N.Y. Real Prop. Acts. Law § 237

§ 237. Discrimination in leases with respect to bearing of children.\nAny person, firm or corporation owning or having in charge any apartment\nhouse, tenement house or other building or mobile home park used for\ndwelling purposes who shall, in any lease of any or part of any such\nbuilding or mobile home park, have a clause therein providing that\nduring the term thereof the tenants shall remain childless or shall not\nbear children, shall be guilty of a violation.\n