Most databases have search filters for sex, but to using subject headings allows for more specificity when researching maternal health issues:
("Maternal Nutritional Physiological Phenomena"[Mesh])
("Maternal Health Services"[Mesh])
("Alaskan Natives"[Mesh])
("American Native Continental Ancestry Group"[Mesh])
("Ethnopharmacology"[Mesh])
("Health Services, Indigenous"[Mesh])
("Indians, North American"[Mesh])
("Inuits"[Mesh])
("United States Indian Health Service
(MH "Maternal Nutritional Physiology")
(MH "Maternal Health Services")
(MH "Maternal Age 35 and Over")
(MH "Maternal Age 14 and Under")
(MH "Native Americans") [NOTE: "For native peoples of the United States and non-Arctic Alaska regions"]
(MH "Medicine, Native American")
(MH "Inuit") [NOTE: "Group of culturally similar indigenous peoples of Arctic and near-Arctic Canada, Alaska, and Greenland."
(MH "Health Services, Indigenous")
(MH "Eskimos") [Note: "For genetic and physiological as well as cultural and social discussion of Eskimos."