What some women want? On-demand oral contraception

Publication date: 2014

Review a What some women want? On-dem Elizabeth G. Raymonda,⁎, Tara Shocheta, Jen aGynuity Health Projects, bPATH, Seattle cInternational Consortium for Emergency Contraception, hos 10 A n-de or 10 tablets of levonorgestrel 0.75 mg was commercially the act— rather than daily. Ten clinical trials of the regimen Contraception 90 (2014) 1 marketed in several countries in Eastern Europe and Asia. that together included more than 2600 women who used the pills over a period of 1–16 months found a combined pregnancy rate of 5.1 pregnancies per 100 woman–years, approximately comparable to the rates observed among typical users of other coitus-dependent contraceptives such as condoms and diaphragms [1]. No serious adverse effects occurred in the trials, although bleeding irregularities, nausea, and other symptoms associated with progestin-based contra- ceptives were not uncommon. Despite the side effects, ☆ Funding: This work was supported by a grant from the Bill & Melinda Gates Foundation. ☆☆ Contributions: EGR conceived of the paper and drafted the initial manuscript, and all authors participated in literature searching, interpretation and manuscript revision. ★ Conflicts of interest: None of the authors has any conflict of interest. ⁎ Corresponding author. Gynuity Health Projects, 15 East 26th Street, attitudes regarding a coitus-dependent oral contraceptive; all suggested substantial interest in using it. Nine studies assessed actual use of oral tablets on demand for primary contraception. In these studies, 9–97% of women in the analysis populations reported using the pills on demand as main method, although frequency and consistency of use varied. Reported reasons for interest in or use of this contraceptive approach included convenience, ease of remembering, ability to conceal use, lack of coital interruption, and infrequent sexual activity. Three studies were clinical trials of investigational on-demand oral contraceptives which reported Pearl indices ranging from 6.8 to 53 pregnancies per 100 woman–years. Conclusion: Data from a variety of settings suggest that demand for an on-demand oral contraceptive may be widespread. The effectiveness of this potential method is not established, however. Considering the seriousness of the unmet need for contraception, further development research into the public health benefits and risks of such a method would be worthwhile. Implications: Demand for an on-demand oral contraceptive may be widespread. Efforts should be made to further explore the possibility of developing such a method. © 2014 Elsevier Inc. All rights reserved. Keywords: Pericoital; Emergency; Repeat; Survey; Coitus dependent 1. Introduction Decades ago, an oral contraceptive product containing 4 This product differed from current oral contraceptives in that women were instructed to take the pills only “on demand”— that is, only when they had sex, shortly before and/or after Study design: We used Medline and collegial contacts to find published and unpublished studies conducted or reported in the past 15 years with information assessing women's interest in using any oral drug preparation, including emergency contraceptive pills, in a coitus- dependent manner either repeatedly or as a primary or planned pregnancy prevention method. Results:We found 19 studies with relevant information. The studies were conducted in 16 countries. Eight studies provided data on women's Received 2 February 2014; revised Abstract Objective: To summarize evidence regarding current demand for o Suite 801, New York, NY 10010, USA. Tel.: +1-212-448-1230; fax: +1- 212-448-1260. E-mail address: eraymond@gynuity.org (E.G. Raymond). http://dx.doi.org/10.1016/j.contraception.2014.04.008 0010-7824/© 2014 Elsevier Inc. All rights reserved. rticle and oral contraception ☆,☆☆,★ nifer Kidwell Drakeb, Elizabeth Westleyc New York, NY, USA WA, USA ted by Family Care International, New York, NY, USA pril 2014; accepted 15 April 2014 mand oral contraception. 05–110 participants in the trials generally liked the method and used it continuously for more than 6 months on average. The product reportedly sold quite well for at least 10 years [2]. needing to advise women about frequent use of ECPs. In this by consulting with experts working on issues related to 106 E.G. Raymond et al. / Contraception 90 (2014) 105–110 emergency contraception. We used our judgment to deter- mine whether each report included pertinent information. 3. Results We found 19 studies that met the above criteria. All of these were either previously known to us through our work on emergency contraception over many years or were identified through contacts with colleagues. Despite our best creative efforts, our Medline search strategies did not find additional information about this method, which is yet nonexistent and has no standard name. The studies were conducted in a total of 16 countries. We grouped the 19 studies into three categories. 3.1. Studies that assessed women's attitudes about an on-demand oral contraceptive Eight of the studies provided direct data on women's attitudes about routine coitus-dependent oral contraceptive paper, we summarize evidence regarding current demand for on-demand (also called “pericoital”) oral contraception. 