Pregnancy and fetal outcomes following maternal exposure to glatiramer acetate in all three trimesters of pregnancy.

Background And Purpose: Data on disease-modifying therapy (DMT) exposure throughout pregnancy in patients with multiple sclerosis are scarce. In this analysis, we assessed pregnancy and fetal outcomes following maternal glatiramer acetate (GA) exposure in all three trimesters among cases reported between 1997 and 2020.

Methods: Pregnancy reports of maternal in utero exposure to 20 and 40 mg/mL GA in all three trimesters from 1997 to 2020 were eligible. Both prospective pregnancy data, reported prior to knowledge of pregnancy outcome, and retrospective data were included. The primary endpoint was major congenital malformations (MCMs) based on the European Surveillance of Congenital Anomalies and Twins (EUROCAT) classification. Additional endpoints included fetal death, preterm birth, and low birth weight. The MCM rate was compared to the EUROCAT background rate.

Results: A total of 618 GA-exposed pregnancies in all three trimesters resulted in 634 fetuses, including 14 twin pregnancies. One fetal death was reported. All 414 fetuses with data reported prior to knowledge of pregnancy outcome (prospective data) were live births and no fetal death was reported. Preterm birth was reported in 23/213 (10.8%) pregnancies with known gestational age. Low birth weight was reported in 13/203 (6.4%) infants with known birth weight. The prevalence of MCM in prospective live births ranged from 2.2% to 2.4%, which was similar to background rates (2.1%-3.0%). The frequency of these pregnancy and infant outcomes was comparable across GA doses.

Conclusions: In utero exposure to 20 and 40 mg/mL GA in three trimesters of pregnancy does not appear to be related to adverse pregnancy or infant outcomes.