Carraguard ® Acceptability Among Men and Women in a Couples Study in Thailand

Abstract

Objective:

The aim of this study is to evaluate the use and acceptability of Carraguard^® among men and women enrolled as couples in a microbicide trial.

Materials and Methods:

Focus groups were conducted with participants in a 6-month randomized, placebo-controlled trial that enrolled sexually active, low-risk couples in Thailand. Participants were blinded as to which gel they had received at the time of the discussions.

Results:

Most men and women liked the gel and found it acceptable. The majority of men and women thought that using the gel increased sexual pleasure, although participants disagreed about whether using the gel increased sexual frequency. Drawbacks of gel use included that it was too wet or messy, and nearly all respondents thought that the applicator was too hard. Most men and women questioned the utility of using the gel among married couples since gel use was tied to perception of HIV/STI risk. However, those who perceived themselves to be at risk expressed interest in using the product as an alternative to condoms. Many women were particularly interested in a product that also had contraceptive properties. Gel use also raised issues of trust and fidelity among couples and questions about men's ability to detect women's use of the product.

Conclusion:

Men and women in this study found the gel acceptable and thought that it should be made available if it is found to be safe and effective. Strategies for marketing a potential microbicide product must take the target population into consideration. For married couples, key considerations may be partner dynamics and trust issues, whereas messages focusing on sexual pleasure or disease prevention may resonate more strongly with sex workers or other populations.

Introduction

Globally, 33 million people were living with AIDS in 2007, half of whom were women.¹ As the number of HIV infections continues to rise and the burden of disease increasingly falls on women, more attention is being paid to the potential role of microbicides in preventing disease transmission. Microbicides are topical products designed to prevent HIV and other sexually transmitted infections (STIs). Numerous microbicide candidates are being tested in advanced human clinical trials, and many more are in earlier stages of development.² Microbicides have the potential to significantly impact the number of HIV infections if found to be both effective and acceptable among diverse populations.

Vaginal microbicides offer a unique HIV-prevention strategy since women would initiate use, potentially without male partner involvement. Proponents of microbicides maintain that these features are particularly important for the many women who have difficulty negotiating condom use or mutual monogamy with partners. Although condoms are highly effective at preventing disease transmission, condoms are often perceived as inconvenient and diminishing sexual pleasure.^3–4 Condom use can also be especially sensitive among partners since a request to use condoms can be seen as a sign of infidelity or distrust in the relationship.⁵ Additionally, the desire for children can make the trade-offs between using condoms for disease prevention and becoming pregnant difficult to assess.

Product acceptability has been an integral component in the development of microbicides, since the introduction of any new product will be successful only if it is acceptable to women and men in different cultural contexts.^6

–9 A recent review summarizing the existing research on microbicide acceptability identified 61 studies, the majority of which reported on product characteristics such as volume, lubrication and formulation, and preference for a contraceptive or noncontraceptive product.¹⁰ A few studies addressed the acceptability of applicators,^11–12 whether women should consult their partners before using a microbicide, and the possibility for covert use.^{10,13

–20} Literature on men's opinions about microbicides has shown that men believe that they should be consulted first or that partners should discuss microbicide use jointly.^5,21

–25 The literature on women's opinions about this issue is mixed. While many women believe that women should tell their partners about microbicide use²⁶ and that they would not need to use a product covertly,²⁷ several acknowledged the importance of being able to use the method discretely.^{14–15,26,28}

To date, most published studies report on attitudes toward a hypothetical product rather than experiences with an actual microbicide under development. The few published studies that explored acceptability during actual use have enrolled low-risk women for a short period of time,^{21,26,29
–31} and although most of these participants supported the introduction of microbicides, they may not necessarily have seen themselves as candidates to use them.^26,29 In this paper, we report on the actual use and acceptability of Carraguard^®, a carrageenan-based candidate microbicide developed by the Population Council, among couples participating in focus groups conducted with clinical trial participants in Chiang Rai, Thailand. This study evaluated couples' experiences using the product, a unique approach that allowed us to investigate the couple dynamics of microbicide use. Our study also enrolled low-risk couples but in a high-risk area. At the time of our study, HIV was widespread in Northern Thailand, with prevalence rates peaking among young men at 17.3% in 1992 and 11% among childbearing women in 1994. Although rates of HIV infection subsequently dropped among these groups because of significant government intervention, HIV prevalence rates among female sex workers have been on the rise (44% in 1999).³²

Materials and Methods

We collected qualitative acceptability data as part of a 6-month randomized, placebo-controlled, triple-blind safety and acceptability study of Carraguard^® among low-risk heterosexual couples in Chiang Rai, Thailand. Carraguard is a polyanionic compound derived from the seaweed Chondrus crispus; a recently published phase-3 effectiveness trial did not provide evidence that Carraguard could prevent HIV infection.³³ Carraguard is not a surfactant like previous unsuccessful microbicide candidates (N9, Savvy) but has properties similar to another compound, Pro2000, which is still being tested for effectiveness against HIV acquisition. Carraguard was safe for human use when the trial began and is currently being developed as a vehicle for other potential microbicide compounds. This trial was conducted as part of a collaboration between the Thailand Ministry of Public Health, the U.S. Centers for Disease Control and Prevention Collaboration (TUC), and the Population Council.

