***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: BACKGROUND Female-initiated HIV-prevention options , such as microbicides , are urgently needed . We assessed Carraguard , a carrageenan-based compound developed by the Population Council , for its efficacy and long-term safety in prevention of HIV infection in women . METHODS We undertook a r and omised , placebo-controlled , double-blind trial in three South African sites in sexually-active , HIV-negative women , aged 16 years and older . 6202 participants , who were r and omly assigned by a block r and omisation scheme to Carraguard ( n=3103 ) or placebo ( methylcellulose [ n=3099 ] ) , were instructed to use one applicator of gel plus a condom during each vaginal sex act . Participants were followed up for up to 2 years . Visits every 3 months included testing for HIV presence and pregnancy , pelvic examinations , risk reduction counselling , and treatment for curable sexually transmitted infections and symptomatic vaginal infections . The primary outcome was time to HIV seroconversion . Analysis was in the efficacy population ( a subset of the intention-to-treat population , excluding participants for whom efficacy could not be assessed ) . This study is registered with Clinical Trials.gov , number NCT00213083 . FINDINGS For the primary outcome ( time to HIV seroconversion ) we analysed 3011 women in the Carraguard group and 2994 in the placebo group .  HIV incidence was 3.3 per 100 woman-years ( 95 % CI 2.8 - 3.9 ) in the Carraguard group ( 134 events ) and 3.8 per 100 woman-years ( 95 % CI 3.2 - 4.4 ) in the placebo group ( 151 events ) , with no significant difference in the distribution of time to seroconversion ( p=0.30 ) . The covariate-adjusted hazard ratio was 0.87 ( 95 % CI 0.69 - 1.09 ) . Rates of self-reported gel use ( 96.2 % Carraguard , 95.9 % placebo ) and condom use ( 64.1 % in both groups ) at last sex acts were similar in both groups . On the basis of applicator testing , however , gel was estimated to have been used in only 42.1 % of sex acts , on average ( 41.1 % Carraguard , 43.1 % placebo ) . 1420 ( 23 % ) women in the intention-to-treat population had adverse events ( 713 Carraguard , 707 placebo ) , and 95 ( 2 % ) women had adverse events that were related to gel use ( 48 Carraguard , 47 placebo ) . Serious adverse events occurred in 72 ( 2 % ) women in the Carraguard group and 78 ( 3 % ) in the placebo group , only one of which was considered possibly related to gel use ( placebo group ) . INTERPRETATION This study did not show Carraguard 's efficacy in prevention of vaginal transmission of HIV . No safety concerns were recorded Objectives HIV prevalence among Cambodian female sex workers ( FSW ) is among the highest in Southeast Asia . We describe HIV prevalence and associated risk exposures in FSW sample d serially in Phnom Penh , Cambodia ( Young Women 's Health Study ( YWHS ) ) , before and after the implementation of a new law design ed to combat human trafficking and sexual exploitation . Design Cross-sectional analysis of baseline data from two prospect i ve cohorts . Setting Community-based study in Phnom Penh , Cambodia . Participants Women aged 15–29 years , reporting ≥2 sexual partners in the last month and /or engaged in transactional sex in the last 3 months , were enrolled in the studies in 2007 ( N=161 ; YWHS-1 ) , and 2009 ( N=220 ; YWHS-2 ) following information sessions where 285 and 345 women attended . Primary outcomes HIV prevalence , sexual risk behaviour , amphetamine-type stimulant ( ATS ) and alcohol use , and work-related factors were compared in the two groups , enrolled before and after implementation of the new law . Results Participants in the two cohorts were similar in age ( median 25 years ) , but YWHS-2 women reported fewer sex partners , more alcohol use and less ATS use . A higher proportion of YWHS-2 compared with YWHS-1 women worked in entertainment-based venues ( 68 % vs 31 % , respectively ) . HIV prevalence was significantly lower in the more recently sample d women : 9.2 % ( 95 % CI 4.5 % to 13.8 % ) vs 23 % ( 95 % CI 16.5 % to 29.7 % ) . Conclusions Sex work context and risk have shifted among young FSW in Phnom Penh , following implementation of anti-prostitution