Category: Other
Objective: The present study evaluated pregnancy outcomes following onabotulinumtoxinA exposure to provide a cumulative 29-year safety update.
Background: A previous publication of pregnancy outcomes in onabotulinumtoxinA-exposed mothers (Brin et al. Pharmacoepidemiol Drug Saf. 2016;25:179-187) demonstrated that the prevalence of fetal defects (2.7%; 3/110, 95% CI: 0.6-8.0%) was comparable with background rates in the general population.
Method: The Allergan Global Safety Database was searched (1/1/1990-12/31/2018) for onabotulinumtoxinA administration before/during pregnancy for various indications. A conservative approach was taken to minimize reporting bias; only prospective cases were included in prevalence rate estimations (live births and unknown birth types [ie, live vs. fetal loss]). To be conservative, any undetermined abnormal birth outcome was classified as a major birth defect.
Results: Of 913 pregnancies, 399 (43.7%) were eligible with known outcomes. Maternal age was known in 216 cases, 45.4% were ≥35 years. Most frequent indications: cosmetic (35.5%), migraine/headache (30.2%), and movement disorders (12.0%). Dose information (242 cases): 32.2% <50U, 11.2% 50U to <100U, 40.0% 100U to <200U, and 16.5% ≥200U. 196 prospective cases (198 fetuses) – 152 (76.8%) live births, 45 (22.7%) abortions (32 spontaneous, 13 elective), 1 (0.5%) unknown birth type. 148 (97.4%) normal live births, 4 live births with abnormal outcomes, and 1 unknown with abnormal outcome (undetermined abnormality/possibly hole in heart). Among 5 abnormal birth outcomes (1 unknown): 2 major birth defects (1 live and 1 unknown), 2 minor fetal malformations (2 live), and 1 birth complication (1 live). Prevalence rates: 3.3% (5/153, 95% CI: 1.4-7.4%) for overall fetal defects (1 unknown) and 1.3% (2/153, 95% CI: 0.3-4.6%) for major fetal defects (1 unknown; 2-4% in general population).
Conclusion: A 29-year retrospective analysis of safety in onabotulinumtoxinA-exposed mothers demonstrated that prevalence rates of abnormal birth outcomes were within/below those reported in the general population, with no new safety signals identified.
To cite this abstract in AMA style:
M. Brin, A. Adams, L. Parker, A. Ukah, L. Radulian, L. Yedigarova, I. Yushmanova. Pregnancy Outcomes Following Exposure to OnabotulinumtoxinA Update – 29 Years of Safety Observation [abstract]. Mov Disord. 2020; 35 (suppl 1). https://www.mdsabstracts.org/abstract/pregnancy-outcomes-following-exposure-to-onabotulinumtoxina-update-29-years-of-safety-observation/. Accessed June 15, 2025.« Back to MDS Virtual Congress 2020
MDS Abstracts - https://www.mdsabstracts.org/abstract/pregnancy-outcomes-following-exposure-to-onabotulinumtoxina-update-29-years-of-safety-observation/