PURPOSE: To describe trends in dispensing of monoclonal antibody biologics (mAbs) for autoimmune conditions during and around pregnancy. METHODS: We conducted a population-wide study of women of reproductive age (14-49 years) resident in Lombardy, Italy, between 2012 and 2024. We described trends over time in the prevalence of mAb dispensations among women of reproductive age, and during pregnancy. For each pregnancy, we assessed the prevalence of mAb dispensations before, during, and after pregnancy in trimesters. We described dispensing patterns and explored maternal factors associated with discontinuation. RESULTS: We included 1 871 929 women of reproductive age and 855 865 pregnancies. Prevalence of mAb dispensing during pregnancy increased over 60-fold over the study period, from 0.0041% in 2012 to 0.27% in 2024. Pregnancy affected mAb dispensing, with prevalence decreasing from 0.081% before pregnancy to 0.051% by the third trimester. Over half (n = 385/722, 53.3%) of pre-existing mAb users discontinued before or during pregnancy, while switching between mAbs during pregnancy was rare (n = 24/722, 3.3%). Discontinuation decreased over time, and varied substantially between mAbs. We found limited evidence that sociodemographic factors were associated with discontinuation, but that some health factors may be, such as use of assisted reproductive technology (OR = 1.92, 95% CI: 0.98-3.77). CONCLUSIONS: Italian population-wide data from 2012 to 2024 show an increase in mAbs dispensed during pregnancy, and fewer instances of discontinuing these drugs over time. These trends may reflect increasing drug availability, accumulating safety evidence, and recent changes in guidelines for mAb use in pregnancy.