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Effectiveness of female and male condoms in preventing exposure to semen during vaginal intercourse: a randomized
Loren W Galvão1, Laurione C Oliveira, Juan Díaz
1Population Council, Campinas, 13083-745, Brazil. lgalvao@uwm.edu
Objectives:
Comparison of male condom (MC) vs. female condom (FC) with respect to self-reported mechanical and acceptability problems and semen exposure using prostate-specific antigen (PSA) as an objective biological marker and evaluation of the effect of an educational intervention on self-reported problems and semen exposure, by condom type.
Design:
Randomized crossover trial.
Methods:
Four hundred women attending a family planning clinic in Brazil were randomized and either received in-clinic instruction or were encouraged to read the condom package insert; all used two FCs and two MCs. We measured the rates of self-reported user problems with MC and FC use and the rates of semen exposure during use (assessed by testing vaginal fluid for PSA).
Results:
The educational intervention group reported fewer problems with either condom as compared with the control group (p = .0004, stratified by condom type). In both groups, self-reported problems were more frequent with FC use than with MC use (p < .0001, stratified by intervention). The educational intervention did not significantly reduce semen exposure. Overall, semen exposure occurred more frequently with FC use (postcoital PSA, > 1 ng/mL; 22%) than with MC use (15%); the difference, however, was small and nonsignificant for high PSA levels (> or = 150 ng/mL; 5.1% for FC vs. 3.6% for MC).
Conclusions:
In this study, the FC was less effective than the MC in preventing semen exposure during use and led more frequently to self-reported user problems. Both devices were highly protective against "high-level" semen exposure, as measured by postcoital PSA levels in vaginal fluid. In-clinic education may reduce user problems and increase acceptability and use of both devices.
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