Winning a backup day care benefit could theoretically help women move up in a company where only one woman is on an influential senior management team that reports directly to Bezos. (Photo: Shutterstock)

Amazon has long resisted pleas to provide a backup day care benefit for employees, even though other tech companies have offered the perk for years. Now a group comprising hundreds of working moms is waging a campaign to persuade founder and Chief Executive Officer Jeff Bezos that providing help for parents dealing with flu outbreaks, school closures and other emergencies is not simply humane but good for the company, too.

The group has been collecting anecdotal evidence to show how a lack of day care support can derail the careers of talented women who otherwise might be promoted to more senior jobs, according to an email reviewed by Bloomberg. Among the accounts: an Amazon.com Inc. manager tired of seeing colleagues quit because they can't find childcare in one of the country's fastest-growing cities and a recruiter frustrated when top talent leaves for companies that offer working parents more support.

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