Officers rushed to an emergency call at the Beechwood Drive home shortly before 7 p.m. Monday and found the woman conducting CPR, responders said.
The officers took over the life-saving measure for about 20 minutes, they said.
Paramus EMS -- escorted by police -- then took the infant to the Valley Hospital in Ridgewood, where a pulse was restored, Deputy Paramus Police Chief Robert Guidetti said.
The baby was later transferred to Mt. Sinai Hospital in New York City in critical condition, he said.
Paramus police and the Bergen County Prosecutor's Office were investigating along with state child welfare authorities.
"At this time nothing appears suspicious," the deputy chief said.
Reports of children in drowning North Jersey at this early point in the summer have become more than alarming. A 7-year-old Newark girl drowned over the weekend in a backyard Teaneck pool that its owners rent out for parties, authorities said.
SEE: 7-Year-Old City Girl Who Drowned In Rented Teaneck Backyard Pool Was Reported Missing
More children ages 1–4 die from drowning than any other cause of death except birth defects, according to the Centers for Disease Control.
For children ages 1–14, drowning is the second leading cause of unintentional injury death after motor vehicle crashes, the CDC says.
According to Mount Sinai, it "may be possible to revive a drowning person, even after a long period under water -- especially if the person is young and was in [extremely] cold water."
The baby in Paramus was in the water for a considerable amount of time, possibly 15 minutes or longer, responders said.
Still, "there are miracles," one said.
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