Objectives Percutaneous balloon mitral valvuloplasty (PBMV) is one way to improve the rheumatic mitral stenosis. How does the procedure work in gravida and fetus is not very clear. We analyzed the effects and safety of PBMV operation on pregnant patients with severe rheumatic mitral stenosis. Methods Eight pregnant patients suffering from severe mitral stenosis underwent facilitated PBMV operation with Inoue balloon, and were followed up for (2.0±1.1) years. Contents included outcome of pregnancy, infant growth, hemodynamics, echocardiography, cardiac function, mitral valves replacement or repeat valvuloplasty. Results Mitral valve area (MVA) before, one week and one year after facilitated PBMV were (0.84±0.21) cm2, (1.69±0.23) cm2 and (1.51±0.24) cm2 respectively. The transmitral pressure gradient dropped from (22.1±4.7) mm Hg to (9.9±3.1) mm Hg (P<0.001) (1 mm Hg=0.133 kPa). After facilitated PBMV, all patients showed remarkable immediate symptomatic and hemodynamic improvement without severe mitral regurgitation. All of these patients could maintain New York heart association (NYHA) Ⅰ or Ⅱ for (2. 0±1.1) years after the operation. Two patients demanded induced abortion concerning about the teratogenic effect of X-ray on fetus. All the other six patients continued their gestation and had full-term cesarean section without complications. Their newborns developed healthy and normally till now. Conclusions Facilitated PBMV is a feasible, safe and effective device for selected pregnant patients with mitral stenosis. The operation is well tolerated by the fetus. Objectives Percutaneous balloon mitral valvuloplasty (PBMV) is one way to improve the rheumatic mitral stenosis. How does the procedure work in gravida and fetus is not very clear. Methods Eight pregnant patients suffering from severe mitral stenosis underwent facilitated PBMV operation with Inoue balloon, and were followed up for (2.0 ± 1.1) years. Contents included outcome of pregnancy, infant growth, hemodynamics, echocardiography, cardiac function, mitral valves replacement or repeat valvuloplasty. Results Mitral valve area (MVA) before, one week and one year after facilitated PBMV were (0.84 ± 0.21) cm2, (1.69 ± 0.23) cm2 and (1.51 ± 0.24) ± 4.7) mm Hg to (9.9 ± 3.1) mm Hg (P <0.001) (1 mm Hg = 0.133 kPa). After facilitated PBMV, all patients showed remarkable immediate symptomatic and hemodynamic improvement All patients who were unable to maintain the New York Heart Association (NYHA) Ⅰ or Ⅱ for (2.0 ± 1.1) years after the operation. Two patients demanded induced abortion concerning about the teratogenic effect of X-ray on fetus All the other six patients continued their gestation and had full-term cesarean section without complications. Their newborns developed healthy and normally till now. Conclusions Facilitated PBMV is a feasible, safe and effective device for selected pregnant patients with mitral stenosis. The operation is well tolerated by the fetus.