In September 2012, in an effort to manage and prevent the most frequent causes of mortality, the United Nations Commission on Life-Saving Commodities for Women and Children described a plan to provide 13 lifesaving, low-cost, and high-impact commodities, including medicines and medical devices that support reproductive, newborn, maternal, and child health. Emergency contraceptive pills were 1 of them.1–5
Emergency contraception (EC) is defined as a drug or device used to prevent pregnancy after intercourse in which a contraceptive was not used or was used incorrectly.6,7 Currently available methods include the copper intrauterine device and hormone-based pills.8 The copper intrauterine device has the highest efficacy,9 resulting in a 0.09% pregnancy rate when insertion occurs within 5 days after intercourse.10 This efficacy rate is 10-times higher than that of oral emergency contraceptives,11 but has the disadvantage of being more invasive.7 Hormonal methods of EC are more convenient7 and, because of the short duration of the regimen, they are not contraindicated even for women who otherwise could not use long-term hormonal contraceptives.
The first hormonal method, the Yuzpe regimen, was introduced in 1977 and consisted of ethinyl estradiol and levonorgestrel (LNG) administered within 72 hours after intercourse and repeated 12 hours later.12,13 It was the least effective method and caused the most adverse effects, such as nausea and vomiting.9,14 Later, the LNG-only regimen emerged as a more effective and a better tolerated option.7,15 Subsequently, ulipristal acetate (UPA) was developed7 and is currently recommended as the first-line treatment.16 Oral LNG and UPA are at this time the 2 hormonal emergency contraceptives approved by the US Food and Drug Administration (FDA).17
LNG, a synthetic steroid,18 is a progestogen that binds the progesterone receptors, and the glucocorticoid and androgen receptors, and inhibits the surge of luteinizing hormone (LH) before ovulation.19–24 LNG was first approved in 1999 as a two-dose prescription-only product of 0.75 mg each, taken 12 hours apart. In August 2006, it was approved over-the-counter for women and men aged 18 years or older,25,26 and in 2009, the nonprescription sale became available for those 17 years and older.27 A one-pill regimen was approved by the FDA in 2013 for over-the-counter sale and without age restrictions, and generic versions became available in 2014.28–31 After April 2016, the two-dose regimen was no longer marketed in the US and only the one-dose 1.5 mg LNG regimen has been available over the counter.32 UPA, a synthetic second generation selective progesterone receptor modulator7 was approved by the FDA in December 20107,33 and is a 30 mg tablet that has to be taken within 120 hours after intercourse.33 It is available by prescription only34 and its efficacy is decreased by medications that lower gastric acidity such as antacids, proton pump inhibitors, or H2 blockers.35,36
LNG is not effective once the LH surge starts to occur9,33 and the sooner after intercourse it is taken, the more effective it is.37–39 In contrast, UPA works even after the LH peak has surged,33 and an analysis of pooled phase 3 studies found that delaying treatment after intercourse did not have a statistically significant effect on preventing a pregnancy.40
An increased Body Mass Index (BMI) decreases the efficacy of LNG and UPA. A meta-analysis of 2 randomized controlled trials found that women with a BMI over 30 kg/m2 had a more than 3-fold higher risk of pregnancy, and women with a BMI between 25 kg/m2 and 30 kg/m2 had a 1.5-fold higher risk of pregnancy than women with a BMI under 25 kg/m2, irrespective of which of the 2 oral EC preparations they used.41 Neither the copper IUD nor the LNG IUD are affected by weight and remain the most effective options for EC.42,43
There are no medical contraindications to either type of oral EC preparation. For IUDs, the same medical eligibility criteria apply for EC as for their non-EC insertion. If the patient has had unprotected intercourse or has been sexually assaulted, testing for sexually transmitted infections should be performed at the time of insertion or they should be treated per protocol.44–49
MECHANISMS OF ACTION
In vitro and in vivo research show that EC acts by 1 or more of several mechanisms of action.50,51
Delaying or inhibiting ovulation
