Maternal veterinary occupation and adverse birth outcomes in Washington State, 1992-2014: a population-based retrospective cohort study.

Abstract

Women in veterinary occupations are routinely exposed to potential reproductive hazards, yet research into their birth outcomes is limited. We conducted a population-based retrospective cohort study of the association between maternal veterinary occupation and adverse birth outcomes. Using Washington State birth certificate, fetal death certificate and hospital discharge data from 1992 to 2014, we compared birth outcomes of mothers in veterinary professions (n=2662) with those in mothers in dental professions (n=10 653) and other employed mothers (n=8082). Relative risks (RRs) and 95% CIs were estimated using log binomial regression. Outcomes studied were premature birth (<37 weeks), small for gestational age (SGA), malformations and fetal death (death at ≥20 weeks gestation). Subgroup analyses evaluated risk of these outcomes among veterinarians and veterinary support staff separately. While no statistically significant associations were found, we noted a trend for SGA births in all veterinary mothers compared with dental mothers (RR=1.16, 95% CI 0.99 to 1.36) and in veterinarians compared with other employed mothers (RR=1.37, 95% CI 0.96 to 1.96). Positive but non-significant association was found for malformations among children of veterinary support staff. These results support the need for further study of the association between veterinary occupation and adverse birth outcomes.