“I knew that I wanted to raise my child Jewish and in a Jewish home. And yet I’m also a feminist and activist, and believe very strongly in the right to your own body,” she said.

She decided not to circumcise, a choice she said her parents eventually accepted. Instead she had a “gentle bris” ceremony with alternative ritual objects: a pomegranate, a gold kiddush cup, and a large ceramic bowl filled with water to wash the baby’s feet, an ancient act of welcoming the stranger. Ms. Edell cut the pomegranate, a totem of fertility with its plentiful seeds, while her mother held her son.

There’s no reliable data on the percentage of American Jewish boys who are circumcised each year. But there are some indicators to suggest why circumcision may be subject to increasing debate: A Pew survey of American Jews in 2013 revealed a significant rise in secular Jews who are marrying outside the faith, and roughly a third of intermarried Jews who are raising children say they aren’t raising them Jewish. Only 19 percent of American Jews said that observing Jewish law was an essential part of what being Jewish means. (In contrast, 42 percent said “having a good sense of humor” was essential.)

“They’re inadvertent trailblazers. They’re certainly pushing the boundary of who can be a Jew,” said Rabbi Peter Schweitzer of the City Congregation for Humanistic Judaism in Manhattan. Rabbi Schweitzer does alternative ceremonies for people who choose not circumcise.

Of course, there haven’t been changes across the board. For Orthodox families, who constitute about 10 percent of the American Jewish population, the traditional bris remains immutable.

“You have a boy, you have a bris,” said Cantor Philip Sherman, an Orthodox mohel who estimates he’s performed more than 21,000 bris ceremonies. Those who choose to opt out “don’t have a connection to their Jewish heritage.”

“They don’t know how important and significant this is,” he said. “If they did, they wouldn’t take the position they’re taking.”