

Several selective progesterone receptor modulators (SPRMs) show promise in several areas of medicine and this work has been summarized by us in 2008.

AREAS COVERED

Since the publication of our reviews, several developments have taken place in the field of reproductive medicine. The first is emergency contraception (EC). Two SPRMs are clinically utilized today: mifepristone (MFP) and ulipristal acetate (UPA). MFP is available for EC in up to 120 h following unprotected intercourse. A dose of 10 mg is significantly more effective than levonorgestrel (LNG). In a metanalysis of the use of UPA versus LNG up to 72 h after unprotected intercourse, failure rates of 1.4 versus 2.2% were reported. The second is contraception. A daily dose of 2 mg MFP can block ovulation and several MFP regimens are being tested, including a vaginal ring releasing MFP. The third is the preoperative administration in women harboring leiomyomas, where clinical testing of several SPRM has shown that they can decrease uterine leiomyomas' size and substantially reduce uterine bleeding. SPRM can induce unusual, specific endometrial appearances. Many believe that these changes should not cause concern, but the issue remains controversial.

EXPERT OPINION

SPRMs are very effective in EC and for the preoperative treatment of uterine leiomyomas.

Use of ulipristal acetate, levonorgestrel and the copper-intrauterine device for emergency contraception following the introduction of new FSRH guidelines

OBJECTIVES

The UK Faculty of Sexual & Reproductive Healthcare (FSRH) has recommended that for emergency contraception (EC) the health professional should discuss individual needs and inform women of the different methods, efficacy, adverse effects, interactions, eligibility and additional contraception. In our sexual and reproductive health care service (Liverpool and Knowsley, UK), revised guidance was issued in early 2012, reflecting Faculty advice. We studied (1) how our use of EC changed, (2) which methods were offered and how this changed, (3) which method was chosen by women who were offered all three UK licensed methods of EC and (4) the appropriateness of the offer of only levonorgestrel (LNG).

METHODS

We studied a total of 2989 case records in the 3 months before and 3 months following the adoption by our service of the 2011 FSRH guidance. This was a retrospective review of charts undertaken by interrogating our computerised Excelicare(®) system of clinical records. All EC episodes in the two 3-month periods were analysed, covering October-December 2011 and March-May 2012. Additionally, three non-probabilistic, purposeful samples of representative practitioners' charts were examined in groups of women offered all methods [and choosing either ulipristal acetate (UPA) or LNG] or who were offered LNG only.

RESULTS

The use of LNG fell from 93.0% of EC issued to 76.0%; UPA use rose from 3.0% to 18.7%. In the second 3-month period, of the women offered all three methods, 54.9% chose LNG and 39.8% UPA. LNG-only offers in our judgement were clinically appropriate in 62.5% cases of such offers.

CONCLUSIONS

Comparing the second period with the first, more women were offered all three methods, the use of LNG fell (93.0% to 76.0%) and that of UPA increased (3.0% to 18.7%). Women were encouraged to exercise choice. However, increasing choice in our service did not lead to a wholesale change from LNG to UPA.

Emergency contraception

There have been numerous attempts to control fertility after unprotected sexual intercourse (UPSI). From very bizarre methods like the vaginal application of Coca Cola to the more serious attempts using calcium antagonists influencing fertility parameters in sperm to hormonal methods or intrauterine devices. So far, hormonal methods preventing or delaying ovulation have proved to be the most popular starting with the combination of ethinyl estradiol and levonorgestrel (LNG), known as the Yuzpe regimen. The first dose had to be taken within 72 hours of UPSI, a second one 12 hours later. Later on, LNG alone, at first in a regimen similar to the Yuzpe method (2 × 0.75 mg 12 hours apart) showed to be more successful, eventually resulting in the development of a 1.5 mg LNG pill that combined good efficacy with a high ease of use. Several efficacious and easy to use methods for emergency contraception (EC) are available on the market today with the most widely spread being LNG in a single dose of 1.5 mg (given as one tablet of 1.5 mg or 2 tablets of 0.75 mg each) for administration up to 3 days (according to WHO up to 5 days) after UPSI. Its limitations are the non-optimal efficacy which is decreasing the later the drug is taken and the fact that it is only approved for up to 72 hours after UPSI. This regimen has no effect on the endometrium, corpus luteum function and implantation, is not abortive and don't harm the fetus if accidentally taken in early pregnancy. It has no impact on the rate of ectopic pregnancies. It has become the standard method used up to this day in most countries. Since the mid 1970s copper IUDs have been used for EC, which show a high efficacy. Their disadvantages lie in the fact that EC is considered an off label use for most IUDs (not for the GynFix copper IUD in the European Union) and that they might not be acceptable for every patient. Furthermore IUD-insertion is an invasive procedure and it is required trained providers and sterilized facilities. Mifepristone in the dosages of 10 or 25 mg is used with good results as an emergency contraceptive in China for up to 120 hours after UPSI, but has never received any significant consideration in Western countries. While high doses of mifepristone has an effect on endometrial receptivity and will inhibit ovulation if given in the follicular phase and prevent implantation if given in the early luteal phase, low doses such as 10 mg has no impact on the endometrium. Mifepristone does not increase the rate of ectopic pregnancies. The most recent development is the approval of the selective progesterone receptor modulator ulipristal acetate (UPA) in the dosage of 30 mg for EC up to 5 days after UPSI, combining the safe and easy application of the single dose LNG pill with an even higher efficacy. It has shown to be more efficacious than LNG and can be used for up to 120 hours after UPSI; the difference in efficacy is highest for 0-24 hours, followed by 0-72 hours following UPSI. No VTE has been reported following UPA-administration or any progesterone receptor modulator. No effect on endometrium, corpus luteum function and implantation has been observed with doses used for EC. Independent of the substance it should be noted that, if there is a choice, the intake of an oral emergency contraceptive pill should happen as soon as possible after the risk situation. A pre-existing pregnancy must be excluded. Possible contraindications and drug interactions must be considered according to the individual special product informations.

