Objective: To investigate the clinical manifestations and laboratory indicators of anti-Sjögren's-syndrome-related antigen A (SSA) antibody associated fetal cardiac disease. Methods: Pregnant women hospitalized at Peking University People's Hospital from January 2013 to July 2023 were included. Eleven patients with anti-SSA antibody positive were eventually diagnosed with fetal cardiac di-sease. And patients with anti-SSA antibody positive without fetal cardiac disease were selected as controls. Clinical manifestations, laboratory indications and drug usage were compared between the two groups. Results: Among these 11 patients, congenital heart block was confirmed in seven, which was the most common manifestations of fetal cardiac malformation. The proportion of the patients diagnosed with autoimmune disease before pregnancy in fetal cardiac malformation group was significantly lower than that in the control group (P=0.032), while most of the patients in the fetal cardiac malformation group received immune-related examinations for the first time because of this time's fetal cardiac diagnosis. While most of the patients in the control group received routine examinations because of autoimmune diseases diagnosed before pregnancy. During pregnancy, the white blood cell level [(9.29±2.58)×10⁹/L vs. (7.10±1.90×10⁹/L, t=3.052, P=0.004], erythrocyte sedimentation rate [(49.50 (48.00, 51.00) mm/h vs. 23.00 (15.00, 30.25) mm/h, Z=-2.251, P=0.024], IgA level [3.46 (2.30, 5.06) g/L vs. 2.13 (1.77, 2.77) g/L, Z=-2.181, P=0.029], and antinuclear antibody (ANA) titers [1∶320 (1∶160, 1∶320) vs. 1∶80 (1∶40, 1∶160), Z=-3.022, P=0.003] were significantly higher in fetal cardiac malformation group than in the control group. The proportion of positive anti-SSB antibody during pregnancy did not show a statistically significant difference between the two groups (37.5% vs. 7.7%, P=0.053). There was no significant difference in hydroxychloroquine dosage and initiation time between the two groups. The dosage of prednisone in the second and third trimesters was significantly higher in the cardiac malformation group than that in the control group, but there was no significant difference in the first trimester. Conclusion: Fetal cardiac disease is rare in pregnant women with anti-SSA antibody. White blood cell, erythrocyte sedimentation rate, IgA, the titer of ANA positivity were higher in the fetal heart disease group during pregnancy. Since congenital heart block is difficult to reverse, its prevention and monitoring are more important than remedial treatment.