Auspicious birth dates among Chinese in California

• Number 8 is considered lucky in Chinese culture.
• In California, “too many” births to Chinese occurring on the 8th, 18th, and 28th of month.
• The increase is driven by male births delivered by cesarean section.
• There is no corresponding increase on the 8th, 18th, and 28th of month for White births.
• Chinese in California may also avoid delivering on the 4th, 14th, and 24th of month.

The number eight is considered lucky in Chinese culture, e.g. the Beijing Olympics began at 8:08 pm on 8/8/2008. Given the potential for discretion in selecting particular dates of labor induction or scheduled Cesarean section (C-section), we consider whether Chinese-American births in California occur disproportionately on the 8th, 18th, or 28th day of the month. We find 2.3% “too many” Chinese births on these auspicious birth dates, whereas Whites show no corresponding increase. The increase in Chinese births is driven by higher parity C-sections: the number of repeat C-sections is 6% “too high” on auspicious birth dates. Sons born to Chinese parents account for the entire increase; daughter deliveries do not seem to be timed to achieve “lucky” birth dates. We also find avoidance of repeat C-section deliveries on the 4th, 14th, and 24th of the month, considered unlucky in Chinese culture. Finally, we replicate earlier work finding that Friday the 13th delivery dates are avoided and document a particularly large decrease among Chinese. For Whites and Chinese in California, mothers with higher levels of education are particularly likely to avoid delivering on the 13th.