Emerging options for emergency contraception

Emergency post-coital contraception (EC) is an effective method of preventing pregnancy when used appropriately. EC has been available since the 1970s, and its availability and use have become widespread. Options for EC are broad and include the copper intrauterine device (IUD) and emergency contraceptive pills such as levonorgestrel, ulipristal acetate, combined oral contraceptive pills (Yuzpe method), and less commonly, mifepristone. Some options are available over-the-counter, while others require provider prescription or placement. There are no absolute contraindications to the use of emergency contraceptive pills, with the exception of ulipristal acetate and mifepristone. This article reviews the mechanisms of action, efficacy, safety, side effects, clinical considerations, and patient preferences with respect to EC usage. The decision of which regimen to use is influenced by local availability, cost, and patient preference.

Ulipristal acetate, a progesterone receptor modulator for emergency contraception

Unwanted pregnancy is a global reproductive health problem. Emergency contraception is defined as the use of drug or device after unprotected or underprotected intercourse to prevent an unwanted pregnancy. 1.5 mg of levonorgestrel as a single dose or in two doses with 12 h apart taken within 72 h of unprotected intercourse is the current gold standard emergency contraception regimen. This method is only effective if used as soon as possible after sexual intercourse and before ovulation. A single dose of 30 mg ulipristal acetate, a novel selective progesterone receptor modulator, has recently been proposed for the emergency contraception use up to 120 h of unprotected intercourse with similar side effect profiles as levonorgestrel. Ulipristal acetate could possibly prevent pregnancy when administered in the advanced follicular phase, even if luteinizing hormone levels have already begun to rise, a time when levonorgestrel is no longer effective in inhibiting ovulation.

Nowadays which emergency contraception? Comparison between past and present: latest news in terms of clinical efficacy, side effects and contraindications

Despite many highly effective methods of contraception are available nowadays, many pregnancies are unintended. Emergency contraception (EC) is the use of drug or device after unprotected intercourse to prevent an unwanted pregnancy. It is a woman's last chance to prevent unintended pregnancy. Nevertheless the confusion about mechanisms of action, side effects, clinical efficacy and controindications makes the intervention underused in every setting investigated. So far levonorgestrel (LNG) has been considered the gold standard for oral EC. Today, a new type of second generation progesterone receptor modulator, ulipristal acetate (UPA) has been proposed as a more effective drug than LNG in prevention of unwanted pregnancies by delaying or inhibiting ovulation; even if many other devices are disposable in commerce. We revised the literature to concern most of the data available on the role of EC and moreover clarifying the available methods, the action windows of the accessible devices, the adverse events and the controindications.

Ulipristal blocks ovulation by inhibiting progesterone receptor-dependent pathways intrinsic to the ovary

Ulipristal acetate (UPA), a progesterone receptor (PR) modulator, is used as an emergency contraceptive in women. Here, using a mouse model, we investigated the mechanism of action of UPA as an ovulation blocker. In mice, ovulation is induced ~12 hours following the treatment with exogenous gonadotropins, including human chorionic gonadotropin (hCG), which mimics the action of luteinizing hormone (LH). When administered within 6 hours of hCG treatment, UPA is a potent blocker of ovulation. However, UPA's effectiveness declined significantly when it was given at 8 hours post hCG. Our study revealed that, when administered within 6 hours of hCG, UPA blocks ovulation by inhibiting PR-dependent pathways intrinsic to the ovary. At 8 hours post hCG, when the PR signaling has already occurred, UPA is unable to block ovulation efficiently. Collectively, these results indicated that UPA, when administered within a critical time window following the LH surge, blocks PR-dependent pathways in the ovary to function as an effective antiovulatory contraceptive.

