Objective:

To investigate the association between community water fluoridation and adverse birth outcomes, including birth weight.

Key Findings:

• No statistically significant changes in birth weight associated with community water fluoridation.
• The main difference-in-differences estimate showed a change of –0.53 g, not clinically meaningful.
• Secondary outcomes, including rates of low birth weight, gestational length, and prematurity, showed no association with fluoridation.

Interpretation:

The study provides reassurance regarding the safety of community water fluoridation during pregnancy, countering concerns raised by previous observational studies.

Limitations:

• The study is limited to the data available from the specified time period and geographic regions.
• Potential exposure misclassification was addressed but may still exist.

Conclusion:

Community water fluoridation is not associated with adverse birth outcomes, contributing to the ongoing evaluation of its safety during pregnancy.