Using a specific myofibroblast contraction test, we try to predict future utero-vaginal prolapse development in young primiparae women. We compare myofibroblast cultures of the vaginal wall in primiparae women (group 1), young multiparae women (group 2) and older multiparae women (group 3) who were operated on for severe utero-vaginal prolapse. A myofibroblast-mediated collagen gel contraction assay determined a contraction factor that was compared in the three groups of women. The myofibroblasts contraction factor after 24 and 48 hours was significantly higher in group 1 women (2.4 +/- 0.6/4.4 +/- 1.9) compared to group 2 (1.6 +/- 0.3/ 1.8 +/- 0.1) andgroup 3 (1.6 +/- 0.3/1.8 +/- 0.3), but showed no differences in group 1 women without (2.1 +/- 0.5/3.5 +/- 1.9) and with (2.7 +/- 0.6/5.1 +/- 1.7) cystocoele. Vaginal myofibroblasts of young women show better contraction forces than young women with severe utero-vaginal prolapse. The latter have a myofibroblast contraction factor similar to those of older post-menopausal women operated for the same condition.