***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objective The objective of this trial was to determine the effectiveness of 1.0 % C31 G ( SAVVY ) in preventing male-to-female vaginal transmission of HIV infection among women at high risk . Methodology /Principal Findings This was a Phase 3 , double-blind , r and omized , placebo-controlled trial . Participants made up to 12 monthly visits for HIV testing , adverse event reporting , and study product supply . The study was conducted between March 2004 and February 2006 in Accra and Kumasi , Ghana . We enrolled 2142 HIV-negative women at high risk of HIV infection , and r and omized them to SAVVY or placebo gel . Main outcome measures were the incidence of HIV-1 and HIV-2 infection as determined by detection of HIV antibodies from oral mucosal transu date specimens and adverse events . We accrued 790 person-years of follow-up in the SAVVY group and 772 person-years in the placebo group . No clinical ly significant differences in the overall frequency of adverse events , abnormal pelvic examination findings , or abnormal laboratory results were seen between treatment groups . However , more participants in the SAVVY group reported reproductive tract adverse events than in the placebo group ( 13.0 % versus 9.4 % ) . Seventeen HIV seroconversions occurred ; eight in participants r and omized to SAVVY and nine in participants receiving placebo . The Kaplan-Meier estimates of the cumulative probability of HIV infection through 12 months were 0.010 in the SAVVY group and 0.011 in the placebo group ( p = 0.731 ) , with a hazard ratio ( SAVVY versus placebo ) of 0.88 ( 95 % confidence interval 0.33 , 2.27 ) . Because of a lower-than-expected HIV incidence , we were unable to achieve the required number of HIV infections ( 66 ) to obtain the desired study power . Conclusions / Significance SAVVY was not associated with increased adverse events overall , but was associated with higher reporting of reproductive adverse events . Our data are insufficient to conclude whether SAVVY is effective at preventing HIV infection relative to placebo . Trial Registration Clinical Trials.gov 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 Summary Background Innovative prevention strategies for HIV-1 transmission are urgently needed . PRO2000 vaginal gel was efficacious against HIV-1 transmission in studies in macaques ; we aim ed to assess efficacy and safety of 2 % and 0·5 % PRO2000 gels against vaginal HIV-1 transmission in women in sub-Saharan Africa . Methods Microbicides Development Programme 301 was a phase 3 , r and omised , double-blind , parallel-group trial , undertaken at 13 clinics in South Africa , Tanzania , Ug and a , and Zambia . We r and omly assigned sexually active women , aged 18 years or older ( ≥16 years in Tanzania and Ug and a ) without HIV-1 infection in a 1:1:1 ratio  to 2 % PRO2000 , 0·5 % PRO2000 , or placebo gel groups for 52 weeks ( up to 104 weeks in Ug and a ) . R and omisation was done by computerised r and om number generator . Investigators and participants were masked to group assignment . The primary efficacy outcome was incidence of HIV-1 infection before week 52 , which was censored for pregnancy and excluded participants without HIV-1 follow-up data or with HIV-1 infection at enrolment . HIV-1 status was established by rapid tests or ELISA at screening at 12 weeks , 24 weeks , 40 weeks , and 52 weeks , and confirmed in a central reference laboratory . The primary safety endpoint was an adverse event of grade 3 or worse . Use of 2 % PRO2000 gel was discontinued on Feb 14 , 2008 , on the recommendation of the Independent Data Monitoring Committee because of low probability of benefit . This trial is registered at http://is rct n.org , number IS RCT N 64716212 . Findings We enrolled 9385 of 15 818 women screened . 2591 ( 95 % ) of 2734 participants enrolled to the 2 % PRO2000 group , 3156 ( 95 % ) of 3326 in the 0·5 % PRO2000 group , and 3112 ( 94 % ) of 3325 in the placebo group were included in the primary efficacy analysis . Mean reported gel use at last sex act was 89 % ( 95 % CI 86–91 ) . HIV-1 incidence was much the same between groups at study end ( incidence per 100 woman-years was 4·5 [ 95 % CI 3·8–5·4 ] for 0·5 % PRO2000 vs 4·3 [ 3·6–5·2 ] for placebo , hazard ratio 1·05 [ 0·82–1·34 ] , p=0·71 ) , and at discontinuation ( 4·7 [ 3·8–5·8 ] for 2 % PRO2000 gel , 3·9 [ 3·0–4·9 ] for 0·5 % PRO2000 gel , and 3·9 [ 3·1–5·0 ] for placebo gel ) . Incidence of the primary safety endpoint at study end was 4·6 per 100 woman-years ( 95 % CI 3·9–5·4 ) in the 0·5 % PRO2000 group and 3·9 ( 3·2–4·6 ) in the placebo group ; and was 4·5 ( 3·7–5·5 ) in the 2 % PRO2000 group at discontinuation . Interpretation Although safe , 0·5 % PRO2000 and 2 % PRO2000 are not efficacious against vaginal HIV-1 transmission and are not indicated for this use . Funding UK Department for International Development , UK Medical Research Council , European and Developing Countries Clinical Trials Partnership , International Partnership for Microbicides , and Endo Pharmaceuticals Solutions OBJECTIVE : Women who become pregnant during the conduct of biomedical human immunodeficiency virus prevention trials are taken off the study product for safety reasons . High pregnancy rates can compromise statistical integrity in these trials . The comprehensive contraceptive curriculum developed for the Centre for the AIDS Programme of Research in South Africa ( CAPRISA ) 004 trial was evaluated for its ability to enhance contraceptive uptake , reduce pregnancy rates , and preserve statistical integrity . METHODS : Contraceptive- and pregnancy-related eligibility criteria were specified in the protocol . We enrolled women who opted for a nonbarrier method of contraceptive and provided hormonal contraceptives onsite at no cost .  At each monthly study visit , we provided pregnancy prevention counseling and performed pregnancy testing . Study product was withheld on pregnancy diagnosis , but women continued with monthly follow-up . RESULTS : Contraceptive use was high throughout the study with 100 % uptake at baseline and 94.71 % use after a mean of 18 months follow-up at exit . Injectable progestins , particularly medroxyprogesterone acetate , remained the preferred choice of contraceptive . After 30 months of follow-up , 54 pregnancies were reported out of 889 participants , giving a pregnancy incidence rate of 3.95 per 100 woman-years ( 95 % confidence interval 2.96–5.17 ) . Of all pregnancies , two thirds ( 64.81 % ) result ed in a full-term live birth , whereas 18.52 % and 11.11 % pregnancies culminated as miscarriage and terminated pregnancies , respectively . There were no congenital anomalies in the early neonatal period . Pregnancies result ed in 1.56 % of woman-years of study follow-up lost as a result of temporary product withdrawal . CONCLUSION : The CAPRISA 004 contraceptive curriculum was an effective strategy for maintaining low pregnancy rates , thereby minimizing product withdrawal and loss of follow-up time . LEVEL OF EVIDENCE : Background This trial evaluated the safety and effectiveness of 6 % cellulose sulfate vaginal gel in preventing male-to-female vaginal transmission of HIV , gonorrhea and chlamydial infection . Methods This Phase III , double-blind , r and omized , placebo-controlled trial was conducted between November 2004 and March 2007 in Lagos and Port Harcourt , Nigeria . We enrolled 1644 HIV-antibody negative women at high risk of HIV acquisition . Study participants were r and omized 1∶1 to cellulose sulfate or placebo  and asked to use gel plus a condom for each act of vaginal intercourse over one year of follow-up . The participants were evaluated monthly for HIV , gonorrhea and chlamydial infection , and for adverse events . Results The trial was stopped prematurely after the data safety monitoring board of a parallel trial concluded that cellulose sulfate might be increasing the risk of HIV . In contrast , we observed fewer infections in the active arm ( 10 ) than on placebo ( 13 ) , a difference that was nonetheless not statistically significant ( HR = 0.8 , 95 % CI 0.3–1.8 ; p = 0.56 ) . Rates of gonorrhea and chlamydial infection were lower in the CS group but the difference was likewise not statistically significant ( HR = 0.8 , 95 % CI 0.5–1.1 ; p = 0.19 for the combined STI outcome ) . Rates of adverse events were similar across study arms . No serious adverse events related to cellulose sulfate use were reported . Conclusions Cellulose sulfate gel appeared to be safe in the evaluated study population but we found insufficient evidence that it prevented male-to-female vaginal transmission of HIV , gonorrhea or chlamydial infection . The early closure of the trial compromised the ability to draw definitive conclusions about the effectiveness of cellulose sulfate against HIV . Trial Registration Clinical Trials.gov Vaginal Gel Versus HIV HIV prevention technologies for women are urgently needed , especially in sub-Saharan Africa where young women bear the greatest burden of the HIV epidemic . 
    Output:
    
Hormonal injectable , intra-uterine device ( IUD ) or implants or sterilization , older age , more years of education and condom use were associated with lower pregnancy .
On the other h and , living with a man , history of pregnancy , self and partner desire for future baby , oral contraceptive use , increased number of unprotected sexual acts and inconsistent use of condoms were associated with higher pregnancy .