“Only two of my kids were born from cases in which I handed off sperm to the mother in a public restroom. One was at the Hampton Inn hotel lobby bathroom in Queens and the other was in the bathroom in the family court in downtown Brooklyn.
“And for one of my children, I mailed the sperm,” he said.
He was recently in Israel to give sperm to an Israeli woman who had paid him to fly to the country to provide her with five specimens.
Mr Nagel, who has a further seven children on the way, had his sperm frozen at a Ramat Hasharon cryobank.
He spent his time in Israel visiting his brother, who lives in a West Bank settlement and also planned to see an eight-year-old son he fathered.
The 41-year-old does not charge women for his sperm, but insists they pay for him to travel to the place where he is to make the donation.
He has been sued for child support by five women and half of his $100,000 annual salary is believed to go toward child support payments.
Mr Nagel, who says he is aware of each and every one of his children and is in some sort of contact with their mothers, never asks women to put anything in writing. He just asks them not to sue him for child support, he says.
He said: “Two or three mothers asked me to sign something, but I didn’t bother to keep a copy. I didn’t think it was enforceable anyway.”