Dental Cleaning, Community Water Fluoridation and Preterm Birth, Massachusetts: 2009-2016.

Objectives Data on the potential effect of dental cleaning and community water fluoridation (CWF) on pregnancy outcomes are scarce. While numerous studies confirm the cost-effectiveness of fluoride in preventing dental caries, the benefit of CWF during pregnancy has not been well established. Methods This cross-sectional study used data from 2009 to 2016 Massachusetts Pregnancy Risk Assessment Monitoring System and restricted to singleton live births (n = 9234, weighted response rate = 64.3%). Our exposures were: (1) dental cleaning alone during pregnancy; (2) CWF alone; and (3) dental cleaning and CWF combined (DC-CWF). Women without dental cleaning during pregnancy and CWF comprised our reference group. The outcome was preterm birth, (birth < 37 weeks gestation). This study used multivariate logistic regression modeling, controlling for maternal sociodemographic characteristics, previous medical risk and behavioral factors, and calculated adjusted risk ratios (aRRs) and 95% confidence intervals (CIs). Results During 2009-2016, the prevalence of preterm birth among women with a singleton live birth was 8.5% in Massachusetts. Overall, 58.7% of women had dental cleaning during pregnancy, and 63.6% lived in CWF. After adjusting for potential confounders, the associations between dental cleaning alone and preterm birth (aRR = 0.74 [95% CI 0.55-0.98]), and DC-CWF and preterm birth (aRR = 0.74 [95% CI 0.57-0.95]) were significant, while the association between CWF alone and preterm birth was not significant (aRR = 0.81 [95% CI 0.63-1.05]), compared to women without dental cleaning and CWF. Conclusions for Practice This study shows that the prevalence of preterm birth was lower among women with DC only and DC-CWF.