The detailed study methods have been reported elsewhere,³⁴ but in brief, 55 low-risk couples were recruited from family planning clinics and through meetings organized by local health workers. “Low-risk” was defined as couples who were married, who had no current STI, and who did not report other partners in the past year. Screening began in June 2001 and study follow-up was completed in June 2002. All participants provided written informed consent and achieved a score of 80% or better on a comprehension test of the study aims and protocol. Safety and acceptability were assessed for a total of 12 months. Participants were asked to apply the product three times per week (roughly every other day, with or without sex). Participants were required to insert the product using a Microlax® applicator one hour before sex and to use a condom every time sex occurred. The applicator comprised a small bulb that participants pressed using the thumb and the forefinger to push approximately 4 ml of gel through an elongated nozzle into the vagina. They were then instructed to record their experiences using the product and condoms in coital diaries and to return the diaries and used applicators to the study clinics. The Institutional Review Board at the U.S. Centers for Disease Control and Prevention Collaboration (TUC), the Institutional Review Board at the Population Council, and the Ethical Review Committee of the Thai Ministry of Public Health approved the protocol for this study.

All 52 couples who completed the trial were invited to participate in focus group discussions. Couples who were willing to be considered for mixed-sex groups participated in couples groups, while men and women who preferred single-sex groups were recruited for those groups. In all, 21 couples and 9 individuals (51/104 individuals) agreed to participate. Couples or individuals were reimbursed 300 baht (∼$6.00) for transportation. Six focus group discussions were conducted with women and men in both study arms: two groups of men (total n = 13 men), two groups of women (total n = 18 women), and two groups of couples (total n = 10 couples). Participants were blinded as to which gel they had received at the time of the discussions. Two Thai female moderators trained in semistructured interview protocols conducted the discussions and were assisted by a clinic staff nurse and a note taker. Moderators used a semistructured interview guide covering questions pertaining to the product's physical characteristics, the effects of product use on the sexual experience, partner dynamics surrounding product use, the impact of product use on risk behavior, and strategies for marketing and promoting a potential microbicide candidate. Discussions, which lasted roughly 1½ to 2¼ hours, were conducted in northern Thai and were tape-recorded. Recordings were then transcribed into Thai by Thai bilingual research staff who lived in the same communities as the study participants; recordings were later translated into English so that transcripts could be imported into Atlas.ti qualitative software (Scientific Software Developments 2003) for analysis. Using the qualitative software, the data were sorted thematically based on a series of codes derived from the semistructured interview guide. Two researchers trained in qualitative analysis read and coded the data independently. As new themes emerged during the coding process, the researchers revised the codebook and recoded the data a second time. All coding decisions were reviewed jointly; any disagreements were resolved during discussions with the larger qualitative study team. A final set of agreed-upon coded text was used for analysis. Because of similarities in the responses in the men's, women's, and couple's discussions, data were analyzed across groups. Where there were differences, we reported findings by group.

Detailed safety data from the clinical trial have been published previously.³⁴ Acceptability data were also collected through structured interviews at day 14 and months 1, 3, and 6 of follow-up. Results from the structured interviews have been published elsewhere.³⁵ In that analysis we found no difference in acceptability by study arm (placebo or Carraguard) and also found similar overall responses to close-ended acceptability questions between men and women.³⁵

Results

Participants' characteristics

A total of 28 women and 23 men participated in the focus group discussions. The average age of the women was 32 years, and the average age of the men was 36 years. Men and women had similar levels of education: 5.5 years for men and 5.7 years for women (primary school education). On average, couples had been married for 12 years, with a range of 1 to 27 years. Among all participants, only 6 couples had been married for fewer than 5 years.

