State health commissioners announced on Tuesday that letters highlighting the importance of breastfeeding were being sent to hospitals, reminding them of regulations limiting unnecessary formula feedings for breastfed newborns.

The state initiative coincides with Bloomberg's call for hospitals to lock away their baby formula and have nurses encourage new mothers to breastfeed.

Under the mayor's plan, slated to start Sept. 3, the city will keep a record of the number of bottles that hospitals stock and use. Formula would be signed out like medication.

The pro-breastfeeding campaign has drawn the ire of some women who argue it stigmatised infant formula and interferes with a mother's choice of what to feed her child.

A number of the city's other health initiatives -- including cracking down on large-sized sodas and banning smoking in public places -- have attracted similar criticism from those who accuse the mayor of creating a "nanny" state.

"I breastfed both of my kids and it took me a good three weeks before I figured it out," said Rene Syler, who wrote about the issue on her website Goodenoughmother.com. "I can't imagine what it must be like to be in the hospital with someone sort of standing over your shoulder and lecturing you every time you ask for a bottle to feed your crying baby."

Under current regulations, hospitals are only allowed to provide formula to infants who have an indicated medical reason and a doctor's order for the supplemental feedings, the state health department said in a statement.

Still, only 39.7 percent of newborn infants in New York are exclusively breastfed -- well below the federal government goal of 70 percent, the state health department said. Roughly half of breastfed infants received supplemental formula in the hospital.

"We recognize that there are women that won't be able to breastfeed or chose to not breastfeed for a variety of reasons and that is a choice they should be able to make," said Dr. Barbara Wallace, the state health department's director of chronic disease prevention.

The state health department said the benefits of breastfeeding included fewer episodes of acute respiratory illnesses, inner-ear infections and gastroenteritis.

Mothers who do not breastfeed are at increased risk for postpartum bleeding and anemia, and have higher rates of breast cancer later in life, the health department statement said.