Pregnant women with mechanical prosthetic heart valves (MPHV) have adverse effects on the growth and development of the fetus. Data on MPHV pregnant women and their offspring from our hospital from 2014 to 2020 were retrospectively collected. There were 137 pregnancies, 96 in the warfarin group, 28 in the low-molecular-weight heparin (LMWH) group, 13 in the sequential treatment group. There are 27 cases of spontaneous abortion, 3 cases of stillbirth, 56 live births and 51 artificial abortion. The international normalized ratio (INR, P < 0.001), prothrombin time (PT, P = 0.014), activated partial thromboplastin time (APTT, P = 0.035) of the neonates in the warfarin group were increased compared with the other two groups. Multivariate Tobit regression analysis showed that the probability of spontaneous abortion/stillbirth was positively correlated with INR before delivery (OR 1.13, P = 0.009) and valve usage time (OR 1.13, P = 0.009). The probability of malformation was positively correlated with worse heart function level (OR 1.20, P = 0.025) and INR (OR 1.18, P = 0.011) before delivery. The offspring of MPHV pregnant women who continuously take warfarin have poor outcomes and a significantly higher risk of early bleeding. Prenatal consultations for MPHV women should be strengthened to avoid unplanned pregnancy.