New York City's Mayor Michael Bloomberg has a new cause.

After proposing a ban on large soft drinks, he is pushing hospitals to keep baby formula locked up on maternity wards, so more new mothers will breast-feed, Fox News reported.

Bloomberg defended his voluntary “Latch On, New York” campaign, which starts on September 3.

According to WNYC, about 27 of the city's 40 hospitals have joined and "will begin taking a number of steps to encourage moms to nurse their newborns."

The New York-based public radio station said the hospitals will store the baby formula under "lock-and-key, like other medications" so nurses won't give out the formula so readily.

The hospitals have also agreed to give up "swag bags" to new mom's with formula related gifts.

Women who can’t do it, or don’t have the time to do it — you go for the formula,” Bloomberg said. “But I think most public health officials want to encourage women to breast-feed for the first couple weeks, because the outcomes are better.”

Many organizations including the Centers for Disease Control and Prevention and the World Health Organization encourage nursing over bottle-feeding but critics say the mayor is intruding on people's personal lives, WNYC reported.

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