Physical characteristics of the product

Nearly all respondents liked using the gel and said that the gel felt “smooth” and “natural.” Most participants described the gel as odorless, which they considered a positive trait. However, some men responded that they did not like the smell, although the product is odorless. Both men and women found the gel too wet and watery and described the gel as “messy” because it would spill out before, during, and after intercourse; these characteristics were perceived as negative. Many male respondents thought the gel should be thicker, similar to a cream or toothpaste, and some suggested that the gel be made into suppositories. Female participants discussed strategies to prevent excessive spillage, including inserting the gel deeper into the vagina, inserting the gel well before intercourse, or not using all of the gel in the applicator. Many participants suggested cutting the volume in half.

Despite the displeasure with the composition and volume of the gel, most men and women liked the added lubrication that it provided and said that the gel made sex more comfortable. One woman explained, “Usually I would be quite dry, so it hurts; with gel, it's smoother” (couples' group). A man added that the gel “helped when [he] was in the mood and she wasn't” (couples' group). Some men and women thought the gel would be particularly useful for older couples who might have difficulty with natural lubrication.

One male participant pointed out that preferences for particular physical qualities of the gel might be different depending on whether it was being used for disease protection or for sexual pleasure. He indicated that if the gel was effective at preventing HIV, people might be more forgiving of some of the nuisances: “If we're talking about pleasure, [the quantity] is way too much. If we're to use it for protection, not for sexual pleasure, then this quantity is all right” (men's group).

Nearly all respondents thought that the applicator could be improved. Most men and women felt that the applicator was too hard, making it difficult to squeeze the gel out. A few male respondents also said that the neck of the tube was too small and pointy. A softer tube, one that could be squeezed using only one hand, was suggested. A few women also recommended making the tube transparent in order to see how much gel had been used. Overall, the majority of men and women wanted the applicator to be convenient and discreet.

Effects on sexual experience

Most participants thought that the lubrication provided by the product improved the sexual experience and made sex more pleasurable. One man explained that “subconsciously the feeling increased because of the gel” (couples' group), while another said that “it helped a little, brought up the mood with the gel” (couples' group). A woman commented that with the gel, there was “more desire, more touching” (women's group). Another man said, “Men feel aroused when they see women insert the gel” (couples' group).

In the men's groups, there were discussions about whether the gel delayed ejaculation; some men felt that there was no difference when using the gel, while others said that the gel enabled them to have sex for longer durations:

Personally I think it's good. I observed when we used it and when we didn't. Usually when I have sex with my wife, people of our age, it lasts 15 to 20 minutes. Using the gel helps it last longer, half an hour or so. So it's great, put the gel on and don't have to think about anything, just do it [men's group].

One female respondent commented that the gel delayed her orgasm.

There was some variability among men and women about whether sexual frequency increased while using the gel. Some respondents felt that sexual frequency increased significantly: “It's good. Some people got really excited because they had more sex when they used the gel. It's like jumping from two to five times straight” (men's group); “we like it because we had sex more often when we used the gel” (women's group). However, in all groups, some respondents said that sexual frequency stayed the same with gel use. No respondents said that sexual frequency decreased while using the gel.

Partner dynamics and product use

When asked about who might use microbicides in real life, most participants focused on issues of fidelity, trust, and communication within relationships. In all groups, the majority of participants felt that gel use would probably be unnecessary among married couples: “If both of us were honest with each other, then there's no need to use it” (men's group). Nearly all respondents agreed that if one partner wanted to use the gel, then both partners would have to discuss the reasons why, in order to avoid arguments or suspicions:

We must talk if she wants to use the gel. I would be worried if we have problems because I believe I'm innocent. I wouldn't understand her need to use it. Doesn't she trust me? How many years have we been together [men's group]?

While most female respondents said that they would buy and use the gel only when they “doubted” their husbands, a few felt that “knowing” their partners was not enough. “It's not about knowing him. … Never underestimate men's behavior,” noted one woman (women's group). There was an understanding among respondents in all groups that men are more likely to “misbehave” when they go out with their friends and drink, and that they are likely to have casual sex when they travel or migrate for work. Accordingly, one woman felt that microbicides might be appropriate for married couples in which one partner migrates for work: “If one of us traveled to another place for work and stayed away for long time, we should use it as a precaution” (couples' group).

All groups discussed the possibility of a woman using the gel covertly. These discussions focused on whether women could use the gel without their partners feeling it physically and whether it was appropriate for them to do so. Participants delivered mixed responses about whether men would be able to detect gel use by their female partners. Nearly all respondents felt that it would be impossible for married couples to conceal use. A woman explained: “He would know [if I used the gel]. It's sticky and thicker without the gel. With the gel it's thinner and clearer” (couples' group). In this case, the woman is referring to her vaginal lubrication. Similarly, a man explained that he “knew [when she used the gel] because it was smooth when we had sex” (couples' group). Here again, the “it” refers to vaginal lubrication. Yet during discussions about hypothetical scenarios in which men were asked to consider using the gel instead of condoms, a number of men indicated that they might not know if women had inserted the gel. For example, a male respondent said that he would still use condoms even if his partner had assured him that she had inserted the gel and he had seen the empty applicator tube, because he still could not be certain that his partner was telling the truth (from a men's group).

