As word spread, two other institutions approached New York Hospital regarding joining the new medical center complex: The Society of the Lying-In Hospital of the City of New York, and Manhattan Maternity and Dispensary. Both institutions had financial troubles and wished to be part of this brand new medical facility.
John Pierpont Morgan, Jr., a benefactor and chair of the Lying-In Hospital Board of Directors, approached New York Hospital regarding absorbing the Lying-In Hospital. New York Hospital agreed to the affiliation if the Lying-In Hospital would pay $6,000,000. John Pierpont Morgan, Jr. donated $2,000,000 and received $1,000,000 each from George Baker, Sr. and Jr., and $2,000,000 from the Laura Spelman Rockefeller Foundation.
The affiliation agreement between The Society of the Lying-In Hospital of the City of New York and The Society of the New York Hospital was signed on June 19, 1928. Under the agreement, the Lying-In Hospital became the Department of Obstetrics & Gynecology (Women’s Clinic) at the new medical center.
Since New York Hospital had already made an agreement with the Lying-In Hospital to become the medical center’s Women’s Clinic, the Board of Directors of Manhattan Maternity and Dispensary signed an affiliation agreement on March 19, 1929 to become the medical center’s Department of Pediatrics (Children’s Clinic).
Later on March 15, 1947, The Lying-In Hospital of the City of New York, Manhattan Maternity and Dispensary and New York Nursery and Child’s Hospital (which had joined the medical center in 1934) completed a formal legal merger with The Society of the New York Hospital.