After the deaths of two infants, a highly controversial Jewish circumcision practice in which the blood of a baby’s cut penis is sucked by a religious leader has been condemned .

The ‘metzitzah b’peh’–performed by ultra Orthodox Jews–is a practice in which an eight-day old baby is given a traditional circumcision, followed by the ‘mohel’ then placing his mouth around the wound and sucking up the blood.

The practice, while intended to prevent infection, has sparked controversy after the death of two infants and the contraction of herpes in at least 11 others between November 2000 and December 2011.

Heath chiefs in New York are now pushing for regulation forcing anybody wishing to have the procedure carried out on their babies to sign a consent waiver.

But some Orthodox Jews have complained about the measures claiming that they infringe on their ‘religious freedom’.

Professor of Talmudic Law and Bioethics at Yeshiva University Rabbi Moshe Tendler told KTLA that the practice was ‘primitive nonsense’.

‘The ritual has nothing to do with religion. It’s only their customs. But they’ve managed to convince the city that it’s a violation of their religious freedoms,’ he added.

Circumcision rituals originate from Scriptures, in which God tells Abraham that all men must be circumcised eight days after they are born.

Primitive Jews believed that blood was the ‘life-giving element’ and thought sucking it from the baby’s penis prevented infection.

But medical advances over the last hundred years have made clear that this practice increases the risk of infection. It is practiced widely in Israel and among Hasidic Jews.

After a death in Brooklyn last September, the city’s health department launched an investigation. A criminal investigation is still ongoing.

There was also an earlier death in November 2004, when a twin caught herpes after undergoing the procedure. The other survived.

Almost 20,500 baby boys had the procedure carried out in New York in June this year.

According to the findings of the investigation, infants who were circumcise with suction between April 2006 and December 2012 had a risk of catching neonatal herpes (HSV-1) infection of 24.4 per 100,000 cases.

New York City Health Commissioner Dr. Thomas Farley said in a statement: ‘There is no safe way to perform oral suction on any open wound in a newborn.

‘Parents considering ritual circumcision need to know that circumcision should only be performed under sterile conditions, like any other procedures that create open cuts, whether by mohelim or medical professionals.’

Jeffrey Mazlin, a certified mohel and physician in New York who regularly practices circumcision procedures, said Orthodox Jews look view the religion as ‘more important than individuals’.

‘Because blood is the life-giving element, they believe that it’s supposed to be part of the whole procedure,’ he said, adding that there were ‘no known medical benefits’.

Despite common knowledge that placing a penis–especially one with an open wound–in the oral cavity can spread disease, infectious diseases specialist Dr. Daniel S. Berman defended the practice in a paper published in the Jewish journal Dialogue. He claimed there is no evidence that the ‘metzitzah b’peh’ procedures caused the infant deaths.

Dr Berman accused New York government chiefs of ‘racial bias’.

Elite.