Is believed to be the primary or exclusive mechanism of action for LNG and UPA.52,53 The major distinction between the 2, with respect to their effect on ovulation, is their window of action,16 and their efficiency depends on the time during the ovarian cycle when they are administered.6 LNG can delay or inhibit the mid-cycle LH surge when administered 2–3 days before ovulation and interferes with follicular development, but it does not inhibit ovulation if administered the day of the LH peak or afterward.8,54 When given in the mid-follicular phase, UPA delays, in a dose-dependent manner, the time until follicular rupture and suppresses estradiol, and remains effective even after the LH surge has started.6,55–57 Animal experiments showed that UPA is a powerful inhibitor of ovulation, whether administered before or after the onset of the LH surge.58,59 In a clinical trial, UPA prevented follicular rupture for at least 5 days in 59% of the cycles when the leading follicle was ≥18 mm, and in ∼79% of the cycles if administered after the onset of the LH surge, but before its peak, but only in ∼8% of the cycles when administered after the LH peak.60 Comparatively, LNG prevented follicular rupture in only 12% of the follicles ≥18 mm within 5 days.54 Thus, UPA is effective even when LNG can no longer be used.8 Analyses of data from 3 randomized controlled trials showed that UPA is more effective than LNG in preventing ovulation.61
Effects on oocyte transport
Evidence that EC can interfere with oocyte transport is inconsistent across studies. In rabbits, a single dose of ethinyl estradiol interfered with the transport of the oocytes, which entered the uterus too soon or remained in the fallopian tubes for too long.62 An in vitro experimental study that used fallopian tube samples from women undergoing hysterectomies for benign conditions reported that UPA dose-dependently inhibited the ciliary beating frequency and reduced the frequency and amplitude of the muscular contractions.63 Another study found that UPA antagonized the effects of progesterone on ciliary beating frequency in the human fallopian tubes, where it also upregulated the expression of estrogen receptor α and progesterone receptor.64
Effects on spermatozoa
In some in vitro studies, high LNG concentrations induced the acrosomal reaction in human spermatozoa, but this was not observed at concentrations comparable with the ones achieved in the serum after its use for EC.65–68 A double-blind placebo-controlled study of women receiving 1.5 mg LNG 24 or 48 hours after sexual intercourse or artificial insemination did not see any effects on the acrosomal reaction or on endometrial glycodelin-A expression.69 The ability of LNG to inhibit the velocity of spermatozoa and their fusion with the oocyte was observed only at high concentrations, which are unlikely to be relevant in context of EC regimens.8,70 UPA decreased the number of rabbit spermatozoa arriving to the vicinity of the oocyte, and pretreating capacitated spermatozoa with UPA decreased their abundance around the oocyte–cumulus complex, indicating that they are chemically repelled from the unfertilized oocyte.71 An in vitro study reported that UPA suppresses the progesterone-induced acrosome reaction, hyperactivation, and calcium concentration in the spermatozoa.72 However, an effect on the acrosomal reaction was not observed in other studies, and UPA did not inhibit the acrosomal reaction induced by human follicular fluid.73
The copper IUDs initiate a local sterile inflammatory reaction in the uterine cavity that is toxic for spermatozoa and the oocyte74–76 and act primarily by preventing fertilization.74,77 An in vivo human study that examined several types of IUDs concluded that they most likely act before the oocyte reaches the uterus.78 No direct evidence indicates that any of the currently approved hormonal EC regimens prevent fertilization.51 LNG-EC is ineffective when given after ovulation, it does not affect postovulation events, such as fertilization or implantation,79–81 and does not prevent a pregnancy after fertilization has occurred.82,83 In mice, UPA did not decrease the percentage of fertilized eggs in vitro and did not slow the cleavage speed of embryos in culture.84 The incubation of human spermatozoa with UPA did not affect their ability to bind human tubal tissue explants or to penetrate mouse cumulus–oocyte complexes or zona-free hamster eggs.85
