Backgraound: Presently, there is no apparent agreement on the effects of pregnancy on the durability of bioprosthetic valves (BPV). The study aim was firstly to assess the influence of pregnancy on survival of BPV; secondly, maternal and fetal outcomes of pregnancy with BPV.Methods: Between 1981-2008, of the total patients selected, 31 were assigned to the bioprosthetic valve replacement group who became pregnant (39 pregnancy) after surgery [PAS (+)]; a group of 26 bioprosthetic valve replacement patients were also included whom did not experience pregnancy till the time of study [PAS (-)].We obtained information on type of repaired valves, outcome of pregnancies and valve surgery related complications survey of the patients by reviewing the follow up files of centers.Results: The mean age of PAS (+) and PAS (+) subjects was 32.19 ± 4.42 (max=45, min=24) years and 33.93 ± 6.58 (max=43, min=23) respectively (p>0.05). Gehan test shown that there wasn’t significant relation between valves durability in two groups (P= 0.22 ،df = 1 ،χ 2 =1.49, diagram 1). Reoperation rate, mortality rate between case PAS (+) and PAS (-) was not significantly different (p>0.05). Live births were recorded in 30 (76.9%) of pregnancies (1 fetal death). The average of newborns weight was 2200.32 ± 1116.6 gr. Upon our findings 21(70.0%) of newborns were term and 10(30.0%) were preterm.Conclusion: Although pregnancy does not have a significant influence on structural depreciation of bioprosthetic valves survival and maternal mortality, bioprosthetic valves might be associated with birth defects.