Maternal Betahistine Exposure and Pregnancy Outcomes: A Retrospective Cohort Study

Background In the general population, betahistine has a good safety profile. However, there is insufficient data on betahistine use during pregnancy; safety and teratogenic risks are yet to be evaluated. The study aimed to review pregnancy outcomes in women who were exposed to betahistine during their pregnancies and identify the rate and pattern of major malformation. Material and methods A descriptive retrospective cohort study was conducted. Pregnant women who were prescribed betahistine from Hamad Medical Corporation hospitals between 1st-April-2020 and 31st-March-2022 and had their delivery or abortion at the Women's Wellness and Research Center, Qatar, were included. Patients were followed up until the occurrence of the study outcomes (delivery or abortion), with an additional two months of follow-up for the baby if data were available. Ethical approval was obtained from the Medical Research Center (MRC-01-23-223). Results Forty pregnant women were included, with 42 baby outcomes (including two sets of twins). Betahistine daily dose ranged between 16 mg and 48 mg, with 75% of patients receiving the higher dose of 48 mg. The majority of patients received betahistine during the first trimester (90%) and for a short duration of ≤ 14 days (80%). Six pregnancies ended with spontaneous miscarriage (14.3%), and 34 pregnancies resulted in 36 live babies (85.7%). Four babies (11.1%) were preterm (delivered before 37 weeks of gestation), and four babies had a weight < 2500 g at birth (11.1%). Thirty-one babies had normal outcomes (86.1%), five babies had minor malformations (13.9%), and none had major malformations. These minor malformations were mild pyloric stenosis, bilateral positional talipes, displaced ear, umbilical hernia, hydrocele, tongue tie, and bilateral talipes calcaneus. Conclusions The current study does not suggest an increased rate of major congenital malformations following in-utero betahistine exposure. However, the small sample size and retrospective nature of the data warrant caution in result interpretation and do not confirm its safety for use in pregnant women. Avoidance of unnecessary medication during pregnancy is advisable whenever possible.