Preventing implantation of the fertilized egg appears to be a very unlikely mechanism.50 There is no evidence that either LNG or UPA act after fertilization has occurred.52 Studies in mice found that subcutaneous LNG, when administered within 3 days after coitus, can prevent the uterine implantation of the embryos,86 but these effects were not shown in humans.51 In an in vitro three-dimensional endometrial construct, LNG did not affect the expression of endometrial receptivity markers,87 and this was confirmed in a randomized single-blinded trial where it was administered orally or vaginally on the day of the LH surge.88 In another in vitro endometrial three-dimensional cell culture system that mimicked the human endometrium, LNG did not inhibit the attachment of human blastocysts.89 An analysis of the endometrial transcriptome in volunteers receiving LNG EC for 1 menstrual cycle found that the treatment did not alter the expression profile of genes associated with endometrial receptivity.90 In women who became pregnant after failure of the LNG EC, no adverse effects such as an increased risk of miscarriage, teratogenesis, or pregnancy complications were observed.91,92 In a review of studies that examined LNG EC, 9 of 10 studies did not find any effects on implantation compared with controls.93 A study that used embryos that would have been otherwise discarded after in vitro fertilization showed, for the first time, that UPA doses used for EC did not affect their attachment to in vitro endometrial constructs, and gene expression levels for 9 well-established endometrial receptivity markers did not change after exposure to UPA.94 A postmarketing study of UPA use in >1 million women reported that the number of miscarriages and ectopic pregnancies was not increased compared with those in the general population.95
PERCEPTIONS ABOUT EC IN THE GENERAL POPULATION
The general level of knowledge about EC is often inaccurate in the US and internationally.9,96,97 A questionnaire administered in 2002 to women in France who were seeking abortions revealed that even though knowledge about EC has improved over the years, and 89% of the participants heard about EC, only ∼38% were aware of the pregnancy risk at the time when they became pregnant, and 48% of those who believed they could get pregnant at the time, later reevaluated and minimized this risk. At the same time, about 2% of the women who believed they were not at risk reconsidered this and used EC nevertheless.98 A 2007 survey of adolescents in New York City schools revealed that fewer than half of the responders had heard of EC.99 In a 2007 survey of female college students from a mid-Atlantic university, 95% of the respondents knew about the availability of EC in the US, but almost 40% were uncertain whether this was the same as mifepristone, which is used for early abortions, and 60% did not believe that they could obtain it if needed.100 A 2012 survey of 7170 fertile women from France, Germany, Italy, Spain, and the United Kingdom found that ∼33% did not know how EC worked, 31% believed that it “has an abortive effect or is like an abortion,” and 10% worried that it could lead to infertility.101 In a 2016 social media survey >60% of the participants described the mechanisms of action of emergency contraceptive pills as preventing implantation of a fertilized egg and 9% described them at postimplantation levels, which would be considered abortion. This highlighted the widespread misunderstanding that exists still about their mechanisms of action.102 An online, confidential survey of 14–21 year old females observed at a US Pediatric and Adolescent Gynecology clinic between 2017 and 2018 found that >80% had heard about EC, indicating an increasing awareness over time, but misunderstandings with respect to their adverse effects were frequent, and participants identified the media as their primary source of information.103 A 2017 cross-sectional study of female undergraduate students from 2 institutions in Brazil found that although nearly 53% of them used emergency contraceptives, only ∼12% received guidance on how to use them, and >25% believed that EC caused abortion.104 Similarly, in a survey in Portugal, >23% of the female respondents believed that EC is an abortive method, and >60% obtained their information from media sources.105
PubMed, Society of Family Planning, American College of Obstetricians and Gynecologists, the World Health Organization.
