U.S. District Judge Naomi Reice Buchwald on Thursday refused to issue a preliminary injunction against the change to the city's health code, which some members of the city's Orthodox Jewish communities called an unwarranted government intrusion on religious freedom.

In September, the New York City Board of Health voted to require mohels, who perform circumcisions, to obtain advance consent that tells parents about the risk of a potentially fatal herpes infection linked to the ritual of metzitzah b'peh, or MBP, involving direct oral suction of the penis.

Enforcement of the regulation was put on hold until Buchwald could rule on the request by the Central Rabbinical Congress of the USA and Canada, the International Bris Association and some rabbis for a preliminary injunction.

In court papers filed in October, they said the regulation improperly singled out an exclusively religious ritual, and violated the free speech and free exercise protections within the First Amendment of the U.S. Constitution.

But in a 93-page decision, Buchwald refused to halt enforcement of the regulation, and said the plaintiffs' claims were likely to be found without merit.

"There is ample medical evidence that direct oral suction places infants at a serious risk of herpes infection, as well as evidence that parents are sometimes unaware in advance of a circumcision that MBP will occur, and the regulation plainly addresses these legitimate societal concerns," Buchwald wrote.

"As enacted, the regulation does no more than ensure that parents can make an informed decision" whether to consent, she added.

Shay Dvoretzky, a partner at Jones Day representing the plaintiffs, was not immediately available for comment.

The city welcomed the decision. "Informing parents about the grave risks associated with this procedure is critical to safeguarding infants' health," Michelle Goldberg-Cahn, a senior lawyer for the city, said in a statement.

New York City said it plans to begin enforcing the consent requirement even if litigation continues.

City health officials on Thursday said at least 11 infant boys have in the last several years contracted a potentially fatal form of herpes following circumcision with direct oral suction, and that two of the boys died.

Opponents of the regulation have said the health department had not proven a higher incidence of neonatal herpes among boys who had received direct oral suction.

The case is Central Rabbinical Congress of the USA and Canada et al v. New York City Department of Health & Mental Hygiene et al, U.S. District Court, Southern District of New York, No. 12-07590.

(Reporting by Jonathan Stempel in New York; Editing by Lisa Shumaker)

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