title: Child spacing: as old as mankind.
authors.forename: D B
authors.initials: DB
authors.lastname: Jelliffe
authors.forename: P E
authors.initials: PE
authors.lastname: Jelliffee
mesh_terms: D001721:Birth Intervals; D001723:Birth Rate; D003710:Demography; D005193:Family Planning Services; D005298:Fertility; D007774:Lactation; D011153:Population; D011157:Population Dynamics; D011388:Prolactin
chemical_list: D011388:Prolactin