2. Materials and methods We aimed to find published and unpublished studies conducted or reported in the past 15 years (since 1998) with information assessing women's interest in using any oral drug preparation, including ECPs, in a coitus-dependent manner either repeatedly or as a primary or planned pregnancy prevention method. To locate these reports, we performed multiple PubMed searches including the follow- ing terms either alone or in various combinations: on- demand, pericoital, postcoital, visiting pill, repeat, contra- ception, oral, emergency contraception, levonorgestrel and mifepristone. We supplemented these searches by reviewing reference lists of the papers identified in primary searches and Nevertheless, marketing of this product was discontinued during the 1990s, in part because of concerns about overuse [2] and also because of the conviction that women should use more effective methods with fewer side effects [3]. The manufacturer introduced a new product that contained only two tablets per package and that was explicitly indicated for emergency treatment after unplanned contraceptive mishaps or failure to use contraception during sex. Levonorgestrel- based emergency contraceptive pills (ECPs) are now widely available worldwide. However, recent studies suggest that the original concept of on-demand oral contraception as an ongoing family planning approach continues to have appeal, at least to some women in some settings. This information is of interest to researchers working on the development of new contraceptive methods and may also be relevant to clinicians and program managers use (Table 1). In three of these studies, researchers described a hypothetical on-demand oral contraceptive pill to conve- nience samples of subjects drawn from clinics, schools and the community, and they ascertained subjects' thoughts about it. Two of the studies were surveys conducted in the United States [4] and Kenya and Nigeria [5], and the third was a set of focus groups and in-depth interviews with women and men in Uganda and India [6]. The descriptions of the imaginary pill included basic instructions for on-demand use. The United States and Uganda/India studies provided further detail: that the pill would be intermediate in efficacy between condoms and daily oral contraceptive pills, that it probably would cause irregular bleeding and that it would not protect against sexually transmitted infections. All 3 studies found favorable reactions to the on-demand pill. In the United States, Kenya and Nigeria, 58%, 48% and 40% of women, respectively, said that they were interested in using it [4,7]. In Kenya and Nigeria, 39% and 37%, respectively, indicated that they were likely to adopt the pill as their primary contraceptive method, and among women who had ever previously used ECPs, these figures were even higher: 66% and 79%, respectively. Interest was associated with various subject characteristics: Black race, difficulty obtaining prescription contraceptives, recent unprotected sex, recent abortion in the United States, and higher education, prior ECP use and prior use of other short- acting family planning methods in Kenya and Nigeria. In each of these African countries, more than 20% of women who had never used modern contraceptives said that they would be likely to adopt the imaginary pill as a main method (D. Chin-Quee, personal communication). The study in Uganda and India did not provide quantitative results but reported that women were generally enthusiastic, especially younger unmarried women [6]. Across all three studies, perceived advantages of the hypothetical method included ease of remembering, appli- cability for women who have infrequent sex, requirement to use only when needed, potential for use before or after sex and female control. Women in Uganda also highlighted the possibility of taking the pill without their partners' knowledge. In the United States, India and Uganda, some respondents cited superior efficacy to condoms. Some women in each study noted concerns about the method, including insufficient efficacy, fear of forgetting and side effects. Mechanism of action was not specifically cited as an issue by women in any of the studies. A fourth study asked abortion clients at six clinics in the United States about the importance of 18 features of contraceptives, such as effectiveness, side effects, ease of use, control and effect on enjoyment of sex [8]. The authors concluded that an on-demand oral pill would have at least 64% of the features considered by the women to be extremely important. This method would thus have more highly desirable features than almost any other currently available method, including daily oral contraceptives (60%), intrauterine devices (56%), injectables and implants (51%) or condoms (42%). If it could be obtained over the counter, the on-demand pill was judged to be a perfect or good match for 27% of women, more than any available method except the vaginal ring. Four additional studies questioned women about their knowledge and attitudes regarding currently available used routinely after every sexual intercourse as long as the woman does not want to be pregnant [10]. A qualitative, study interviewed 30 prior ECP users in the United States. Respondents who reported infrequent intercourse felt that ECPs were a preferred method of contraception. For these women, a postcoital contraceptive may be a “first-line Table 1 Studies with information on women's interest in using an on-demand oral contraceptive Lead author Location, year of data collection Population n Study design Foster [4] 9 states, United States, 2011 Women in abortion and family planning clinics 1616 Self-administered questionnaire Chin-Quee [5] Nairobi, Kenya and Lagos, Nigeria, 2011 Women in busy shopping areas 6165 Interviewer-administered questionnaire Cover [6] Kampala, Uganda and Lucknow, India, 2012 Women and men sampled through communities and clinics. 