The purpose of this study was to compare gait patterns during pregnancy. Because of the changes in hormone levels and anatomical changes such as body mass, body-mass distribution, joint laxity, and musculotendinous strength that result from pregnancy, it was possible that there would be certain gait deviations associated with these changes. Three-dimensional gait analyses were performed from a self-selected pace, and six subjects(height : $163{\pm}5.3cm$, mass : $61.3{\pm}3.80kg$, $65.3{\pm}5.14kg$, $70.2{\pm}4.98kg$) participated in the three times(the early, middle and last years). 7 cameras(Proreflex MCU-240, Qualisys) and 2 force plates (Type 9286AA, Kistler) were used to acquire raw data. The parameters were calculated and analyzed with Visual-3D and Joint moments computed using inverse dynamics. In conclusion, pregnant women's gait patterns were changed during pregnancy period because pregnancy makes them physical changes. The main changes were joint moments and kinematic factors during pregnancy period. The pregnancy transformed normal gait pattern Into toe out position. Therefore, exercise programs to improve muscle activity were necessary where joint moments were small. The development of simulator should be studied for pregnant women's tailored shoes and accessories in future.