Several male respondents seemed to resent the idea that their partners might conceal gel use, suggesting that it would be an indication of mistrust or infidelity in the relationship. Some men, however, saw the gel as something for women to use, just as men rely on condoms, and liked the idea of women having their own method of protection: “It's good; I can go out because my wife has protection” (men's group). There was also an acknowledgment that women are not always able to negotiate condom use with their partners and that they could still protect themselves by using the gel: “If they wanted me to use condoms and I refused, they can't do anything about it or force me to do it. They must protect themselves” (men's group).

Impact on risk behavior

Many men and women expressed concern that if the gel was found effective and made available to consumers, there might be an increase in sexual promiscuity and infidelity. Nearly all participants felt that men would be more likely to seek out casual partners and less likely to use condoms if microbicides were available. One woman explained, “They don't really go out much right now because they're afraid. With this gel, there's no stopping them” (women's group). A man from a couples' group reiterated this sentiment, saying, “Now I don't [misbehave], but in the future I might risk more” (couples' group). One female participant, however, felt that the availability of microbicides might negatively impact women's behavior more than men's, since the roles of who controls the method of protection would be reversed:

I don't think men would change. It would be women, especially students. They would be twice as bad because they're the ones who would use the gel. Men would be worried if women didn't use it. Women would have freedom to use it and it's easy to carry around [women's group].

Product promotion and marketing

In general, most participants felt that the gel should be made widely available. Participants identified several populations that might be interested in using the gel. Both men and women identified sex workers as good candidates for gel use, since not all sex workers are successful in convincing their clients to use condoms:

I used to ask prostitutes [how they protected themselves], and they said only a few people use condoms. The drunken ones especially wouldn't use anything at all. If women handed out condoms, they would refuse, saying they prefer the natural way [women's group].

One man suggested that brothels institute policies for gel use, the way that some currently do with condoms, and advertise that they offer safe services. A few respondents also said that young people, students, migrants, newlyweds, and widows might use the gel, since all of these groups are perceived to have multiple partners or be at high-risk for HIV and STIs. These respondents added that older women who experience vaginal dryness might choose to use the gel for its lubricating properties.

Discussions about practical use of the gel were often framed in comparison to condoms. Many respondents said they were “fed up” with using condoms because they are unnatural, expire, are difficult to put on and take off, require disposal, and often “spoil the mood.” The gel, in contrast, was perceived to be smooth, easy to use, and more natural and reliable than condoms. Most men and women said that they would prefer the gel to condoms if it were available: “If we had the gel, condoms would be out of the question” (men's group).

Most women were particularly interested in the possibility of the gel's having contraceptive properties. Several women complained about using oral contraceptives, saying, “Some people get dizzy on contraceptive pills, and [it's] annoying with always having to change brands” (women's group). These women felt that if the gel could be used as a contraceptive, they might use it instead of their current methods: “Even better; we wouldn't have to take pills; there would be no need for needles” (women's group).

Many respondents thought that the gel should be moderately priced—not prohibitively expensive, but also not so cheap as to cause people to question its quality: “It would have a negative effect if it were 10 baht (∼$0.27). People would wonder if it really prevented AIDS because even a basket of fish costs more” (men's group). In one discussion in a men's group, several participants suggested that the gel cost 50 baht (∼$1.34) per tube. They estimated that since condoms cost approximately 40 baht for a box of three, and because many people use two to three condoms per sex act to protect themselves in case one breaks, a 50-baht tube of gel would be roughly equivalent.

Discussion

This is the first microbicide acceptability study to enroll couples and report on men's and women's experiences of using a candidate product together. Couples studies are unique in that they provide insight into relationship dynamics and communication issues surrounding sex, trust, and product use.

The majority of women and men who participated in these focus groups found the gel acceptable and thought that it should be made widely available. Men and women both thought that the gel was messy but also noted that the gel enhanced sexual pleasure; this sentiment was also expressed during structured interviews conducted as part of the trial, in which 66% of women and 72% of men reported that the gel increased sexual pleasure.³⁵ During the focus groups, many participants acknowledged that if a microbicide is found effective at preventing disease, they would be more likely to accept some of the less appealing qualities, such as the messiness. Relatedly, some participants reported inserting only half of the product in the applicator prior to sex and recommended reducing the quantity before finally approving the product for public sale. The implication was that decreasing the volume would improve uptake of any new product.