241 women, 40 men Focus groups and in-depth interviews Lessard [8] 6 states, United States, 2010 Female clients at six large abortion clinics 574 Self-administered questionnaire Arowojolu [9] Lagos, Ogun and Oyo states, Nigeria, 1997 Female students at 7 post-secondary schools 1072 Self-administered questionnaire Ezebialu [10] Nigeria, 2009 Survey of female university students 675 Interviewer-administered questionnaire Neustadt [11] Chicago, United States, 2006 EC users recruited by advertisements 30 In-depth interviews Teixeira [12] Senegal, Burkina-Faso and Ghana, 2005–2007 Personal acquaintances of interviewers 149 women, 77 men In-depth interviews tracep 107E.G. Raymond et al. / Contraception 90 (2014) 105–110 contraceptives. Two were surveys of Nigerian university students. One found that 37% would like to or planned to use ECPs in the future (presumably not only for emergencies) because they perceived ECPs as more convenient, safer and/ or more effective than regular methods [9]. In the other, 59% of respondents felt that emergency contraception should be Table 2 Studies with information on use of post-coital oral hormones as primary con Lead author Location, year of data collection Population Lerkiatbundit [13] Hadyai, Thailand, 1999 Women in shopping malls or purchasing EC who had previously used EC at least once Addo [14] Kumasi, Ghana, 2005 Sexually active female university students Keesbury [15] 5 towns in Kenya, 2007 Women purchasing ECPs in pharmacies L’Engle [16] Accra, Ghana, 2008 Women purchasing ECPs in pharmacies Chin-Quee [17] Accra Ghana, 2008 Women purchasing ECPs in pharmacies Chin-Quee [5] Lagos, Nigeria and Nairobi, Kenya, 2011 Women in shopping areas Morgan [18] 5–6 cities in Nigeria and Kenya, 2010–2011 Sexually experienced women in representative households Gold [19] Ethiopia, 2011 Young women purchasing ECPs in pharmacies contraceptive strategy” rather than a backup method [11]. Finally, a qualitative study in three countries in West Africa found that routine planned postcoital contraception is a familiar concept and is commonly practiced using traditional substances or ECPs [12]. Along with the previously mentioned advantages, respondents in that study expressed tive n Use of tablets as primary on-demand contraception 100 97% used ECPs as a prospective planned contraceptive 225 8.8% used ECPs as main contraceptive method 147 48% used ECPs every time or most times they had sex in past 6 months 24 “Almost all” considered ECPs to be main contraceptive method 232 35% were using ECPs as main contraceptive method Women who had ever used ECPs: 526 in Nigeria, 547 in Kenya, 41% in Nigeria and 15% in Kenya considered ECPs to be main contraceptive method Weighted 12,487 Nigeria, 7785 Kenya; women who had used EC in past year 300 Nigeria, 420 Kenya Of those who used ECPs in past year, 38% in Nigeria and 12% in Kenya considered it to be their main method. 46 “Many” used ECPs repeatedly, including at every sex act or as main contraceptive method 108 E.G. Raymond et al. / Contraception 90 (2014) 105–110 a fear of using hormones continuously over a long time period and felt that intermittent use of contraceptives represented freedom and autonomy. 3.2. Studies that quantified actual on-demand use of oral tablets for primary contraception We identified eight studies, including one of those mentioned above [5], that included quantitative data on women's reported use of marketed hormonal tablets either as a primary contraceptive or at most or all coital acts (Table 2). One was conducted in Thailand [13], and 7 were conducted in Africa [5,14–19]. The sample sizes ranged from 24 to more than 1000 women. Only one of the studies used a population-based sampling frame [18]; of the others, one intercepted a convenience sample of women in shopping areas [5], one surveyed university students [14] and the rest surveyed women who were purchasing ECPs. The Thai study was performed only 2 years after the previously mentioned commercially marketed on-demand oral contra- ceptive product had been taken off the market. In six of the studies, the hormone tablets used were ECPs, but in two studies, both conducted in Ghana, some women reported using other drugs, particularly norethindrone tablets that were officially labeled for treatment of irregular menses and other gynecologic disorders but not for contraception [14,16]. In the eight studies, the reported proportion of the analysis population who were using the hormone tablets on demand as a primary contraceptive ranged from 9% to 97%. The lowest figure came from a study that included women who had never used ECPs; [14] the other studies that all excluded such women from the analysis population not surprisingly reported higher prevalence of the practice. As we explained in an earlier publication [20], studies that enroll women who are actively purchasing ECPs should be expected to oversample frequent users and thus will tend to overestimate the use of ECPs as a primary method. However, the two most recent studies, which were also the largest, were deliberately designed to prevent this bias by recruiting women in venues other than ECP outlets. Both found that in Nigeria, quite high proportions of prior ECP users — 41% in one study [7] and 38% in the other [18] — were using the pills as their main contraceptive method. The frequency and consistency