AREAS OF UNCERTAINTY
The role of media and social media
Misinformation about health-related topics is abundant on social media,106–109 and contraception is not an exception.110 A study of >838,000 Twitter messages on contraceptives posted between March 2006, when Twitter was founded, and the end of 2019, found that the number of tweets during this time increased by almost 300-fold. Long-acting contraceptive methods were mentioned more frequently than short-acting ones and were twice as likely to be positive, but most tweets were negative and, over time, tweets with an emotional tone increased in number. The authors emphasized the need to recognize the role of social media in disseminating information about contraception.111 This is critical, considering that social media users post information related to reproductive health, such as the use of EC,112 and request diagnoses of sexually transmitted infections, a trend that was referred to as crowd-diagnosis, often for second opinions after having received a professional diagnosis.113 A study found that among women with LNG-EC failure, the primary sources of information included friends, TV, and the Internet.114
Social networks, including family, friends, and media, were shown to be important for the contraceptive decision-making in African American and Latina women.115 An analysis of information on EC using a Google search in April 2020 found that the information showed low credibility overall and many web sites were too complex for regular consumers.116 Providing information about contraception on social media can improve users' knowledge,117 as shown by the fact that youth exposed to messages about sexual health on social media were more likely to have used contraception or condoms at the last intercourse.118 To limit the spread of misinformation and misperception about EC, it is important, as previously noted, to avoid the term “morning-after pill,” which falsely implies that it can only be used the day after the intercourse, whereas in reality some forms of EC can be used up to 120 hours after unprotected intercourse.119
Politicization of EC
EC has been increasingly politicized ever since its approval, particularly in the US but worldwide as well.50,120 A survey conducted between 2013 and 2014 that enrolled US health care providers recruited from academic medical centers found that their attitudes with respect to EC was associated with the political climate in the county where they practiced, as measured by the 2012 presidential voting pattern. After accounting for knowledge and attitudes about EC, a 1% increase in the Republican votes in a county was associated with a 2.9% decrease in the odds that a provider from that county would prescribe EC.121
Several states introduced legislation intended to restrict the availability of EC, some of them in the form of refusal laws or conscience clause bills that allow health care workers to refuse providing it to patients if it conflicts with their personal beliefs.50 In recent years, this right was extended to pharmacists and included the right to refuse not only dispensing of EC, but also information about it.122,123 Numerous examples were reported in the US where pharmacists refused to fill EC pills based on conscience clause bills.124 Sometimes this happened because they viewed EC as an abortifacient, a concern that seems to be a growing trend,125 albeit 1 that is not supported by science.52,126 This can cause delays of a time-sensitive medication. For instance, in 2019, a pharmacist in Minnesota refused to fill a woman's EC prescription despite being in stock, and a second pharmacy did not have it and was not able to order it in a timely manner, and sent her to a third pharmacy.127 Based on the right to invoke the conscientious clause argument, pharmacists sometimes refused to dispense contraceptive medication or other types of medication that were prescribed for applications distinct from preventing a pregnancy. For example, a 14-year-old girl from St. Louis who was prescribed a high-dose contraceptive regimen to control abnormal uterine bleeding was berated by her pharmacist, who refused to fill the prescription and accused her of attempting to produce an abortion.124 Considerable debates ensued in 2018, when an Arizona pharmacist refused to dispense a prescription for a woman undergoing a miscarriage,128 and also when a pharmacist in Idaho refused to dispense a nonabortifacient medication that was prescribed to prevent bleeding, suspecting that the woman might have had an abortion.120
With respect to the conscience objection claim, it is critical to note the inequitable burden that it exerts on individuals, preponderantly on those who are disfavored to begin with. For example, people from lower socioeconomic backgrounds, from rural communities (where some pharmacies may close earlier and finding an alternative open location is time-consuming and costly), less access to health care facilities, transportation barriers, and minorities are particularly affected by conscience clause claims. This is particularly challenging considering the time-sensitive nature of EC.129 Thus, these claims may worsen already existing disparities and inequities in society, at a time when there is a desperate need to develop and implement strategies to narrow disparity gaps. The choice of refusing to dispense EC by conscience objectors, despite the inequities that it perpetuates and amidst the lack of choices that a patient is faced with, is referred to as an extreme point of privilege.129
