NigeriaDrug Delivery SystemsDelivery, ObstetricPregnancyHospitals, TeachingDrug CarriersCesarean SectionDelivery of Health CareInfant, NewbornGene Transfer TechniquesNanoparticlesPrevalenceCross-Sectional StudiesMedicine, African TraditionalHealth Knowledge, Attitudes, PracticeObstetric Labor ComplicationsMalariaGenetic TherapyPoliovirus VaccinesRural PopulationGenetic VectorsQuestionnairesPregnancy OutcomeMaternal MortalityOnchocerciasisPrenatal CarePoliomyelitisRetrospective Studies