with which the admitted on-demand oral contraceptive users actually took the tablets varied among studies. In the Thai study, in which almost all subjects were using ECPs as a primary method, 39% took them more than once a week [13]. In one study in Kenya, 48% of the total population purchasing ECPs claimed to use these pills most or all the times they had sex, and even more — 58% — had used them at least once previously in that same month [15]. In contrast, in a study in Nigeria, although more than 66% of recent ECP users had sex at least once a week and 41% considered ECPs to be their main method, at least half the population used the tablets four or fewer times in the prior 6 months. Similarly, a study in Ghana found that many women using ECPs as a main method used them very inconsistently: among those who reported sex twice a week or more, 77% purchased ECPs at most six times in the prior year [17]. None of the reports provide data on characteristics of the subgroup of women who claimed to be using the ECPs or hormone tablets in an on-demand fashion. In Thailand, where nearly the entire study population was in that subgroup, the women were demographically diverse: ages spanned from younger than 20 years to older than 35 years, 59% had education beyond high school and 53% were neither married nor cohabiting [13]. Several of the studies reported the reasons that women chose to use the pills in an on-demand manner as their primary contraceptive. These included convenience, ease of remembering, ability to conceal use from male partner, lack of coital interruption and infrequent sexual activi- ty [13,15,16]. In some studies, women reported side effects such as menstrual cycle disturbances, nausea and dizziness and were aware of contraceptive failures, but they apparently did not find these problems excessively troublesome [13,16]. In one study, most subjects had no experience with other contraceptive methods and were manifestly ignorant about their benefits and risks; they also overestimated the efficacy of ECPs compared to other methods [16]. In comparison, in the Thai study, most women had used at least one other modern method [13]. One study reported use of the on- demand pills in conjunction with other methods, including condoms, periodic abstinence, withdrawal and traditional herbs [17]. A ninth study, conducted in family planning clinics in Utah in the United States, found that 7% of 1038 women purchasing ECPs reported having used the pills six or more times in the prior year [21]. The authors speculated that some of these “extensive users” may have been using ECPs as “more than Plan B” (i.e., not just for emergencies). However, the study did not investigate use of the pills as an explicit main contraceptive method. The extensive users were not statistically different demographically from occasional users, but they were more likely to have had multiple sexual partners currently and in the past and also to have used alcohol or illicit drugs at their last sex act. They were also more likely than other women to overestimate ECP efficacy. 3.3. Clinical trials of efficacy and safety of an on-demand oral contraceptive Three clinical trials met criteria for this review. Two were designed to assess the efficacy and safety of an investiga- tional product consisting of 0.75-mg tablets of levonorgestrel taken around the time of each sex act. The first study, conducted by the World Health Organization in the 1990s, enrolled 295 women at six sites in China, Pakistan, Slovenia, Cuba and Russia. Over all sites combined, the Pearl index was 6.8 pregnancies per 100 woman–years [95% confidence Women's cited reasons for interest in this approach to 109E.G. Raymond et al. / Contraception 90 (2014) 105–110 family planning were consistent across the disparate study settings. For some women, particularly those who have infrequent sex, an on-demand pill seemed intuitive: since they incur the risk of pregnancy only intermittently, they should not need to take pills every day. The link between pill ingestion and the sex act was felt to aid in compliance, a notorious problem with daily pills [24]. Women also appreciated the ability to use the method after sex and without the cooperation or even the knowledge of their partners. Concealing contraceptive use from men is one strategy recommended for women in relationships affected by violent or nonviolent forms of reproductive coercion [25]. Although these data are intriguing, we advise caution in using them to anticipate the potential public health impact of an on-demand oral contraceptive. Many of the 19 studies surveyed women who had previously used ECPs or were about to do so; in most of the world, such women are a small minority of the general population. The women in these studies may have had greater interest in the on-demand method than the general public, who may be better informed interval (CI)=3.1–12.9] [3]. The second trial was conducted in 2010–2011 in the United States and Brazil [22]. Only 72 of the planned 300 subjects were enrolled before the trial was terminated in part because of slow recruitment. Whether the problem was aversion to the method itself or some other factor related to the trial was undetermined. The primary analysis showed a Pearl index of 22.4 pregnancies per 100 woman–years (95% CI=4.6–65.4). No serious adverse events occurred in either study. In the earlier study, 66% of participants expressed favorable opinions of the method. In the later study, 81% stated that they would be interested in using the method in the future if it were found to be effective. The third trial included 23 women who were asked to take mifepristone 10 mg as soon as possible after each intercourse act but no more often than every 5 days. In 68 months of follow-up, the Pearl index was 53 pregnancies per 100 woman–years. Women had difficulty implementing the 5-day limit, and 2 of the 3 pregnancies occurred in women who were noncompliant with the instructions [23]. 