When can a woman resume or initiate contraception after taking emergency contraceptive pills? A systematic review

BACKGROUND

Hormonal emergency contraception can postpone ovulation, making a woman vulnerable to pregnancy later in the same cycle. However, concern exists as to whether concurrently administered emergency contraception pills (ECP) and other hormonal methods of contraception may affect the effectiveness of both medications.

STUDY DESIGN

A systematic review of the literature using PubMed and the Cochrane databases was performed to identify articles concerning the resumption or initiation of regular contraception within the same cycle as ECP use. We searched for articles in any language, published between 1980 and April 2012 and included all methods of emergency contraception pills available in the USA.

RESULTS

The search strategy identified 184 articles in the PubMed and Cochrane databases, of which none met inclusion criteria.

CONCLUSION

The drug manufacturer advises continuation or initiation of routine contraception as soon as possible after use of ulipristal acetate, with concomitant use of a reliable barrier method until next menses. However, a theoretical concern exists that given ulipristal acetate's function as a selective progesterone receptor modulator, coadministration of a progestin could decrease its effectiveness as an emergency contraceptive. Initiation of hormonal contraception following levonorgestrel or the Yuzpe regimen for emergency contraception carries no similar concern for decreased method effectiveness.

Ulipristal acetate as an emergency contraceptive agent

INTRODUCTION

Emergency contraceptive agents play a crucial role in preventing unplanned pregnancy. These agents and devices have been studied since the 1960s and have had varied results in terms of side effects and efficacy. A new oral tablet for emergency contraception (EC), ulipristal acetate (UPA) , is a selective progesterone receptor modulator and can be used up to 120 h following unprotected intercourse, without an increase in adverse effects or a decrease in efficacy.

AREAS COVERED

This article reviews studies that evaluate the pharmacodynamics, pharmacokinetics, clinical efficacy, and safety profile of UPA as an emergency contraceptive agent.

EXPERT OPINION

UPA, a selective progesterone receptor modulator, is administered as a single 30 mg dose for EC. This agent provides a comparable, if not better, efficacy and side effect profile than seen with levonorgestrel or mifepristone. Because it has both agonistic and antagonistic effects on the progesterone receptor, ongoing clinical trials are documenting UPA's use for patients with endometriosis and as an extended use contraceptive.

The Prescription of the Morning-After Pill in a Berlin Emergency Department Over a Four-Year Period - User Profiles and Reasons for Use

Questions: There are no current health care studies from Germany regarding the "morning-after pill". This paper will use routine data to analyse details regarding the users' profiles, reasons for using it and the utilisation of hospital outpatient facilities. Patient Collective and Methods: Retrospective analysis of all triage sheets in the emergency department of the Virchow Hospital Campus/Charité University Hospital, Berlin, over a four-year period from 2007 to 2010 that were coded with the ICD diagnosis Z30 (= contraception advice) and statistical processing of the associated administrative data. Results: 860 triage sheets were included in the analysis. The emergency department is used most frequently for the prescription of the "morning-after pill" at the weekend. The average age of the users was 25.1 years. The most common reason cited for needing emergency contraception was unprotected sexual intercourse, with the second-most common being "condom failure". Around half of the women attended the department within 12 hours of having unprotected sex. Less than 2 % (n = 14) of all women decided against a prescription of emergency contraceptive after counselling. Conclusions: The user profile and reasons for using emergency oral contraception correlate largely with the information contained in international literature. Although the "morning-after pill" is probably prescribed mainly in general practices in Germany, and despite the availability of new drugs with a permitted post-exposure interval of up to 120 hours after unprotected sex, there appears to still be a high demand for counselling and prescriptions of the "morning-after pill" in the context of the emergency department.

