Early-pregnancy spontaneous abortion was almost twice as common among women who used benzodiazepines, according to 17 years’ worth of data from the Quebec Pregnancy Cohort, which prospectively collects data on all pregnancies of women covered by the Quebec Public Prescription Drug Insurance Plan.
The findings suggest the need for caution before prescribing benzodiazepines to treat insomnia and mood or anxiety disorders in early pregnancy. “Alternative nonpharmacologic treatments exist and are recommended, but if benzodiazepines are needed, they should be prescribed for short durations,” wrote Odile Sheehy, MSc, of the Research Center at Centre Hospitalier Universitaire Sainte-Justine, Montreal, and colleagues, in a study published in.
The researchers evaluated data from 27,149 study-eligible women who had a spontaneous abortion after 6 weeks’ gestation and before 20 weeks’ gestation between Jan. 1, 1998, and Dec. 31, 2015. Among filled prescriptions, at least one benzodiazepine was used by 375 (1.4%) of the women. These women were matched with five randomly selected control pregnancies per case. The data were adjusted for diagnoses of mood and anxiety disorders and insomnia as well as for several documented proxies of these diseases, such as concomitant exposure to antidepressants or antipsychotics, visits to a psychiatrist, comorbidities, and hospitalizations.
The investigators found an adjusted odds ratio (aOR) of 1.85 (95% confidence interval, 1.61-2.12) for benzodiazepine use. The odds of spontaneous abortion was increased with use of all types of benzodiazepines evaluated in the study, with aORs as low as 1.13 and as high as 3.43, as well as similar aORs between long-acting and short-acting benzodiazepines (1.81 vs. 1.73, respectively).
While the information is accurate regarding filled prescriptions, the findings might not apply to women with private drug insurance as the study included only women in a prescription drug program, the researchers said. They noted, however, that pregnant women receiving medication insurance from Quebec’s public system have characteristics and comorbidities similar to those of women who are covered by private medication insurance.
One author reported being a consultant for plaintiffs in litigations involving antidepressants and birth defects. No other disclosures were reported.
SOURCE: Sheehy O et al. JAMA Psychiatry. 2019 May 15. .