and anti-trafficking laws . While both cohorts were recruited using the same eligibility criteria , more recently sample d women had lower prevalence of sexual risk and HIV infection . Women engaging more directly in transactional sex have become harder to sample and access . Future prevention research and programmes need to consider how new policies and demographic changes in FSW impact HIV transmission BACKGROUND The study was conducted to investigate past and future pregnancy preferences and contraceptive need among Malagasy sex workers . STUDY DESIGN We analyzed data on pregnancy and contraceptive use collected during the baseline visit of a r and omized , prospect i ve formative trial which assessed diaphragm and microbicide acceptability among sex workers . To be eligible , women could not be pregnant or planning pregnancy for the next 2 months . RESULTS Women ( N=192 ) from four cities ( Antananarivo , Antsiranana , Mahajanga and Toamasina ) reported a median of 10 sex acts per week . Fifty-two percent reported a prior unwanted pregnancy , 45 % at least one induced abortion and 86 % that preventing future pregnancy was moderately to very important . During the last sex act , 24 % used a hormonal method  , 36 % used a  male condom  , 2 % used a traditional method and 38 % used no  method . Nearly 30 % of participants reported that pregnancy prevention was moderately or very important but used no contraception at last sex ; these women were categorized as having " unmet need " for contraception . In multivariable binomial regression analyses , factors associated with unmet need included low knowledge of contraceptive effectiveness [ age- and site-adjusted prevalence ratio ( PR ) : 2.1 ; 95 % confidence interval ( CI ) : 1.4 - 3.0 ] and low self-efficacy to negotiate condom use ( age- and site-adjusted PR : 2.0 ; 95 % CI : 1.4 - 3.0 ) . CONCLUSIONS Among these women , prior unwanted pregnancy and induced abortion were common and preventing future pregnancy was important , yet gaps in contraceptive use were substantial . Contraceptive knowledge and self-efficacy should be improved to promote contraceptive use by sex workers Background : In preparation for a r and omized controlled trial ( RCT ) , we conducted a pilot RCT of the acceptability and feasibility of diaphragms and c and i date vaginal microbicide for sexually transmitted infection prevention among high-risk women in Madagascar . Methods : Participants were r and omized to four arms : ( 1 ) diaphragm ( worn continuously ) with Acidform ™ applied in the dome ; ( 2 ) diaphragm ( worn continuously ) with placebo gel hydroxyethylcellulose ( HEC ) in the dome ; ( 3 ) HEC applied intravaginally before sex ; ( 4 ) Acidform applied intravaginally before sex . All women were given condoms . Participants were followed weekly for 4 weeks . We fit unadjusted negative binomial regression models with robust variance estimators to generate the proportion of sex acts with casual partners where condoms and experimental study products were used . Results :  Retention  was 98 % among 192 participants .  Experimental product use with casual partners was high , reported in 85 % , 91 % , 74 % , and 81 % of sex acts for women in the Acidform-diaphragm , HEC-diaphragm , HEC-alone , and Acidform-alone arms , respectively . However , the proportion reporting product use during 100 % of acts with casual partners over the full follow-up period was much lower : 28 % to 29 % in the gel-diaphragm arms and 6 % to 10 % in gel-alone arms . Women used condoms in 62 % to 67 % of sex acts with casual partners , depending on the r and omization arm . Participants found diaphragms easy to insert ( 97 % ) and remove ( 96 % ) . Acidform users ( with or without the diaphragm ) reported more genitourinary symptoms than HEC users ( 14 % vs. 5 % of visits ) . Conclusions : A sexually transmitted infection prevention RCT of c and i date microbicide with and without the diaphragm appears acceptable and feasible in this population BACKGROUND The development of a safe and effective vaccine against the human immunodeficiency virus type 1 ( HIV-1 ) is critical to p and emic control . METHODS In a community-based , r and omized , multicenter , double-blind , placebo-controlled efficacy trial , we evaluated four priming injections of a recombinant canarypox vector vaccine ( ALVAC-HIV [ vCP1521 ] ) plus two booster injections of a recombinant glycoprotein 120 subunit vaccine ( AIDSVAX B/E ) . The vaccine and placebo injections were administered to 16,402 healthy men and women between the ages of 18 and 30 years in Rayong and Chon Buri provinces in Thail and . The volunteers , primarily at heterosexual risk for HIV infection , were monitored for the co primary end points : HIV-1 infection and early HIV-1 viremia , at the end of the 6-month vaccination series and every 6 months thereafter for 3 years . RESULTS In the intention-to-treat analysis involving 16,402 subjects , there was a trend toward the prevention of HIV-1 infection among the vaccine recipients , with a vaccine efficacy of 26.4 % ( 95 % confidence interval [ CI ] , -4.0 to 47.9 ; P=0.08 ) . In the per- protocol analysis involving 12,542 subjects , the vaccine efficacy was 26.2 % ( 95 % CI , -13.3 to 51.9 ; P=0.16 ) . In the modified intention-to-treat analysis involving 16,395 subjects ( with the exclusion of 7 subjects who were found to have had HIV-1 infection at baseline ) , the vaccine efficacy was 31.2 % ( 95 % CI , 1.1 to 52.1 ; P=0.04 ) . Vaccination did not affect the degree of viremia or the CD4 + T-cell count in subjects in whom HIV-1 infection was subsequently diagnosed . CONCLUSIONS This ALVAC-HIV and AIDSVAX B/E vaccine regimen may reduce the risk of HIV infection in a community-based population with largely heterosexual risk . Vaccination did not affect the viral load or CD4 + count in subjects with HIV infection . Although the results show only a modest benefit , they offer insight for future research . ( Clinical Trials.gov number , NCT00223080 . Introduction Female sex workers ( FSW ) have high rates of unintended pregnancy , sexually transmitted infections including HIV , and other adverse sexual and reproductive health outcomes . Few services for FSWs include contraception . This mixed- methods study aim ed to determine the rate , predictors and consequences of unintended pregnancy  among FSWs in Mombasa , Kenya . Methods A prospect i ve cohort study of non-pregnant FSWs was conducted . Quantitative data were collected quarterly , including a structured question naire and testing for pregnancy and HIV . Predictors of unintended pregnancy were investigated using multivariate logistic regression . Qualitative data were gathered through focus group discussion s and in-depth interviews with FSWs who became pregnant during the study , and interviews with five key informants . These data were transcribed , translated and analysed thematically . Results Four hundred women were enrolled , with 92 % remaining in the cohort after one year . Fifty-seven percent reported using a  modern contraceptive method ( including condoms when used consistently ) . Over one-third ( 36 % ) of women were using condoms inconsistently without another method . Twenty-four percent had an unintended pregnancy during the study . Younger age , having an emotional partner and using traditional or no contraception , or condoms only , were independent predictors of unintended pregnancy . Women attributed pregnancy to forgetting to use contraception and being pressured not to by clients and emotional partners , as well as “ bad luck ” . They described numerous negative consequences of unintended pregnancy . Conclusion Modern contraceptive uptake is surprisingly low in this at-risk population , which in turn has a high rate of unintended pregnancy . The latter may result in financial hardship , social stigma , risk of ab and onment , or dangerous abortion practice s.  FSWs face considerable barriers to the adoption of dual method contraceptive use , including low levels of control in their emotional and commercial relationships . Reproductive health services need to be incorporated into programs for sexually transmitted infections and HIV , which address the socially-determined barriers to 
    Output:
    
Incidence varied widely , likely due to differences in study design , duration and baseline population risk , but was high in most studies , representing a considerable concern for this key population .