MULTIPLE TYPES OF BARRIERS TO EC
Several types of barriers that limit access to EC have been described. The out-of-pocket cost of LNG EC, with an average between $41–48, is an impediment for many women,44 and a study that investigated the availability of UPA across pharmacies found that the out-of-pocket cost at those able to fill the prescription was a median of $50.130 The association between higher income and higher rates of EC use was presented as evidence that cost may be an important obstacle.28
Keeping EC in a locked cabinet or behind the counter131 is another difficulty. Although the one-pill regimen brand product was available over the counter in 2013, the age restriction label was in place for the generic ones until 2014. The two-dose regimen thus maintained a dual status, without prescription for age 17 and over, and with prescription under age 17. Since April 2016, only the one-dose regimen has been available as an over-the-counter product that does not require identification.32 A 2018 study in southwestern PA found that 26% of the pharmacies kept LNG behind the counter.31 A study conducted in late 2018-early 2019 at pharmacies in Hidalgo County, Texas, found that even though LNG EC was approved as an over-the-counter medication without age restrictions, it was behind security barriers more often than other reproductive health products, including some that had higher mean prices, a practice that has the potential to increase discomfort and delay care.132 In Italy, where over-the-counter EC was approved in 2015 and uptake rates are among the lowest in Europe, interviews revealed that keeping the medication behind the counter created an impediment because of the embarrassment and fear of being labeled irresponsible that some consumers perceived when they had to request it.133 The prescription requirement for UPA, which is more effective than LNG, and the need for a trained clinician to place the copper IUD134 additionally limit access.
Provider knowledge gaps emerge as an additional stumbling block. A survey of health care providers, including physicians, nurse practitioners, and physician assistants, on a broad range of contraceptive topics, found considerable misinformation, particularly among older providers and those practicing family medicine. Of those surveyed, 29% were not familiar with the WHO recommendation to offer EC for up to 120 hours after intercourse. The authors recommended a greater focus on contraception-related topics in family medicine education program, considering that often this setting is where a woman would receive information about contraception.135 A web-based survey of 1684 providers from several specialties who were treating women of reproductive age, conducted between 2013 and 2014, found that only ∼29% of the respondents have heard of UPA and only 7% provided it. Among reproductive health specialists, these percentages were 52% and 14%, respectively.136
An important factor that determines a person's ability to use EC is whether a pharmacy has it available or can order it in a timely manner. An observational population-based study that used a telephone-based secret shopper methodology reported that between the end of 2013 and mid-2014, only 2.6% of 198 retail-based pharmacies in Hawaii had UPA available and ∼23% were able to order it.137 A similar study conducted in 2016 at 533 retail pharmacies from 10 large US cities, with over 500,000 inhabitants, found that <10% of the pharmacies were immediately able to fill a UPA prescription, and 72% of those who did not have it immediately available were willing to order it, but the median predicted wait time was 24 hours.130 Similarly, a study from mid-2018 in southwestern PA found that UPA was immediately available in only 5% of the 407 pharmacies that were contacted and, even though this was not a question in the script, 45% of the pharmacists stated that they never heard of UPA.31
When female callers posing as 17-year-old adolescents called 979 pharmacies in 5 US cities in 2015, after the age restriction had been removed, even though most pharmacies had EC in stock, correct information about their over-the-counter availability was provided only ∼52% of the time. About 8.3% of the pharmacies indicated that it was not possible to obtain it, and this occurred more frequently in low-income neighborhoods.138 A similar study conducted in 2016, in which trained male and female callers posed as 16-year-old adolescents, found that of 1475 randomly selected pharmacies in Arizona, California, New Mexico, and Utah, nearly 94% of national chain pharmacies (but only ∼67% of individually owned pharmacies) stated that the caller could come on their own and does not need a prescription, parental approval, or a photo ID. The authors pointed out that these actions, by hindering access, could negatively affect unwanted pregnancy rates among teens in these states.139 In a similar study conducted during 2015–2016 that surveyed 993 pharmacies, misinformation was provided in ∼10% of the calls made by callers posing as male or female adolescents, but in only 1.6% of the calls made by a physician calling on behalf of a patient of the same age.140
