A Manhattan federal judge refused to block a New York City regulation requiring people who perform circumcisions and use their mouths to draw away blood from the wound on a baby’s penis to first obtain written consent from the parents.

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.

Akiva Shapiro, who argued on behalf of a group of medical organizations that support the measure, wrote in an email to the Forward that the court was correct in protecting children from potential health risks.

“The court correctly found it ‘incontrovertible’ that infectious diseases can be, and have been, transmitted through direct oral suction during circumcision,” he wrote. The judge also said the regulation, “is narrowly tailored to protect the fundamental right of parents to make informed decisions about, and control, the medical care and religious upbringing of their children,” he added.

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.

Hank Sheinkopf, a spokesperson for the plaintiffs, said in a statement, that they were “disappointed” by the decision but looked forward “to ultimately vindicating our constitutional rights of freedom of religion and speech,” and that they “continue to believe that the city’s regulations are a misguided and unnecessary intrusion into a sacred religious ritual.”

In court papers filed in October, the plaintiffs 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.

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.