Prevalence and predictors of anti-infective use during pregnancy

(1) Measure the prevalence and trends of anti-infective drug use before, during, and after pregnancy; (2) to list the doses, classes, types, and indications for anti-infective use during pregnancy; and (3) to identify predictors associated with anti-infective drug use during pregnancy.

Retrospective cohort study within the Quebec Pregnancy Registry, which was created by the linkage of three administrative databases: RAMQ, Méd-Echo, and ISQ. Women were eligible if they were (1) continuously insured by the RAMQ drug plan for at least 12 months before the first day of gestation, during pregnancy and 12 months after the end of the pregnancy and (2) if they gave birth to a live born between January 1998 and December 2003. Ninety-seven thousand six hundred and eighty pregnant women met the eligibility criteria. Data were collected for systemic agents. Logistic regression models were used to quantify predictors of use.

Prevalence of anti-infective use during pregnancy was 24.5%. Penicillins use increased compared to other classes. The most frequently diagnosed infections were respiratory and urinary tract infections. Predictors associated with use at the beginning of gestation were having > or =2 different prescribers [OR = 3.83 (95% confidence interval 95%CI: 3.3-4.3)], diagnosis of urinary [OR = 1.50 (95%CI: 1.3-1.8)], and respiratory tract infection [OR = 1.40 (95%CI: 1.2-1.6)] in the year before pregnancy. Visits to an obstetrician/gynecologist were protective for use [OR = 0.81 (95%CI: 0.67-0.97)].

Anti-infective use during pregnancy is prevalent. The oldest and safest agents are preferred.