To assess how maternal B-cell–depleting therapy (BCDT) influences early maternal and infant health outcomes.

The UCSF PRISMA (Pregnancy Registry, Infants, Serum/Milk Analysis) study prospectively follows pregnant/postpartum women with MS, collecting maternal and newborn data. Here, live-birth pregnancy outcomes were compared for women with pre-conception BCDT (N=65) vs. other-DMT (N=31) vs. No-DMT (N=24) use.

Mean maternal age was 34.8 years, and median EDSS was 1.5; 95% of the infants were breastfed. In the pre-conception BCDT group (median months exposure-conception: 3.7), CD19 counts at delivery/early postpartum were undetectable in 10 (43%), partially recovered in 6 (27%), and completely recovered in 7 (30%).

The primary maternal outcome, proportion of MRIs categorized as “active” in the year postpartum, was substantially lower in the pre-conception BCDT group (6%) vs. Other-DMT (62%)/no-DMT (55%) groups (OR=0.05, p<0.001).

Regarding the offspring outcomes, there were no significant differences according to maternal DMT category (either pre-conception or post-partum) in the proportion of newborns with preterm birth, low birth weight, or low 5-min APGAR scores. Nor was there any difference in the proportion of infants experiencing impaired growth (height, weight, head circumference) or development (ASQ 3) trajectories, or >3 infections, over the first year of life (p>0.05 for all outcomes).

Prospectively collected data confirm the protective effect of BCDTs in abrogating postpartum inflammatory injury, without an apparent increase in newborn or infant risks over the first year of life. While continued follow-up up to 5 years is warranted, these findings support use of BCDTs as a proactive management strategy for women with MS throughout the peripartum period.