Racial and ethnic disparities
Women of color face significant impediments to obtaining health services for several reasons, such as lack of health insurance coverage,141 discrimination,142,143 and distrust in medical professionals.144,145 These factors make it more difficult for them to get access to reproductive health resources. Even after controlling for socioeconomic factors such as education, income, or access to health care, racial and ethnic disparities have been reported for unintended pregnancies,146,147 cervical cancer, sexually transmitted infection screening,148,149 mental health care,150 and obstetric and perinatal care,151,152 and for women's ability to obtain accurate information related to general health and reproductive health on the internet.153 A Veteran Affairs Health System's study of veteran women found that racial and ethnic disparities also extend to knowledge about contraceptives.154
Disparities in women's access to reproductive health and reproductive health outcomes are shaped by individual-level risk factors and broader social determinants of health such as institutional deprivation.155–157 A meta-analysis and systematic analysis found that among African American mothers, neighborhood segregation was associated with adverse birth outcomes.158
The term contraception desert describes the barriers to purchasing contraception African American women face, even though they are geographically closer to independent pharmacies than Caucasian women. The reasons for these barriers include fewer hours that the pharmacies are open, fewer female pharmacists, a scarcity of patient education brochures on contraception, and more restricted self-checkout options. The only favorable factor that was documented in this context, for African American women purchasing contraceptives, was the presence of an African American pharmacist.159,160 A study that used geographic information systems and spatial analysis in 14 states found that between 17% and 53% of the population for various states lived in a contraceptive desert, and the likelihood was higher for low-income people and minorities.161
Several studies have documented racial and ethnic disparities in contraceptive use,146,147,162 and methods may vary over a woman's life.163 For example, in several studies, African-American women were more likely to use condoms, injectable contraceptives, and long-acting methods163,164 and had higher rates of tubal ligation, which is usually performed in older women or those who already have children. By contrast, Caucasian women were more likely to use oral contraceptives.163–167 Knowledge and attitudes among male partners of color emerged as an additional factor contributing to ethnic and racial differences in contraceptive use.168 In 1 study, Black and Hispanic men were less likely to be familiar with most methods of contraception than their white counterparts.
Natural disasters also disproportionately affect racial and ethnic minorities. In the wake of Hurricane Ike, which made landfall in Texas in 2008, African American female hurricane evacuees reported more difficulties accessing birth control between 2008 and 2010, even though family planning clinics were open.169 In an interview conducted with a small group of African American women evacuated as a result of Hurricane Katrina 5 to 6 months after the hurricane, most did not have access to family planning services, even though they had access before the hurricane.170
The availability of EC to people who have been raped in emergency rooms of Catholic hospitals is a topic of major concern, and particularly consequential considering that the rape-related pregnancy rate in the US among women of reproductive age is 5%.171,172 Structured phone interviews conducted in 2000 with personnel in large US urban hospitals revealed that 12 of 28 Catholic hospitals had policies that prohibited discussing EC with people who have been raped, and although 8 of them mentioned that some information would likely be provided to them, in 4 hospitals, a patient would only find out about their availability by asking. At 7 hospitals, physicians were prohibited from prescribing EC, and 17 of the hospitals stated that their pharmacies were prohibited from dispensing it. The authors pointed out that the conscience clause seems to be resolved in favor of the provider instead of the patient, who expects the health care provider to act in their best interest, and that this would undermine the implicit trust of the doctor patient relationship.173 A 2016 study of hospitals in Washington State that provided reproductive health care found that EC was mentioned in the policies of only 21% of the non-Catholic hospitals, and only in sexual assault in 16% of them, whereas 54% of the Catholic hospitals mentioned it, and always in context of sexual assault. Previously, in 2014, a mandate from the Governor required all hospitals to publicly post their reproductive health policies. Regardless of their affiliation, hospitals' reproductive health policies overall provided more confusion than clarity about contraceptive services.174