4. Discussion Data from 19 studies conducted in 16 countries suggest that demand for an on-demand oral contraceptive may be widespread. Across these studies, not only did substantial proportions of women like or support the concept in theory, but some were actually using it, having created the method for themselves with available products. In two large surveys [5,18], a sizeable proportion of women (at least 38% in Nigeria and 12% in Kenya) who had recently or ever taken ECPs considered the pills to be their primary contraceptive method. This behavior seems particularly noteworthy since currently in those countries and throughout the world, ECPs are promoted and explicitly labeled for emergency use only. about other contraceptive options. These data obviously thus are not generalizable to the full spectrum of women in need of contraception. In addition, most studies were conducted in developing country settings where knowledge and availabil- ity of standard contraceptives may be relatively limited and where misunderstandings about both ECPs and other contraceptives abound. Indeed, a 28-month demonstration project in Lothian, Scotland apparently found essentially no routine use of ECPs among nearly 18,000 women who received five free packages of the drug [26]. Clinical trials conducted in the United States in which women had free and easy access to ECPs also found low incidence of repeated use [27,28]. Furthermore, the studies reviewed here do not address potential problems that might arise among women who did adopt on-demand oral contraceptives. Substitution for other contraceptives might limit the benefit of the new method in reducing unintended pregnancy rates, and if the on-demand pills replaced condoms, risk of sexually transmitted infections might increase. Some reassurance on this point was provided by the findings of one study conducted in Nigeria and Kenya suggesting that a substantial proportion of women who had never used contraception would consider using a hypothetical on-demand oral contraceptive, whereas interest was relatively low among users of highly effective contraceptives [5]. However, data from actual use trials would be valuable. Another concern is the difficulty of recognizing pregnancy due to method failure given that bleeding disturbances, including amenorrhea, are an expect- ed side effect of the method. New approaches to manage this and other service delivery issues would need to be developed as part of the introduction of the new method. Finally, the effectiveness of on-demand oral contracep- tion used over a prolonged interval has not been established. In theory, even a moderately efficacious method could be quite effective in actual use if women like and use it more consistently than they would available alternatives. Trials of levonorgestrel conducted many years ago had promising results and convincingly demonstrated the safety of repeated use of levonorgestrel in doses as high as 1 mg [1]. However, the only recent trial of tablets containing levonorgestrel 0.75 mg, although small, found a pregnancy rate higher than most currently recommended contraceptive methods [22]. Until more definitive data are obtained, the routine use of ECPs as a prospective strategy for ongoing contraception is not recommended. Nevertheless, the available evidence of demand for on- demand oral contraception has sparked interest on the part of pharmaceutical companies and nonprofit organizations in developing a marketable product. The process would be challenging. This method would likely not meet typical regulatory expectations regarding the efficacy of systemic hormonal contraceptives. Furthermore, it would undoubted- ly raise objections: in a recent study in Uganda and India, although some health providers and key opinion leaders recognized that the potential method would fill a demonstrated need, others expressed concern that the method would cause excess side effects, encourage promis- cuity and deter use of more effective contraceptives and condoms [29]. 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[28] Raine TR, Harper CC, Rocca CH, et al. Direct access to emergency contraception through pharmacies and effect on unintended pregnancy and STIs: a randomized controlled trial. JAMA 2005;293:54–62. [29] Cover JK, Drake JK, Kyamwanga IT, Turyakira E, Dargan T, Harner- Jay C. Stakeholder and provider views regarding pericoital contracep- tive pills in India and Uganda. Stud Fam Plann 2013;44:431–44. [30] Shelton JD. Repeat emergency contraception: facing our fears. Contraception 2002;66:15–7. populations such as those where many of the 19 studies were conducted, and the hope that this method could fill an What some women want? On-demand oral contraception 1. Introduction 2. Materials and methods 3. Results 3.1. Studies that assessed women's attitudes about an on-demand oral contraceptive 3.2. Studies that quantified actual on-demand use of oral tablets for primary contraception 3.3. Clinical trials of efficacy and safety of an on-demand oral contraceptive 4. Discussion References

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