Participants enrolled in this study overwhelmingly liked the lubrication provided by the product; the microbicide acceptability literature, however, reports diverse preferences about vaginal lubrication.³⁶ A recent study from Rwanda reported results similar to ours; researchers found that both men and women value vaginal lubrication in general, and respondents reported that increased lubrication from a microbicide would be advantageous.³⁷ Female participants in other studies have also reported that use of a microbicide would increase their own or their partners' sexual pleasure.^21,26,29 However, in one South African study, two thirds of men said that they would not like a microbicide to increase vaginal lubrication,²³ and in another, participants confirmed that increased vaginal lubrication was a problem because it might signify that the woman had recently had sex with another man.²⁸ Zimbabwean men have also reported that “wet sex” reduces pleasure and warned that microbicides should not increase lubrication because “the women who use it might be thrown out of their homes.”²⁴ Indeed, much has been written about cultural preferences for “dry sex,”^38
–40 and many women's health advocates worry that increased lubrication will decrease acceptability of microbicides in some contexts and make it difficult for women to use them covertly. Accordingly, potential microbicide marketing strategies must take local attitudes toward vaginal lubrication into consideration.

The issue of fidelity within relationships was pervasive in this study. As has also been reported in previous research, women and men in our study expressed contrasting viewpoints at times about the issue of covert use and whether a woman has a right to protect herself without informing her partner. It is clear that communication about sex, disease prevention, and contraception is difficult for couples, because it is intimately tied to issues of fidelity and trust within the relationship.^{5,21
–23,24,26–27} Participants in our study, as has been reported by others, noted both the need for women to have ways to protect themselves and concerns about women's fidelity that may come with providing greater protection.^5,21

The majority of participants in our study felt that women should consult their partners before using microbicides, and nearly all women felt that covert use would be unnecessary or inappropriate in their relationships. Yet some women invariably will want or need to hide the use of microbicides from their partners. Nearly all participants, male and female, in our study expressed conflicting opinions about whether it would be feasible for a woman to use a microbicide discretely; however, most believed covert use would not be possible. This assessment is inconsistent with participant responses to monthly acceptability questions that were part of the clinical trial. Although only 15% of women said that they thought that they could use the gel covertly, 43% of men believed that their partners could use it without their noticing.³⁵ The discrepancy between these findings may be because of differences in reporting across interview modes or different understanding of the questions.

Results from this study should be considered in light of its limitations. First, all focus groups, including those that included men only, were moderated by women. We cannot evaluate whether the men's responses might have been different, or whether different issues would have come up, with male moderators. Second, of the 52 couples who participated in the clinical trial, only 21 couples (40% ) and 9 individuals (51/104—49%) took part in the focus groups. These couples/individuals may not be representative of the trial participants, and it is plausible that couples/individuals who had better experiences with using the gel or participating in the study were more likely to agree to participate. It is equally plausible that those who participated in our focus groups had the most negative experiences. Our results also apply to couples who were willing to join a clinical trial, which may also be an indicator of greater couple communication, and these results may not be generalizable to other couples. Finally, we are unable to determine the saturation of the data, since we were only able to form two focus groups for each stratification.

In thinking about how to effectively introduce a potential microbicide so that it has the greatest impact on the HIV epidemic, it is important to consider some of the pitfalls of the condom marketing strategy as well as the target population. Although condoms have been successfully marketed as a method of reducing HIV and STI transmission among sex workers in Thailand,^41
–43 that strategy may not be compelling to nonprostitute populations, such as married couples or young people. The present condom marketing strategy does not address the fact that many people perceive condoms as reducing pleasure and that their use has been unsuccessful for certain populations, particularly married couples or monogamous partners for whom their use has come to signify distrust or infidelity. Men in many different contexts overwhelmingly support condom use with prostitutes or girlfriends, but not with their wives, which makes marriage a risk factor for HIV acquisition for women.^44

–47 The ideal HIV prevention strategy for microbicides is use in concert with condoms. The key to successfully marketing microbicides, should they be found effective, will be to craft unique messages appropriate for different population groups. For sex workers, the strategy may be to focus on disease prevention combined with a message of increased pleasure for customers. However, for married couples, monogamous partners, or other nonprostitute groups, marketing microbicides as contraceptives, as a way to increase sexual pleasure (as also concluded by Whitehead et al.³⁵), or as an occasional method that women can use without their partners' active participation may be more effective.²⁸

Footnotes

Disclosure Statement

The authors have no conflicts of interest to report.

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