Two women were arrested Monday after, police say, they knocked down a pregnant woman, kicked and robbed her in the stairwell of a Bronx building.

Tiffany Nurse, 27, and Serenity Dunham, 18, knocked the 19-year-old victim down as she was walking down the staircase of the building on St. Ann’s Avenue and East 159th Street in Woodstock at about 2:15 p.m. on Thursday, Feb. 1, police said.

Nurse, of Morrisania, and Dunham, of West Farms, then repeatedly kicked the woman, took her cellphone and left her at the bottom of the stairs.

The victim, who told police she knew Nurse only by her first name, was taken to NYC Health + Hospitals/Lincoln and treated for bruising and swelling to her face.

The woman’s unborn child was not injured, police said.

Nurse and Dunham were charged with robbery and gang assault, the NYPD said.