Misinformation is an additional stumbling block that hinders or delays the use of EC. An example is the concern that EC could affect future fertility,175 or the unfounded belief that its availability could encourage risky and irresponsible behaviors among teens or increase the frequency of sexually transmitted infections, neither of which is supported by the scientific literature.131,176,177
Amidst the politicization and misinformation that abound, improving health literacy becomes a critical and urgent task in context of reproductive health,178–181 particularly if we consider that at least 90 million Americans are estimated not to understand basic health information.182,183 Two more recent and intimately interconnected concepts, media health literacy184 and eHealth Literacy185 enable individuals to better recognize, analyze, respond to, and communicate health-related content communicated through the media, including content from electronic sources, and are particularly consequential considering the vast amount of health-related information that is pervasive online and on social media platforms.186
Comprehensive sex education was shown to have a positive effect on contraceptive use.187–189 Although sex education in schools has itself been a topic of considerable debate,190,191 comprehensive sex education was shown to reduce teen births and to lower the risk of sexually transmitted infections.187,190,192 As of mid-2022, only 29 states and the District of Columbia require sex education in public schools, and only 18 states required the information to be medically accurate when it is provided.121,193,194
The US has one of the highest teen pregnancy rates among affluent countries.195 About 49% of the pregnancies in the US are unintended, and many of them will end in abortion.115 Narrowing the widespread and pervasive gaps in access to EC could decrease the likelihood of unintended pregnancies. A study conducted in Utah between 2000 and 2006 found a statistically significant correlation between the increased number of LNG EC prescriptions and decreasing abortion rates.26 The Contraceptive CHOICE Project, one of the largest prospective cohorts in the US, found when reversible contraception was made available for free for 2–3 years, a 4.6-fold decrease in pregnancy rates, a 4.8-fold decrease in birth rates, and 4-fold decrease in abortion rates among teens from the project compared with the national rates,.196 Other studies did not find a similar link, but it is currently recognized that even if there may not be an impact on the rate of abortions at the population level, access to EC lowers abortion rates at the individual level.197 As part of reducing barriers to access, it is critical to safeguard the protection of special populations, including adolescents,57,198 non-English speaking patients,198 individuals at hospitals with religious affiliation,199,200 sexual assault survivors,201 women facing disaster situations,202 patients from rural areas,203 and military and veteran populations.131,204
A notable difference between the copper and hormonal IUDs is the effect on menstruation. The LNG IUD leads to shorter and lighter periods, whereas the copper IUD can cause heavier and crampier menses.205 Having an IUD with a different side-effect profile for continued use after placement for EC could lead to increased uptake. A randomized clinical trial conducted at 6 clinics in Utah included 711 women who sought EC after at least 1 instance of unprotected intercourse, and found that the LNG 52-mg IUD was noninferior to the copper IUD when used as an EC method in the first 5 days after unprotected intercourse.17 The possibility to further explore and develop official LNG- IUD for EC protocols is of considerable interest, particularly because unlike the currently approved oral LNG EC regimen, the LNG-based IUD is not affected by the woman's body weight and provides a promising alternative for overweight and obese patient populations.42,43
It is also important to consider recent studies that showed that the copper IUD and LNG IUD can be placed up to 14 days after un- or under-protected intercourse for EC. This extends the window for patients and providers to prevent unplanned pregnancy.206,207
Abortion and contraception are essential components of reproductive health care. With the restrictions to abortion that were recently implemented in some states in the US, and are expected in others, the demand for EC is anticipated to increase. LNG and UPA, the 2 oral hormonal EC pills currently used in the US, are safe and effective and have almost no medical contraindications. An in-depth understanding of the mechanisms of action points toward the fact that hormonal EC delays or prevents ovulation and it is not an abortifacient. Barriers to EC were described which present significant challenges for certain vulnerable populations and minority groups. These obstacles threaten to worsen existing disparities. Initiatives that provide convenient, accessible, and affordable EC are an important part of efforts to narrow the disparity gap in society and to improve public health.
The authors acknowledge that not all people who have a uterus identify as female and those who identify as transgender, gender nonbinary, and those on the gender spectrum can experience pregnancy and may seek contraception. The authors use the term woman for brevity's sake throughout the document and request the reader's patience and understanding.
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