Immunopharmacology of ulipristal as an emergency contraceptive

A new progesterone antagonist, ulipristal has been made available as an emergency contraceptive. Ulipristal’s major mechanism of action as an emergency contraceptive has been ascribed to its ability to delay ovulation beyond the life span of the sperm. This paper analyzes the potential action of ulipristal (1) when unprotected intercourse and administration of ulipristal occur outside the fertility window and (2) when unprotected intercourse and administration of ulipristal occur at or within 24 hours of ovulation. When unprotected intercourse and the use of a single low dose of ulipristal occur outside of the fertility window, ulipristal behaves like a placebo. When unprotected intercourse and the use of a single low dose of ulipristal occur within the fertility window but before ovulation, ulipristal behaves like an emergency contraceptive by delaying ovulation and thereby preventing fertilization. When unprotected intercourse and the administration of ulipristal occur at or within 24 hours of ovulation, then ulipristal has an abortifacient action. It is proposed that the abortifacient mechanism of a low dose of ulipristal taken after fertilization but before implantation is due to the ability of ulipristal to block the maternal innate immune system to become immunotolerant to the paternal allogenic embryo. Progesterone’s critical immunotolerant actions involving early pregnancy factor, progesterone-induced blocking factor, and uterine natural killer cells are compromised by ulipristal.

Ulipristal acetate: a review of its use in emergency contraception

Ulipristal acetate (ellaOne®; ella®) is the first of a new class of selective progesterone receptor modulators, and is indicated for emergency contraception within 120 hours after unprotected sexual intercourse or contraceptive failure. The principal effect of ulipristal acetate is to inhibit or delay ovulation. This effect may result from the drug's ability to delay the onset of luteinizing hormone (LH) surge or postpone LH peak if LH surge has started, or possibly by a direct inhibitory effect on follicular rupture, when administered in the follicular phase (including just before ovulation). In clinical trials, a single oral dose of ulipristal acetate 30 mg was effective in preventing pregnancies in women requesting emergency contraception after unprotected sexual intercourse and provided sustained efficacy throughout the 120-hour postcoital period in which it is indicated. When compared with levonorgestrel in well designed noninferiority trials, it was no less effective in preventing pregnancies when administered within 72 hours of unprotected intercourse, but was more effective when administered later (within 72-120 hours). Results of a meta-analysis suggest that ulipristal acetate may be more effective than levonorgestrel from day 1 and throughout the entire 5-day period following unprotected sexual intercourse. Ulipristal acetate is generally well tolerated, with a similar tolerability profile to that of levonorgestrel. In general, the onset of menses is delayed by 2-3 days following treatment. Although, ulipristal acetate is more expensive than levonorgestrel, it may represent a cost-effective alternative to levonorgestrel for women requesting emergency contraception within 120 hours of unprotected intercourse. Thus, ulipristal acetate provides effective, sustained and well tolerated emergency contraception when taken within 120 hours of unprotected sexual intercourse, thereby offering an extended treatment window compared with levonorgestrel, which should be administered within 72 hours.

Emergency contraception: an updated review

Emergency contraception is a common practice now. Many categories of drugs are marketed with modifications in dosage, in combination and even in the timing of administration. Recent re-analysis suggests that there is still no uniformity of opinion on the actual mechanism of action and this has often fueled the ethical controversy. This review analyzes the most common emergency contraception drugs: levonorgestrel, mifepristone and ulipristal acetate about their action underlining that the hormonal products, when used in emergency contraception, play different roles depending on the phase of the menstrual cycle during which they are administered.This review aims to examine rigorously the most accredited literature to verify if a evidence-based uniformity of opinions has been achieved about the biological effects of hormones administered after the sexual intercourse.

The state-of-the-art of emergency contraception with the cutting edge drug

The objective of this study is to evaluate and elucidated the potential of selective progesterone receptor modulators (SPRMs) to be an effective emergency contraception (EC). The data are extracted from the literature through the MEDLINE database service from 2000-2010. The SPRMs are in fact progesterone receptor ligands that could bind to progesterone receptor (PR) and exert antagonistic, agonistic or mixed agonist-antagonistic effects. These SPRMs are mifepristone, onapristone, asoprisnil, ulipristal, proellex among other compounds. Currently developed SPRMs may exert contraceptive effects by inhibiting ovulation and retarding endometrial synchronization. Low-doses of progesterone antagonists retard endometrial maturation without affecting ovulation. Mifepristone being a SPRM is effective for prevention of pregnancy but with prostaglandin acts as an excellent abortifacient; yet could not compete with levonorgestrel as EC. However, a single dose of 30 mg ulipristal acetate, another SPRM with similar effectiveness and side effect profiles as 1.5 mg levonorgestrel EC, has shown wider 'window of effect' by inhibition of the LH peak even if administered at the advanced pre-ovulatory phase, a time when use of levonorgestrel EC is no longer effective. Thus, ulipristal acetate goes one-step ahead of levonorgestrel in the field of emergency contraception treatment. Further studies are needed to explore the potential of other SPRMs to be cutting edge emergency contraceptive drugs.