Valvular heart disease (VHD) accounts for significant morbidity and mortality during pregnancy, with limited data to guide cardio-obstetric risks. This is a retrospective cohort study describing maternal, obstetric, and fetal outcomes of Kaiser Permanente Northern California members with VHD during pregnancies between 2010 and 2021. Adult patients with moderate to severe native VHD and/or previous valve interventions were included. There were 242,066 eligible pregnancies in the study period, 89 (0.04%) of which were complicated by clinically significant VHD: 25 with pulmonary stenosis/regurgitation, 40 with aortic/mitral regurgitation, 18 with aortic/mitral stenosis, and 6 with mixed/other VHD. Forty-eight had native VHD, and 41 had previous percutaneous/surgical valve intervention. Adverse maternal outcomes were rare in pulmonary stenosis/regurgitation patients, but preeclampsia/eclampsia was observed in 20%, and C-section in 36%. In those with aortic/mitral regurgitation, congestive heart failure hospitalizations occurred in 10%, preeclampsia/eclampsia in 22.5%, preterm delivery in 25%, and C-section in 32.5%. In those with aortic/mitral stenosis, 5.6% had congestive heart failure hospitalizations, 22% had C-section, 22% were preterm with 27.8% infants requiring neonatal intensive care unit stay. One maternal death occurred in a patient with MR with concomitant long QT syndrome. In this contemporary pregnancy cohort, regurgitant lesions were most prevalent and associated with significant maternal morbidity. In conclusion, this study highlights that left-sided valvular regurgitant lesions during pregnancy, in addition to stenotic lesions, are associated with significant morbidity.